Ecology and biodiversity of agriculturally important rice field arthropods

ECOLOGY AND BIODIVERSITY OF AGRICULTURALLY
IMPORTANT RICE FIELD ARTHROPODS
Thesis
Submitted to the
University of Madras
in partial fulfillment of the requirements for the degree of
Doctor of Philosophy
by
J. Diraviam
Post Graduate & Research Department of Zoology
Loyola College (Autonomous)
Chennai 600 034
June 2005

Rice cultivation
• Rice is the staple food for over 65% of the
Indian population, grown in the country in an
area of about 45 million hectares.
• In Tamil Nadu state, rice is cultivated under
irrigated condition to a large extent and under
semi-dry & dry conditions to a limited extent.semi-dry & dry conditions to a limited extent.
• North-eastern zone of Tamil Nadu has a large
area under rice in three overlapping seasons
due to its favourable climatic conditions.
• The high humidity prevailing during the
monsoon season triggers the build-up of
important insect pests and diseases.

Rice cultivation
Indiscriminate Application of Insecticides
Resulted in the reduction of biodiversity of
natural enemies,
Development of pesticide-induced resistance,
and
Outbreak of secondary pests (Garg et al.,
2004).
Believed to be the oldest form of intensive
agriculture (Fernando, 1977)
Dates back to nearly 9000 years ago
It is thought to have originated in northeast
Thailand (Bray, 1986)

Biological Diversity
It is the full range of variety &
variability within and among living
organisms, their associations, and
habitat-oriented ecological complexes.
The term encompasses:The term encompasses:
ecosystem,
species, and
Landscape, as well as
intra-specific (genetic) levels of
diversity
(Fielder and Jain, 1992)

Biological Diversity
NATURAL RESOURCES: Soil, Water,
Biodiversity, Atmosphere, etc.
BIODIVERSITY of Plants, Animals,
Microbes:
Enormous direct economic benefit to
humankind
An array of indirect essential services
thro’ natural ecosystems, and
Plays a prominent role in modulating
ecosystem function & stability (Singh,
2002)

ARTHROPODS
The most diverse & numerous of all
living organisms,
Form the most importantForm the most important
components of diverse ecosystems,
as well as
The major players in the functioning
of those ecosystems (Wilson, 1987;
Miller, 1993; Kim, 1993)

Rice Ecosystem
Considered as man-modified
environment,
An integrated water
dependent system, which
includes:includes:
rice plant,
animals and plants,
humans,
and crops other than rice
(Kiritani, 1979).

Earlier Studies
Several workers conducted
faunistic surveys of the
arthropod taxa in rice
ecosystemsecosystems
Others developed inventories
for rice arthropods based on
published information

Newly kindled interest on the
study of arthropod biodiversity
Based on the rice ecosystem, Kiritani
(2000) further proposed a new
concept called:concept called:
‘Integrated Biodiversity Management’
(IBM) under which
Integrated Pest Management (IPM) and
conservation ecology are integrated.

Role played by the biotic &
abiotic factors on arthropod
diversity
Rice field undergoes several
disturbances due to agronomic
practices such as:practices such as:
tillage, irrigation, fertilization,
pesticide application, &
weeding, which influence the
biodiversity (McLaughlin and Mineau,
1995; Bambaradeniya, 2003).

Role played by the biotic & abiotic
factors on arthropod diversity
Weather factors such as
temperature,
relative humidity and
rainfallrainfall
also affect the population dynamics &
abundance of arthropods (Dyck et al.,
1979; Dale, 1994; Singh et al., 2000), which in
turn affect the biodiversity (Way and
Heong, 1994).

Biotic Influences
Predation, parasitism & disease
incidence also affect the arthropod
abundance in rice ecosystem (Ooi and
Shepard, 1994; Rombach et al., 1994;
Narayanasamy, 1998,2001).Narayanasamy, 1998,2001).
There is an increased awakening
regarding the need for conservation
of arthropod fauna in different
ecosystems (Kim, 1993; Ghosh, 1996;
Kiritani, 2000).

Study on prey-predator relationships
& the influence of agronomic factors
• Gains importance while considering
the conservation perspective (Settle et
al., 1996; Drechsler and Settele, 2001; Sigsgaard et
al., 2001a,b).
• Application of organic matter forms• Application of organic matter forms
the key factor in the conservation of
generalist predators by enhancing
the population of the neutrals that
serve as alternate prey (Settle et al., 1996).

Objectives
1. To study the species composition of
agriculturally important arthropods in
rice ecosystems,
2. To quantify the biodiversity in terms
of species diversity, richness andof species diversity, richness and
evenness using various indices,
3. To study the influence of agronomic
practices on the biodiversity,
4. To study the population dynamics of
important arthropods,

Objectives (contd.)
5. To study the effects of weather
factors on important arthropods,
6. To study the spatial distribution of
important arthropods,
7. To study the ecological succession7. To study the ecological succession
of important arthropods, and
8. To study the predator- prey
relationship among important
arthropods to promote integrated
rice insect pest management.

Biodiversity of arthropods in rice
ecosystem has received lot of
attention during the past one decade
(Way and Heong, 1994; Settle et al., 1996; Schoenly et al.,1998;
Kiritani, 2000; Bambaradeniya, 2003)
• This awakened interest is
largely due to the
occurrence of
largely due to the
occurrence of
wide range of insects,
arachnids and
other arthropods
that closely interact with
each other & help in the
stability of the ecosystem
(Cohen et al., 1994).

COMMUNITY TURNOVER OF TAXA (%TO)
• To estimate the succession rates of
fauna in an ecosystem.
• Schoenly et al. (1998): %TO increased
over the cropping season in the canopy
as well as the floodwater.as well as the floodwater.
• Maximum difference in %TO occurred
during canopy closure & the reason for
the increase in %TO was due to the
difference between the taxa observed in
the earlier & the later stages of the crop.

ARTHROPOD POPULATION
in Rice Ecosystem
> 350 species of
insects attack rice
crop in India
• Only five species are
considered as majorconsidered as major
pests
• Another four species
as minor pests
(Chelliah et al., 1989;
Gunathilagaraj and Kumar,
1997a).

Main Reasons for Pest Abundance
• Widespread planting of pest
susceptible modern varieties
• Closer planting
• Excessive dose of nitrogenous
fertilizer
• Indiscriminate application of
insecticides
• Rapid expansion of irrigation
systems, &
• Inadequate weed control (Kenmore
1980)

SPATIAL DISTRIBUTION
• Distribution patterns of many
arthropods,
within-plant &
between-plant,
are relatively unstudied for the paddyare relatively unstudied for the paddy
ecosystem (Heong et al., 1991).
As such, it is difficult to design a
comprehensive IPM without adequate
information on distribution statistics
& parameters.

Weediness in Rice Fields &
Arthropod Biodiversity
• Rank abundance values exhibited
that GLH & BPH were the dominant
species in weeded plots.species in weeded plots.
• Among the natural enemies,
damselfly, mirid bug, spiders,
bethylids, braconids & coccinellids
were dominant in unweeded plots.
Kandibane et al. (2003)

• STUDY SITES: Kancheepuram,
Tiruvallur, Vellore & Villupuram
districts in Tamil Nadu.
• Most studies confined to Kovur
village of Kancheepuram dt.,
where rice is raised in threewhere rice is raised in three
seasons:
• Navarai (January-April),
Sornavari (April - August) and
Samba (August - December).

STUDY SITES: Farmers’ rice fields:
KANCHEEPURAM dt. (6)
• Kovur, Vallam, Nanmangalam
• Malaiyambakkam, Girugambakkam,
Katrambakkam
TIRUVALLUR dt. (5)TIRUVALLUR dt. (5)
• Budur, Kavarapettai, Venkathur-
Kandigai, Nandimangalam,
Narasingapuram
VELLORE dt. (1): Senthamangalam
VILLUPURAM dt. (1): Jakkampettai

• STUDY SITES in Kovur: Not applied
with pesticides for over six years.
Observations in 5 seasons.
• SEMI-DRY: Vallam, Kancheepuram
dt. & WET: Budur in Tiruvallur dt.:dt. & WET: Budur in Tiruvallur dt.:
At least one season study was
made.
• Other locations (8 in 4 districts):
roving surveys (1 to 3 observations).

SPECIES COMPOSITION
• Surveys & collection of field
arthropods: hand collection, visual
observation, & net sweep collection;
Light Trapping
• Identification: All Arthropods were
grouped based on their taxonomicgrouped based on their taxonomic
order, & identified up to genera &
species levels, wherever possible.
• They were preserved as per
procedures given by Borror et al.
(1989).

Identification of Insects / Spiders
BY TAXONOMISTS AT:
UAS, Bangalore
Sacred Heart College, Kochi
University of Calicut
Annamalai University
PDBC, ICAR, Bangalore
IARI, New Delhi
Guru Nanak College, Chennai
St. Xavier’s College, Palayamkottai
Delhi University, Delhi, &
ZSI, Regional Station, Jodhpur.

BIODIVERSITY INDICES
• α or within-habitat diversity;
• β or between-habitat diversity
(Whittakar, 1972)
• Shannon-Weaver (1940) index• Shannon-Weaver (1940) index
of diversity (H’)
• Evenness Index (vide Ludwig and
Reynolds, 1988).
• Relative-abundance curves
(Krebs, 1985)

Richness Indices
Hill’s Number 0 (N0)
Margalef (1958) index (R1):
R1 = S – 1
ln(n)
Menhinick (1964) index (R2):
R2 = SR2 = S
√√√√n
Rarefraction method (Hurlbert, 1971)
s
E (Sn) = ΣΣΣΣ 1 - N - ni N
i=1 n n

Diversity Indices
• Simpson’s index (λλλλ): (1949)
s
λλλλ = ΣΣΣΣ pi2
i=1i=1
Shannon’s index (H’): (1949)
s
H’ = ΣΣΣΣ (pi ln pi)
i=1

Evenness Indices
E 1 = H’ = ln (N1) (Pielou, 1977)
ln(S) ln (N0)
E 2 = eH’ = N1 (Sheldon, 1969)
S N0
E 3 = eH’ - 1 = N1 – 1 (Heip, 1974)
S - 1 N0 - 1S - 1 N0 - 1
E 4 = 1/λλλλ = N2 (Hill, 1974)
eH’ N1
E 5 = (1/λλλλ) – 1 = N2 – 1
eH’ - 1 N1 -1 (Ludwig &
Reynolds, 1988)

β Biodiversity Indices:
Index of Similarity
Jaccard Index of Similarity:
Cj = j / (a + b – j)Cj = j / (a + b – j)
(Magurran 1988)
• Sorensen Index of Similarity:
Cs = 2 j / (a + b)
(Southwood, 1978)

INFLUENCE OF AGRONOMIC
PRACTICES ON THE BIODIVERSITY
Relative abundance (Krebs, 1985)::
No. of individuals of particular species x 100
Total numbers of individuals of all species
No. of individuals of particular species x 100
Total numbers of individuals of all species
Pest: Natural enemy ratio
Community turnover of taxa (Diamond,
1969):
% TO(t) = 100 x [(a + b) / (c + d – e)]

Impact of soil application of carbofuran
on the biodiversity of predatory fauna
Field experiments: Navarai 2002 season
IPM field: FYM 20 t/ha; No chemical
fertilizers & pesticides.
Farmers’ practice field: One soil appln.Farmers’ practice field: One soil appln.
of carbofuran 3G at 6 kg/ha, 30 DAT in
standing water.
# Weekly observations on pests &
predators from transplanting.
# Experimental plot: 50-cents; 5 micro-
plots of 1 cent each; 5 hills per plot;
Total 25 hills / treatment.

Effect of fertilizer & carbofuran on
predatory arthropod fauna
# Sornavari 2002 season; ADT 43
# IPM field: Interplanted with Sesbania
rostrata in rogue spacing; FYM 15 M.
T/ha; No pesticide.
# Farmer’s practice field: No S.
rostrata; FYM 5 M.T./ha; Water surfacerostrata; FYM 5 M.T./ha; Water surface
appln. of carbofuran 3G at 6 kg/ha on 65
DAS.
# Both fields applied with equal levels
of one basal and two top dressings with
N & K fertilizers.
# Weekly observations on pests &
predators on 25 hills.

Sesbania rostrata
interplanted in the
IPM rice field in Kovur
Stem nodules in
S. rostrata plants
in flowering stage

Effect of monocrotophos &
profenofos on predatory spiders
Navarai season 2003
Plot size 50 cents
Weekly observations on leaf
folder incidence & damage, &
spider population on 10 hills
folder incidence & damage, &
spider population on 10 hills
from 30 DAS
First spray with monocrotophos
at 120 ml/ha on 35th DAP.
Second round with profenofos
at 120 ml/ha on 45 DAP.

Impact of neem oil on the
biodiversity of arthropods
• IPM Field: One round of neem oil @
900 ml/ac
• 50 double sweep net samples• 50 double sweep net samples
• Specimens grouped into three
guilds, viz., pests, entomophages
and neutrals.

EFFECT OF WEATHER FACTORS ON
ARTHROPOD POPULATION
• Population in a 2000 sq. m. plot rice was
computed by taking weekly
observations on 25 hills
• Also during Sornavari 2003 season,
sweeping by sweep net was used.sweeping by sweep net was used.
• Correlation and regression analysis
• Different groups of spiders were
combined.
• Major pests & predators were kept
separately, whereas minor groups were
combined together.

WEATHER PARAMETERS
• Max. & min. temp., RH & RF
i. Weekly mean for temp. RH data, &
Ii. Weekly total rainfall
• Mean weather factors were used for
season-wise data as well as for allseason-wise data as well as for all
seasons’ data.
• Extreme weather factors recorded
during the preceding week.
• Pest incidence over 5 per 25 hills
were alone considered.

SPATIAL DISTRIBUTION
• Worked out using index of dispersion
((Ludwig & Reynolds, 1988)(Ludwig & Reynold
• Pests or predators, which occurred at
least five times in a season, were alone
considered.
• Spatial distribution was measured using
the Index of Dispersion (ID):
ID = s2
--------
x
Significance of ID
2 = ID (N-1)

STATISTICAL ANALYSIS
• Biodiversity indices observed in
different seasons and in IPM & non-
IPM fields were analyzed by ANOVA
(Snedecor & Cochran, 1967) using the(Snedecor & Cochran, 1967) using the
software ‘ANOVA Package for
Researchers’ (Version 7.01).
• Correlation and regression analysis
(Snedecor & Cochran, 1967) were done by
the computer software MS Excel.

SPECIES COMPOSITION OF DIFFERENT
AGRICULTURALLY IMPORTANT
ARTHROPODS
• 313 taxa of insects under 110
families & 15 orders
• 61 taxa of spiders under 16• 61 taxa of spiders under 16
families,
• 5 taxa of mites under 3 suborders
& 5 families
were observed in rice nurseries /
main fields in all locations.

INSECTA: HERBIVORES
• Orthoptera (grasshoppers),
• Hemiptera (black bug, orange bug),
• Homoptera (leaf hopper, planthopper,
whitefly),
• Thysanoptera (thrips),• Thysanoptera (thrips),
• Lepidoptera (leaf folder, stemborer,
cutworm, skipper),
• Coleoptera (flea beetles, hispa), and
• Diptera (gall fly).

• Orthoptera: Oxya nitidula, O. fuscovittata, Acrida
exaltata, Eyprepocnemis alacris, Truxalis indicus,
Atractomorpha crenulata, Ailopus thalassinus
tamulus
• Hemiptera: Scotinophara lurida, S. bispinosa,
Menida histrio, Leptocorisa oratorius, Eysarcoris
guttiger
HERBIVORES
guttiger
• Homoptera: Nephotettix virescens, Deltocephalus
dorsalis, Empoascanara indica, Sogatella
furcifera, Nilaparvata lugens, Hysteroneura
setariae, Rhopalosiphum nymphaeae, Bemisia
tabaci, Pyrilla perpusilla, Nisia nervosa

Thysanoptera: Haplothrips ganglbaueri,
Stenchaetothrips biformis, Podothrips
lucasseni, Anaphothrips sudanensis
• Lepidoptera: Cnaphalocrocis medinalis),
Pelopidas mathias, Scirpophaga incertulas,
Mythimna loreyi & M. separata, Spodoptera
HERBIVORES (CONTD.)
Mythimna loreyi & M. separata, Spodoptera
mauritia, Melanitis leda ismene & Psalis
pennatula, Amsacta lineola.
• Coleoptera: Chaetocnema concinnipennis,
Dicladispa armigera, Chaetocnema sp.,
Lema sp., & Monolepta signata
• Diptera: Orseolia oryzae

ENTOMOPHAGES: PREDATORS
• Odonata: Dragonfly & damselfly
• Hemiptera: Assassin bug, mirid bug,
anthocorid bug & water bug
• Coleoptera: Ground beetle, rove beetle &
ladybird beetle
• Dermaptera: Earwig• Dermaptera: Earwig
• Hymenoptera: Ant & wasp
• Orthoptera: Long-horned grasshopper,
cricket
• Diptera: predatory ephydrid fly
• Neuroptera: Ant-lion & owl fly
• Mantodea: preying mantis

• Odonata: Agriocnemis pygmaea,
Ischnura senegalensis, Pantala
flavescens & Diplacodes trivialis
• Hemiptera: Cyrtorhinus lividipennis,
Polididus armatissimus, Andrallus
spinidens, Proboscidocoris distanti,spinidens, Proboscidocoris distanti,
Geocoris sp., Nabis sp.
• Coleoptera: Ophionea indica,
Micraspis discolor, Paederus
fuscipes, Brumoides suturalis,
Scymnus (Neopullus) hoffmani

• Dermaptera: Euborellia sp.
• Hymenoptera: Ropalida marginata,
Camponotus rufoglaucus, C. sericeus,
C. paria, Monomorium floricola,
Monomorium sp., Myrmicaria brunnea
• Orthoptera: Conocephalus maculates,• Orthoptera: Conocephalus maculates,
Euconocephalus incertus
• Diptera: Ochthera sp.
• Neuroptera: Palparus carinatus

ENTOMOPHAGES: PARASITOIDS
• HYMENOPTERA: Braconids,
chalcidids, eulophids, elasmids,
ichneumonids, mymarids,ichneumonids, mymarids,
pteromalids, scelionids &
trichogrammatids
• DIPTERA: Pipunculids, Tachinids

• HYMENOPTERA:
Paraphylax sp. (Ichneumonidae),
Gonatoceros sp. (Mymaridae),
Trichomalopsis nigra (Pteromalidae),
Telenomus sp. (Scelionidae),
Trichogramma sp. (Trichogrammatidae),
Calliscelio sp., Holoteleia sp., Lepto-
teleia sp. & Psilanteris sp. (Scelionidae).teleia sp. & Psilanteris sp. (Scelionidae).
• DIPTERA:
Palexorista solennis, Peribaea orbata,
Pseudoperichaeta insidiosa,
Blepharella lateralis (Tachinidae) &
Tomosvaryella oryzaetora (Pipunculidae)

NEUTRALS
• Diptera (chironomids, sciomyzids,
chloropids & phorids)
• Coleoptera (bruchids, chrysomelids,
curculionids, hydrophilids &
tenebrionids)
• Hemiptera (lygaeids and plataspid)• Hemiptera (lygaeids and plataspid)
• Hymenoptera (bees & fig wasps)
• Lepidoptera (geometrids)
• Collembola (spring tails)
• Ephemeroptera (mayflies), &
• Psocoptera (psocids).

NEUTRALS
• DIPTERA: Sepedon sp. (Sciomyzidae)
• COLEOPTERA:
Apion sp., Nanophyes sp. (Apionidae),
Callosobruchus sp. (Bruchidae),
Cryptocephalus sp., Aphthona sp., Zygogramma
bicolorata, Phyllotreta chotanicabicolorata, Phyllotreta chotanica (Chrysomelidae),
Sibinia spp., Ceuthorrhynchus sp., Myllocerus
dentifer, Xanthochelus faunus (Curculionidae),
Aeloderma sp. (Elateridae),
Calandra sp. (Rhynchophoridae),
Gonocephalum sp. (Tenebrionidae)

NEUTRALS
• HEMIPTERA:
Nysius spp. (Lygaeidae),
Coptosoma sp. (Plataspididae),
Clavigralla sp. (Coreidae)
Micronecta sp. (Corixidae)Micronecta sp. (Corixidae)
Halys dentatus (Pentatomidae)
• LEPIDOPTERA:
Amata pasalis (Amatidae)
Grammodes geometrica, Spodoptera litura
(Noctuidae)

ARACHNIDA
• HERBIVORES: Acari: Oligonychus sp.
• PREDATORS: Araneae: 15 families; most
common were Araneidae, Lycosidae, Salticidae &
Tetragnathidae
Acari: Predatory mites: Amblyseius
longispinosus (Phytoseiidae), Lasioseius
Acari: Predatory mites: Amblyseius
longispinosus (Phytoseiidae), Lasioseius
parberlesei (Ascidae)
PARASITOIDS: Acari: An undet. sp.
(Trombididae)
NEUTRALS: Acari: An undet. sp. (Crypto-
stigmata)

• Biodiversity studies in India in
rice ecosystems by Premila et al.
(2003) & Singh et al. (2003).
• Biodiversity inventory of the• Biodiversity inventory of the
fauna associated with rice
agro-ecosystems in coastal
districts of Orissa by Behera et
al. (2003).

• Diversity of predatory beetles of
Karaikal region (Manisegaran et al., 2005);
• Spiders in Kerala & their seasonal
variation (Sebastian et al., 2005;
Sudhikumar et al., 2005) &
• Spiders in Gujarat (Kumar and
Shivakumar, 2005)
• Not many detailed studies are
available on the biodiversity of
important arthropods in Tamil Nadu.

SPECIES COMPOSITION
Li et al.
(2001):
China
The arthropods in paddy fields
included:
2 classes, 13 orders,
95 families, 192 genera &
261 species.
Bambara- Arthropods were the dominantBambara-
deniya et
al. (2004):
Sri Lanka
Arthropods were the dominant
group of:
Invertebrates comprising of
405 species, of which
55 species were rice pest
insects, &
>200 species were natural
enemies of pest insects.

ENTOMOPHAGES
ARTHROPOD NATURAL ENEMIES
OF RICE PEST INSECTS:
• PREDATORS: Spiders & insects
such as carabid beetles, aquatic &such as carabid beetles, aquatic &
terrestrial predatory bugs and
dragon flies
• PARASITOIDS: Hymenopteran
wasps & a few dipteran flies

Fungal infections
In grasshopper
(top) and(top) and
moth (bottom)

• Ooi and Shepard (1994): The
long histories of rice cultivation
in Asia have allowed stable
relationships to evolve between
rice insect pests & their natural
enemies.enemies.
• Insects as natural enemies in
paddy fields of Chongqing
region of China included:
• 7 orders, 27 families, 53 genera &
64 species (Li et al., 2001).

Anbalagan & Narayanasamy (1999):
Spider species diversity was found
to be directly related to the growth
stages of the rice plant.
Kandibane et al. (2003):
Arthropods exhibited greater
diversity during successional age
of crop.

New Records of Insects from rice
ecosystem during the study
Order Family Genus/species
Hemiptera Reduviidae Euagoras plagiatus (Burmeister)
Pygolampis unicolor Walker
Thysanoptera Thripidae Exothrips sp.
Hydatothrips sp.Hydatothrips sp.
Megalurothrips sp.
Coleoptera Coccinellidae Scymnus (Neopullus) hoffmani
Weise
Hymenoptera Chalcididae Dirhinus auratus Ashmead
Psilochalcis carinigena
(Cameron)

Hymenoptera Diapriidae Oxypria sp.
Elasmidae Elasmus binocellatus Mani &
Saraswat
E. Indicoides Mani & SaraswatE. Indicoides Mani & Saraswat
Encyrtidae Copidosomyia ambiguous
(Subba Rao)
Doliphoceras sp.
Eulophidae Hemitarsinus sp.
Platygasteridae Amitus sp.
Pteromalidae Norbanus sp.
Spalangia endius (Ashmead)

Hymenoptera Pteromalidae Trichomalopsis nigra Saraswat
& Mani& Mani
Scelionidae Calliscelio sp.
Ceratobaeus sp.
Holoteleia sp.
Leptoteleia sp.
Psilanteris sp.

New Records of Insects and mites from
rice ecosystem in India during the study
Order/
Sub order
Family Genus/species
Insect
Hymenoptera Braconidae Dolichogenidia sp.
Eurytomidae Eurytoma quadrispina NarendranEurytomidae Eurytoma quadrispina Narendran
Mites
Acari
Mesostigmata Ascidae Lasioseius parberlesei
Bhattacharyya

ecosystem in Tamil Nadu during the study
Hymenoptera Bethylidae Bethylus sp.Hymenoptera Bethylidae Bethylus sp.
Braconidae Ademon sp.
Orgilonia sp.
Ceraphronidae Aphanogmus sp.
Scelionidae Macroteleia chandelii Sharma

New Records of spiders from rice
Araneidae Araneus inustus (C.L. Koch)
Cyclosa sp.
Cyrtophora citricola (Forskal)
Neoscona elliptica (Tikader & Bal)Neoscona elliptica (Tikader & Bal)
Neoscona nautica (L. Koch)
Argiopidae Argiope aemula (Walckenaer)
Clubionidae Oedignatha microsculata Reimoser
Corinnidae Castianeira zetes Simon
Castianeira sp.
Eusparassidae Heteropoda sp.

Gnaphosidae Zelotes sp.
Linyphiidae Atypena adelinae Barrion & Litsinger
Atypena spp. 1 - 3
Erigone bifurca LocketErigone bifurca Locket
Lycosidae Arctosa sp.
Lycosa madani Pocock
Pardosa amkhaensis Tikader
Pardosa mackenziei (Gravely)
Pardosa sp. 1
Miturgidae Cheiracanthium danieli Tikader

Oxyopidae Oxyopes birmanicus Tikader
Philodromidae Thanatus parangvulgaris Barrion &
Litsinger
Salticidae Bianor albobimaculatus ProszynskiSalticidae Bianor albobimaculatus Proszynski
Bianor carli Reimoser
Cosmophasis sp.
Epeus sp.
Hasarius sp.
Hyllus pudicus Thorell
Hyllus diardi (Walckenaer)

Salticidae Hyllus semicupreus Simon
Myrmarachne maratha Tikader
Myrmarachne orientalis Tikader
Myrmarachne sp.Myrmarachne sp.
Phintella vittata Koch
Plexippus petersi (Karsch)
Tetragnathidae Dyschirognatha hawigtenera Barrion
& Litsinger
Tetragnatha nitens (Audouin)
Tetragnatha virescens Okuma

New Records of spiders from rice ecosystem
in Tamil Nadu/India during the study
Theridiidae Achaearanea durgae Tikader
Coleosoma floridanum Banks#
Dipoena ruedai Barrion & LitsingerDipoena ruedai Barrion & Litsinger
Enoplognatha sp.
Theridion manjithar Tikader
Theridion tikaderi Patel
Thomisidae Runcinia sp.
# New Record for India

Fig. 2. Distribution of insects in rice ecosystems in N.E. zone of Tamil Nadu
T hysano ptera
Odo nata
N euro ptera
D ermaptera
M anto dea
Ephemero ptera
C o llembo la
P so co ptera
Orders
No. of families No. of species
0 10 20 30 40 50 60 70 80 90
H ymeno ptera
C o leo ptera
H o mo ptera
H emiptera
Lepido ptera
D iptera
Ortho ptera
Orders
No. of families/species

Fig. 3. Distribution of spiders in rice ecosystems in N.E. zone of Tamil Nadu
C o rinnidae
Oxyo pidae
T ho misidae
Eusparassidae
Gnapho sidae
M etidae
M iturgidae
P hilo dro midae
Family
0 2 4 6 8 10 12 14 16 18
Salticidae
Lyco sidae
A raneidae
T etragnathidae
T heridiidae
Linyphiidae
A rgio pidae
C lubio nidae
Family
No. of species

BIODIVERSITY INDICES: α Biodiversity
# 3 Richness Indices:
Hill’s number (N0)
Margalef index (R1)
Menhinick index (R2),
# 4 Diversity Indices
Simpson’s index (l)
Shannon’s index (H’)
Hill’s diversity No. 1 (N1) & No. 2 (N2)
# 5 Evenness Indices (E1 to E5)
were used for quantification of
arthropod biodiversity

Indices Days after planting
9 16 23 30 37 45 61 66 73
Hill's No. (N0) 5 10 11 16 13 18 9 14 10
Margalef's (R1) 1.21 2.17 2.35 3.78 2.62 3.66 2.06 2.99 2.31
Menhinick (R2) 0.96 1.26 1.31 2.2 1.32 1.77 1.29 1.6 1.43
Simpson (λλλλ) 0.62 0.37 0.46 0.17 0.32 0.28 0.26 0.22 0.26
Table 3. Biodiversity indices of arthropods in rice field in Kovur observed
by visual count (IPM field) – Navarai 2002 (12th Feb – 17th Apr)
Shannon (H’) 0.83 1.42 1.34 2.21 1.67 1.9 1.69 1.92 1.71
Hill's Div.No.1 (N1) 2.28 4.13 3.83 9.16 5.32 6.66 5.43 6.79 5.51
Hill’s Div. No. 2 (N2) 1.62 2.73 2.15 5.91 3.12 3.59 3.84 4.55 3.78
E1 0.51 0.62 0.56 0.8 0.65 0.66 0.77 0.73 0.74
E2 0.46 0.41 0.35 0.57 0.41 0.37 0.6 0.48 0.55
E3 0.32 0.35 0.28 0.54 0.36 0.33 0.55 0.45 0.50
E4 0.71 0.66 0.56 0.65 0.59 0.54 0.71 0.67 0.69
E5 0.48 0.55 0.41 0.6 0.49 0.46 0.64 0.61 0.62

12 16 23 32 37 45 61 66
Hill's No. (N0) 6 9 9 9 13 12 13 11
Margalef's (R1) 1.46 1.96 1.97 2.23 3.1 3.09 3.01 2.52
Menhinick (R2) 1.08 1.17 1.18 1.5 1.88 2.03 1.77 1.51
Simpson (λλλλ) 0.71 0.55 0.45 0.28 0.3 0.21 0.16 0.17
by visual count (Non-IPM field) – Navarai 2002 (15th Feb – 10th Apr)
Shannon (H’) 0.7 1.07 1.28 1.65 1.77 1.96 2.16 2.04
Hill's Div.No.1 (N1) 2.02 2.93 3.58 5.18 5.86 7.13 8.68 7.66
Hill’s Div. No. 2 (N2) 1.41 1.83 2.21 3.56 3.31 4.69 6.31 5.89
E1 0.39 0.49 0.58 0.75 0.69 0.79 0.84 0.85
E2 0.34 0.33 0.4 0.58 0.45 0.59 0.67 0.7
E3 0.2 0.24 0.32 0.52 0.41 0.56 0.64 0.67
E4 0.7 0.62 0.62 0.69 0.56 0.66 0.73 0.77
E5 0.4 0.43 0.47 0.61 0.48 0.6 0.69 0.73

Navarai 2002
IPM FIELD:
• Richness Indices showed 3 peaks (30, 45 & 73 DAP)
• Diversity Indices: Maximum diversity on 30 DAP
• Evenness Indices fluctuated throughout the
season.
NON-IPM FIELD:
• Richness Indices remained low till 32 DAP &
reached a peak on 37 DAP
• Diversity Indices gradually increased & attained
the peak on 61 DAP.
• Evenness Indices E1, E2 & E3 showed increasing
trend in the cropping season.
• E4 & E5 fluctuated between 0.56 to 0.77 & 0.4 to
0.73, resp.

11 18 25 32 46 53 60 67 74
Hill's No. (N0) 6 8 10 14 15 17 16 12 12
Margalef's (R1) 1.89 2.52 2.41 3.06 2.58 3.17 2.68 1.91 2.41
Menhinick (R2) 1.60 2.00 1.54 1.67 1.00 1.36 0.98 0.67 1.22
Simpson (λλλλ) 0.19 0.18 0.16 0.17 0.37 0.20 0.22 0.20 0.19
by visual count (IPM field) – Sornavari 2002 (4th Jun – 6th Aug)
Shannon (H’) 1.71 1.89 1.98 2.12 1.45 2.04 1.89 1.85 2.00
Hill's Div.No.1 (N1) 5.53 6.62 7.27 8.36 4.28 7.69 6.63 6.37 7.36
Hill’s Div. No. 2 (N2) 5.16 5.57 6.17 6.03 2.72 4.96 4.64 5.08 5.28
E1 0.95 0.91 0.86 0.80 0.54 0.72 0.68 0.75 0.80
E2 0.92 0.83 0.73 0.60 0.29 0.45 0.41 0.53 0.61
E3 0.91 0.80 0.70 0.57 0.23 0.42 0.38 0.49 0.58
E4 0.93 0.84 0.85 0.72 0.63 0.65 0.70 0.80 0.72
E5 0.92 0.81 0.82 0.68 0.52 0.59 0.65 0.76 0.67

11 18 25 32 46 53 60
Hill's No. (N0) 7 10 11 9 12 12 10
Margalef's (R1) 2.12 3.62 2.79 2.01 2.10 2.04 1.70
Menhinick (R2) 1.70 2.89 1.83 1.24 0.88 0.81 0.71
Simpson (λλλλ) 0.24 0.11 0.12 0.19 0.51 0.46 0.31
by visual count (Non-IPM field) – Sornavari 2002 (4th Jun – 23rd Jul)
Shannon (H’) 1.65 2.25 2.22 1.84 1.15 1.30 1.50
Hill's Div.No.1 (N1) 5.19 9.52 9.18 6.31 3.15 3.68 4.48
Hill’s Div. No. 2 (N2) 4.19 9.00 8.20 5.27 1.94 2.19 3.27
E1 0.85 0.98 0.92 0.84 0.46 0.52 0.65
E2 0.74 0.95 0.83 0.70 0.26 0.31 0.45
E3 0.70 0.95 0.82 0.66 0.20 0.24 0.39
E4 0.81 0.94 0.89 0.84 0.62 0.60 0.73
E5 0.76 0.94 0.88 0.80 0.44 0.44 0.65

Sornavari 2002
IPM FIELD
• Richness Indices N0 & R1 reached peak
during middle of the season on 53 DAP
• 2 Diversity Indices H’ & N1 gradually
increased, reached a peak on 32 DAP
• Other 2 diversity indices λλλλ & N2 reached the• Other 2 diversity indices λλλλ & N2 reached the
peak on 25 DAP itself
NON-IPM FIELD
• Maximum Richness (R1= 3.62 & R2= 2.89)
was observed on 18 DAP
• Diversity was also maximum (λλλλ = 0.11, H’ =
2.25, N1 = 9.52 & N2 = 9.00) on 18 DAP

12 19 26 33 40 48 54 61 68 76 82
Hill's No. (N0) 6 12 12 11 13 11 14 14 13 14 21
Margalef's (R1) 1.43 2.49 2.21 2.10 2.49 1.87 2.53 2.80 2.49 2.93 4.34
Menhinick (R2) 1.04 1.32 1.00 1.02 1.16 0.76 1.07 1.37 1.17 1.52 2.10
Simpson (λλλλ) 0.32 0.32 0.48 0.37 0.36 0.52 0.50 0.14 0.19 0.12 0.12
by visual count (IPM field) – Samba 2002 (1st Oct – 10th Dec.)
Shannon (H’) 1.35 1.65 1.27 1.52 1.60 1.19 1.28 2.24 2.00 2.29 2.54
Hill's Div.No.1 (N1) 3.85 5.19 3.57 4.56 4.96 3.28 3.60 9.43 7.41 9.87 12.65
Hill’s Div. No. 2 (N2) 3.08 3.14 2.10 2.68 2.80 1.94 1.99 7.40 5.24 8.37 8.09
E1 0.75 0.66 0.51 0.63 0.62 0.50 0.49 0.85 0.78 0.87 0.83
E2 0.64 0.43 0.30 0.41 0.38 0.30 0.26 0.67 0.57 0.70 0.60
E3 0.57 0.38 0.23 0.36 0.33 0.23 0.20 0.65 0.53 0.68 0.58
E4 0.80 0.60 0.59 0.59 0.56 0.59 0.55 0.78 0.71 0.85 0.64
E5 0.73 0.51 0.43 0.47 0.45 0.41 0.38 0.76 0.66 0.83 0.61

8 15 22 29 36 43 51 57 64 71 78
Hill's No. (N0) 4 11 9 12 11 13 13 13 13 12 8
Margalef's (R1) 1.11 3.03 2.04 2.30 2.12 2.13 2.07 2.43 3.02 3.38 2.52
Menhinick (R2) 1.03 2.12 1.27 1.10 1.03 0.78 0.72 1.10 1.79 2.35 2.00
Simpson (λλλλ) 0.38 0.17 0.27 0.51 0.40 0.65 0.70 0.49 0.12 0.14 0.29
by visual count (Non-IPM field) – Samba 2002 (24th Sept – 4th Dec.)
Shannon (H’) 1.14 2.02 1.67 1.27 1.39 0.92 0.75 1.24 2.28 2.22 1.65
Hill's Div.No.1 (N1) 3.12 7.57 5.31 3.55 4.00 2.50 2.12 3.47 9.75 9.16 5.19
Hill’s Div. No. 2 (N2) 2.65 5.74 3.71 1.96 2.48 1.54 1.43 2.04 8.24 7.35 3.46
E1 0.82 0.84 0.76 0.51 0.58 0.36 0.29 0.48 0.89 0.89 0.79
E2 0.78 0.69 0.59 0.30 0.36 0.19 0.16 0.27 0.75 0.76 0.65
E3 0.71 0.66 0.54 0.23 0.30 0.12 0.09 0.21 0.73 0.74 0.60
E4 0.85 0.76 0.70 0.55 0.62 0.62 0.68 0.59 0.84 0.80 0.67
E5 0.78 0.72 0.63 0.37 0.49 0.36 0.39 0.42 0.83 0.78 0.59

Samba 2002
IPM FIELD:
Richness Indices were initially very low on 5
DAP, but increased & fluctuated till 76 DAP and
reached the peak on 82 DAP.
Likewise, Diversity Indices were initially low
but fluctuated & reached the peak on 82 DAP.
Evenness Indices were initially high, but theyEvenness Indices were initially high, but they
declined & reached the lowest during 54 DAP.
NON-IPM FIELD:
Richness Indices initially increased by 15 DAP
but declined & fluctuated till 57 DAP.
Peak diversity was attained on 64 DAP
Evenness Indices were initially high on 8 & 15
DAP and gradually declined.

17 24 31 38 45 53 59 66 73
Hill's No. (N0) 10 15 15 17 17 20 13 15 13
Margalef's (R1) 2.49 3.24 3.11 3.89 3.43 4.20 2.66 2.90 2.59
Menhinick (R2) 1.64 1.73 1.58 2.18 1.65 2.09 1.36 1.34 1.29
Simpson (λλλλ) 0.31 0.19 0.21 0.23 0.15 0.14 0.20 0.14 0.20
by visual count (IPM field) – Navarai 2003 (18th Feb – 15th Apr)
Shannon (H’) 1.64 2.01 1.95 1.87 2.26 2.38 1.96 2.18 1.96
Hill's Div.No.1 (N1) 5.18 7.50 7.06 6.49 9.57 10.84 7.13 8.83 7.09
Hill’s Div. No. 2 (N2) 3.27 5.29 4.75 4.31 6.82 7.21 5.03 6.91 5.02
E1 0.71 0.74 0.72 0.66 0.80 0.80 0.77 0.80 0.76
E2 0.52 0.50 0.47 0.38 0.56 0.54 0.55 0.59 0.55
E3 0.46 0.46 0.43 0.34 0.54 0.52 0.51 0.56 0.51
E4 0.63 0.71 0.67 0.66 0.71 0.67 0.71 0.78 0.71
E5 0.54 0.66 0.62 0.60 0.68 0.63 0.66 0.75 0.66

15 22 29 36 43 50 57 63 71 85
Hill's No. (N0) 4 4 17 12 12 14 17 20 18 10
Margalef's (R1) 1.17 0.92 3.75 2.67 2.49 2.59 3.57 4.13 3.10 3.11
Menhinick (R2) 1.11 0.78 2.02 1.52 1.32 1.14 1.81 2.01 1.16 2.36
Simpson (λλλλ) 0.43 0.52 0.16 0.21 0.18 0.12 0.20 0.18 0.29 0.12
Table 10. Biodiversity indices of arthropods in rice field in Kovur
observed by visual count (IPM field) – Sornavari 2003 (10th Jun – 19th Aug)
Shannon (H’) 1.07 0.89 2.18 1.92 1.97 2.25 2.03 1.93 1.79 2.22
Hill's Div.No.1 (N1) 2.92 2.45 8.86 6.85 7.15 9.51 7.64 6.88 5.99 9.17
Hill’s Div. No. 2 (N2) 2.32 1.91 6.16 4.87 5.49 8.02 5.04 5.52 3.39 8.53
E1 0.77 0.65 0.77 0.77 0.79 0.85 0.72 0.64 0.62 0.96
E2 0.73 0.61 0.52 0.57 0.60 0.68 0.45 0.34 0.33 0.92
E3 0.64 0.48 0.49 0.53 0.56 0.65 0.41 0.31 0.29 0.91
E4 0.79 0.78 0.69 0.71 0.77 0.84 0.66 0.80 0.57 0.93
E5 0.68 0.63 0.66 0.66 0.73 0.82 0.61 0.77 0.48 0.92

Indices Navarai 2002 Sornavari 2002 Samba 2002 Navarai
2003
Sornavar
i 2003
F value
IPM N-IPM IPM N-IPM IPM N-IPM IPM IPM
Hill's (N0) 12.83 10.83 13.33 10.67 12.17 11.50 15.67 10.50 1.78 NS
Marg. (R1) 2.77 2.56 2.74 2.38 2.28 2.28 3.39 2.27 2.13 NS
Men. (R2) 1.53 1.59 1.43 1.39 1.06 1.17 1.81 1.32 1.43 NS
Simp. (λλλλ) 0.31abc 0.33abc 0.22c 0.28bc 0.43ab 0.45a 0.21c 0.27c 2.49 *
Shan. (H’) 1.71 1.65 1.90 1.71 1.42 1.34 2.02 1.71 1.97 NS
Table 11. Biodiversity indices of arthropods in rice field in Kovur during
different seasons observed by visual count
Shan. (H’) 1.71 1.65 1.90 1.71 1.42 1.34 2.02 1.71 1.97 NS
Hill's (N1) 5.76 5.56 6.81 6.05 4.19 4.18 7.77 6.29 2.01 NS
Hill’s (N2) 3.56abc 3.65abc 5.02a 4.98a 2.44 c 2.81bc 5.28a 4.80ab 2.35 *
E1 0.68 0.69 0.75 0.73 0.57 0.56 0.74 0.77 2.19 NS
E2 0.45 0.50 0.55 0.58 0.35 0.38 0.50 0.62 2.12 NS
E3 0.40 0.45 0.52 0.54 0.29 0.32 0.46 0.56 2.03 NS
E4 0.62de 0.65cde 0.73abc 0.77a 0.58e 0.66cde 0.68bcd 0.76ab 4.98 **
E5 0.53cd 0.55bcd 0.68ab 0.69ab 0.44d 0.49d 0.62abc 0.70a 4.29 **

Biodiversity
Indices
Seasons
Navarai
2002
Sornavari
2002
Samba
2002
Navarai
2003
Sornavari
2003
F Ratio
Hill's No. (N0) 12.83 13.33 12.17 15.67 10.50 1.62 NS
Margalef's (R1) 2.77ab 2.74ab 2.28a 3.39b 2.27a 2.75*
Menhinick (R2) 1.53ac 1.43abc 1.06b 1.81c 1.32ab 4.15**
Simpson (λλλλ) 0.31ab 0.22a 0.43b 0.21a 0.27a 3.03*
Table 13. Biodiversity indices of arthropods in rice field in
Kovur observed by visual count (IPM field) – All Seasons
Shannon (H’) 1.71 1.90 1.42 2.02 1.71 2.43 NS
Hill's Div.No.1 (N1) 5.76 6.81 4.19 7.77 6.29 2.68 NS
Hill’s Div. No. 2 (N2) 3.56 5.02 2.44 5.28 4.80 2.67 NS
E1 0.68ab 0.75b 0.57a 0.74b 0.77b 2.97*
E2 0.45 0.55 0.35 0.50 0.62 2.46 NS
E3 0.40ab 0.52bc 0.29a 0.46bc 0.56c 4.79**
E4 0.62ab 0.73cd 0.58a 0.68bc 0.76d 10.39**
E5 0.53a 0.68b 0.44a 0.62b 0.70b 12.02**

ALL 5 SEASONS
IPM & NON-IPM FIELDS
• Richness: Richness Indices did not differ
significantly among the seasons as well as
between the IPM & non-IPM fields.
• Diversity: Only two diversity indices were
statistically significant, viz., Simpson’s index (λλλλ) &statistically significant, viz., Simpson’s index (λλλλ) &
Hill’s diversity No. 2 (N2).
• Between IPM & non-IPM fields, there was no
significant difference in diversity.
• However, among seasons, Samba 2002 had
significantly lower diversity than Sornavari
season. In 2003, no significant difference between
Navarai & Sornavari seasons.

• Only E4 & E5 were statistically significant.
• Between IPM & non-IPM fields, there was no
significant difference in evenness.
• Among the seasons in 2002, Sornavari
Evenness
recorded significantly higher evenness (E5
= 0.68) compared to Navarai (E5 = 0.53) &
Samba (E5 = 0.44) seasons.
• No marked difference in evenness between
Navarai & Sornavari seasons in 2003.

Indices Navarai
2002
Sornavari
2002
Samba
2002
Navarai
2003
Sornavari
2003
IPM Non-
IPM
IPM Non-
IPM
IPM Non-
IPM
IPM IPM
Table 12. Expected number of species E(Sn) during different seasons in
Kovur rice fields based on rarefraction method
E(S48) 12 - 11 7 16 7 15 12
Actual
maximum no. of
species
recorded
18 13 17 12 21 13 20 20
Total no. of
individuals per
25 hills
104 48 156 186 100 281 92 99

RAREFRACTION METHOD
• Highest E (Sn) of 16 was recorded in the IPM
fields in Samba 2002.
• Lowest E (Sn) of 7 recorded in Sornavari
2002 season in the non-IPM field.
RICHNESS:RICHNESS:
Margalef index (R1) & Menhinick index
(R2) were statistically significant.
Richness of Navarai 2003 season was
significantly higher than Samba 2002 and
Sornavari 2003

DIVERSITY
• Only Simpson’s index (λλλλ) was
statistically significant.
• In 2002, Samba season had
significantly lower diversity thansignificantly lower diversity than
Sornavari season.
• In 2003, there was no significant
difference between Navarai &
Sornavari.

Evenness
• Among the 5 evenness indices, all but
E2 were statistically significant.
• In 2002, Sornavari recorded significantly
higher evenness compared to Navarai &
Samba.Samba.
• In E1 and E3 indices the Sornavari 2002
was superior than Samba 2002.
• In 2003, there was significant difference
in evenness between Navarai &
Sornavari, only in the case of E4.

Vallam observed by visual count (Semidry rice-cv. BPT 5204) –
Samba 2002
20 27 34 41 46 54 61 69 83 91 105 119
Hill's No. (N0) 7 7 5 8 12 17 19 15 12 20 15 16
Margalef's (R1) 2.52 3.23 2.55 2.9 3.52 4.54 5.1 3.34 2.65 4.32 2.82 2.54
Menhinick (R2) 2.13 2.77 2.28 2.39 2.51 2.92 3.26 1.85 1.51 2.21 1.25 0.84
Days after sowingBiodiversity
Indices
Diversity
Richness
Simpson (l) 0.19 0.22 0.26 0.18 0.14 0.13 0.09 0.25 0.28 0.22 0.18 0.26
Shannon (H') 1.81 1.72 1.45 1.88 2.16 2.33 2.58 1.91 1.76 2 2.02 1.63
Hill's Div.No.1 (N1) 6.08 5.59 4.24 6.54 8.65 10.3 13.2 6.74 5.8 7.36 7.51 5.12
Hill's Div.No.2 (N2) 5.4 4.57 3.79 5.68 7.02 7.5 10.9 3.94 3.54 4.62 5.48 3.86
E1 0.93 0.88 0.9 0.9 0.87 0.82 0.88 0.7 0.71 0.67 0.74 0.59
E2 0.87 0.8 0.85 0.82 0.72 0.6 0.7 0.45 0.48 0.37 0.5 0.32
E3 0.85 0.77 0.81 0.79 0.7 0.58 0.68 0.41 0.44 0.33 0.47 0.27
E4 0.89 0.82 0.89 0.87 0.81 0.73 0.83 0.58 0.61 0.63 0.73 0.75
E5 0.87 0.78 0.86 0.84 0.79 0.7 0.81 0.51 0.53 0.57 0.69 0.69
Evenness
Diversity

Nursery - Different locations
• Among the 10 villages, Kavarapettai
(cv. ADT 43) recorded the maximum
richness (N0 = 42; R1 = 5.25).
• It was followed by cv. ADT 36 in the
same village.
• Pesticide applied fields had lower• Pesticide applied fields had lower
richness than the no pesticide fields.
• Lowest richness was recorded in the
pesticide-applied field in Malaiyam-
bakkam (cv. ADT 43) (N0 = 20; R1 =
2.82).

Table 15. Biodiversity indices of arthropods in rice
field in Kovur observed by net sweeps (IPM field) –
Sornavari 2003
15 22 29 36 43 50 57 63 71
Hill's No. (N0) 9 21 19 20 20 24 23 17 18
Margalef's (R1) 1.44 2.83 2.32 3.03 3.09 3.55 2.74 2.18 2.92
Menhinick (R2) 0.56 0.62 0.39 0.87 0.93 0.94 0.41 0.43 0.98
Days after plantingBiodiversity
Indices
Richness
Diversity
Simpson (l) 0.64 0.31 0.29 0.17 0.15 0.18 0.45 0.69 0.2
Shannon (H') 0.83 1.48 1.43 2.01 2.15 2.14 1.23 0.84 2.03
Hill's Div.No.1 (N1) 2.28 4.38 4.19 7.43 8.57 8.47 3.43 2.32 7.64
Hill's Div.No.2 (N2) 1.57 3.24 3.42 5.79 6.69 5.58 2.23 1.45 4.95
E1 0.38 0.49 0.49 0.67 0.72 0.67 0.39 0.3 0.7
E2 0.25 0.21 0.22 0.37 0.43 0.35 0.15 0.14 0.42
E3 0.16 0.17 0.18 0.34 0.4 0.32 0.11 0.08 0.39
E4 0.69 0.74 0.82 0.78 0.78 0.66 0.65 0.62 0.65
E5 0.44 0.66 0.76 0.75 0.75 0.61 0.51 0.34 0.59
Evenness
Diversity

Kovur observed by net sweeps
(Non-IPM field) – Sornavari 2003
15 22 29 36 43 50
Hill's No. (N0) 22 31 29 27 26 19
Margalef's (R1) 3.59 4.14 4.15 4.33 4.12 2.84
Menhinick (R2) 1.18 0.83 1 1.34 1.25 0.8
Biodiversity Indices
Days after planting
Richness
Diversity
Simpson (l) 0.35 0.5 0.36 0.24 0.19 0.26
Shannon (H') 1.57 1.29 1.57 2.01 2.14 1.84
Hill's Div.No.1 (N1) 4.82 3.65 4.82 7.44 8.52 6.32
Hill's Div.No.2 (N2) 2.84 2.01 2.79 4.16 5.19 3.8
E1 0.51 0.38 0.47 0.61 0.66 0.63
E2 0.22 0.12 0.17 0.28 0.33 0.33
E3 0.18 0.09 0.14 0.25 0.3 0.3
E4 0.59 0.55 0.58 0.56 0.61 0.6
E5 0.48 0.38 0.47 0.49 0.56 0.53
Evenness
Diversity

Table 17. Biodiversity indices of arthropods in rice
nursery fields in different villages observed by net
sweeps – Sornavari 2003
17-May-03 20-May-03 23-May-03 27-May-03 30-May-03 30-May-03 20-Jun-03 23-May-03 27-May-03 06-Jun-03
(N0) 29 29 27 29 42 35 27 23 20 29
Richness
Kovur
(IPM
Field)
Kavarapettai
(cv. ADT 43)
Kavarapettai
(cv. ADT 36)
Biodiversity
Indices
No pesticide Fields Pesticide applied Fields
Budur Narasinga-
puram
Malai-
yambakkam
Nan-
mangalam
Kovur
(Non-IPM
Field)
Malai-
yambakkam
Sentha-
mangalam
(R1) 3.68 3.74 4.31 3.96 5.25 4.48 3.77 4.12 2.82 3.7
(R2) 0.65 0.69 1.33 0.84 0.85 0.79 0.86 1.59 0.69 0.66
(λλλλ) 0.46 0.18 0.34 0.28 0.19 0.15 0.32 0.38 0.36 0.33
(H’) 1.35 2.08 1.73 1.82 2.16 2.26 1.77 1.7 1.35 1.71
(N1) 3.87 7.99 5.62 6.18 8.68 9.59 5.87 5.49 3.85 5.54
(N2) 2.19 5.41 2.93 3.54 5.35 6.48 3.14 2.66 2.8 3.02
E1 0.4 0.62 0.52 0.54 0.58 0.64 0.54 0.54 0.45 0.51
E2 0.13 0.28 0.21 0.21 0.21 0.27 0.22 0.24 0.19 0.19
E3 0.1 0.25 0.18 0.19 0.19 0.25 0.19 0.2 0.15 0.16
E4 0.56 0.68 0.52 0.57 0.62 0.68 0.54 0.49 0.73 0.55
E5 0.41 0.63 0.42 0.49 0.57 0.64 0.44 0.37 0.63 0.45
Diversity
Evenness

Table 18. Expected number of species E(Sn) in
nursery fields based on rarefraction method
17/05/03 20/05/03 23/05/03 27/05/03 30/05/03 30/05/03 20/06/03 23/05/03 27/05/03 06/06/03
E (S 209) 14 17 19 a 16 20 19 17 - 11 17
Actual no. of
29 29 27 29 42 35 27 23 20 29
Biodiversity
Indices
No pesticide Fields Pesticide applied Fields
Budur
Narasinga-
puram
Malai-
yambakkam
Sentha-
mangalam
Kovur (Non-
IPM Field)
Malai-
yambakkam
Kovur
(IPM field)
Kavarapettai
(cv. ADT 43)
Kavarapettai (cv.
ADT 36)
Nan-
mangalam
Actual no. of
species recorded 29 29 27 29 42 35 27 23 20 29
Total no. of
individuals per 50
sweeps 2020 1786 414 1181 2463 1974 981 209 847 1927
Note: a – the maximum possible value for n < {N – max
(Ni)}; for the current data n should be < 184 hence no.
of species worked out at E(S183)

Expected number of species E (Sn)
• Highest E (Sn) of 20 recorded in
Kavarapettai (cv. ADT 43) in no
pesticide fields (sample of n = 209)
• Also corresponded with the highest N0• Also corresponded with the highest N0
of 42 recorded in the same field.
• Lowest E (Sn) of 11 recorded in the
Malaiyambakkam pesticide applied
field; lowest N0 of 20 recorded in the
same field.

Fig. 8. Arthropod guilds in rice nurseries in various
locations during Sornavari 2003
Ko vur
Senthamangalam
M alaiyambakkam
Ko vur Pest Predator Parasitoids Neutrals
0 500 1000 1500 2000 2500 3000
Kavarapettai
B udur
N arasingapuram
M alaiyambakkam
Ko vur
Population per 50 sweeps

Table 20. Qualitative similarity indices between IPM and
non-IPM fields in Kovur village during Navarai,
Sornavari and Samba 2002 seasons
I II III IV V VI VII VIII IX X Mean+ SD
Jaccard
Index 0.19 0.54 0.17 0.63 0.5 0.47 0.47 0.42 + 0.18
Navarai 2002
Season/
Index
Similarity Indices (Weeks after planting)
Index 0.19 0.54 0.17 0.63 0.5 0.47 0.47 0.42 + 0.18
Sorensen
Index 0.32 0.7 0.3 0.77 0.67 0.64 0.64 0.57 + 0.19
Jaccard
Index 0.63 0.5 0.75 0.44 0.42 0.53 0.63 0.56 + 0.12
Sorensen
Index 0.77 0.67 0.86 0.61 0.59 0.69 0.77 0.71 + 0.10
Jaccard
Index 0.43 0.57 0.5 0.64 0.71 0.5 0.59 0.42 0.63 0.53 0.54 + 0.10
Sorensen
Index 0.6 0.73 0.67 0.78 0.83 0.67 0.74 0.59 0.77 0.69 0.69 + 0.09
Sornavari 2002
Samba 2002

β BIODIVERSITY:
Qualitative Similarity Indices
• Similarity of taxa between IPM & non-IPM
fields was tested using Jaccard & Sorensen
Indices. Sornavari 2002 recorded the
maximum mean similarity followed bymaximum mean similarity followed by
Samba 2002 & Navarai 2002.
• In Sornavari 2002, the mean similarity
values were higher than in Navarai & Samba
• Mean similarity indices were higher in
Samba 2002.

Devarassou & Adiroubane (2005)
studied the biodiversity of arthropod
fauna in IPM & non-IPM fields in
Karaikal
Species richness,Species richness,
Diversity indices and
Evenness indices
were higher in IPM field than non-
IPM field.

In Kerala, species diversity was
low in Kuttanad rice ecosystem,
where pesticides were applied
rampantly
It was moderate in Trivandrum dt.,
where pesticides were appliedwhere pesticides were applied
judiciously
It was highest in Pokkali in
Ernakulam dt., where no
insecticides were applied (Premila
et al., 2003).

PRACTICES ON THE
BIODIVERSITY

PRACTICES ON THE BIODIVERSITY
• Effects of different agronomic
practices, viz.,
fertilizer,
chemical pesticide andchemical pesticide and
botanical pesticide applications
were studied in Kovur during
Navarai 2002, Sornavari 2002 &
Sornavari 2003, & in Budur during
late Navarai 2003.

Table 21. Relative abundance of pests and predators
in rice fields in Kovur during three seasons
(Navarai 2002 – Samba 2002)
IPM Non-IPM IPM Non-IPM IPM Non-IPM
Pests
Brown planthopper 2.11 1.94 17.16 17.94 10.3 7.03
White-backed planthopper 0.16 1.94 22.97 49.51 45.55 67.01
Pests/Predators
Weekly mean relative abundance (%)
Navarai 2002 Sornavari 2002 Samba 2002
White-backed planthopper 0.16 1.94 22.97 49.51 45.55 67.01
Green leaf hopper 3.68 5.7 3.14 5.15 2.13 1.28
Black bug 1.02 1.08 0.89 1.66 1.53 2.92
Grasshopper 3.99 4.3 2.5 2.08 3.43 1.11
Predators
Web spiders 56.93* 55.16* 26.59 9.18 10.91 4.63
Jumping spiders - - 3.22 2.08 2.36 1.37
Hunting spiders - - 6.85 6.26 9.61 5.92
Mirid bug 0.55 0.86 7.74 1.53 3.96 0.86
Ophionea indica 0.55 0.86 1.29 0 2.13 1.72
Rove beetle 5.95 0.86 0.73 0.14 0.07 0.08
Micraspis discolor complex. 15.11 12.37 3.38 0.97 2.21 2.4

Fig. 4. Effect of carbofuran on spiders in non-IPM rice field during
Navarai 2002
8
10
12
14
Populationper5hills
carbofuran
0
2
4
6
1 2 3 4 5 7 9 10
Weeks after sowing
Populationper5hills
IPM field Non-IPM field

Fig. 5. Effect of carbofuran on Micraspis discolor in non-IPM rice field
during Navarai 2002
3
4
5
6
Populationper5hills
0
1
2
3
1 2 3 4 5 7 9 10
Weeks after sowing
Populationper5hills
IPM field Non-IPM field
carbofuran

Fig. 6. Effect of fertilisers and carbofuran on rice fields in
Kovur during Sornavari 2002
20
25
30
35
40
Populationper5hills
0
5
10
15
1 2 3 4 6 7 8
Weeks after sowing
Populationper5hills
Planthoppers IPM Spiders IPM Planthoppers non-IPM Spiders non-IPM

•Reduction in the population of
spiders due to the application of
carbofuran has been reported by
Kumar and Velusamy (1997b)
• Fertilizers have been cited as one of• Fertilizers have been cited as one of
the major causes for the increased
prevalence of BPH (Abraham and
Nair, 1975; Velusamy et al., 1975;
Kalode, 1976; Visarto et al. 2001) and
WBPH (Majid et al., 1979).

Fig. 7. Effect of monocrotophos and profenophos on leaf folder
incidence and spider population in rice during late Navarai 2003
15
20
25
PopulationperhillorDamage(%)
Monocrotophos
Profenophos
0
5
10
30 37 43 51 65 73
Days after planting
PopulationperhillorDamage(%)
Leaffolder number Leaffolder damage Spider

Several workers have reported
the toxic nature of
monocrotophos to predatory
insects and spiders (Patel et al.,
1997;Geetha and Gopalan, 1998,
Panda et al., 2002).Panda et al., 2002).
Panda et al. (2002) reported that
Profenofos was one of the safest
insecticides for spiders, which
was on a par with the control
(untreated check).

Table 27. Effect of neem oil* on the pests,
entomophages and neutrals of rice in Kovur
IPM
Field
Non-IPM
Field*
IPM
Field
Non-IPM
Field
IPM
Field
Non-IPM
Field
IPM
Field
Non-IPM
Field
22 DAP 29 DAP 29 DAP 36 DAP 36 DAP 43 DAP 43 DAP 50 DAP
Pests
White backed
planthopper 22 24 20 10 5 5 9 14
Green
Taxa
Population / 50 double net sweeps
Pre treatment
17.6.2003
Post treatment
(3 DAT) 24.6.2003
10 DAT
1.7.2003
17 DAT
8.7.2003
Green
leafhopper 22 11 56 24 55 26 36 17
Bemisia
tabaci
233 169 877 85 129 36 59 35
Thrips 276 45 759 21 65 18 29 27
Grasshoppers 2 15 9 19 9 21 23 14
Others 6 14 8 13 2 6 1 1
Predators
Spiders 25 9 22 8 13 7 1 5
Odonata 7 7 12 7 15 10 13 11
Parasitoids
Hymenoptera 25 57 60 23 90 38 78 66
Neutrals
Diptera 534 470 542 174 128 82 93 87

Impact of neem oil on Arthropods- Non-
IPM Field
Taxa/ Group
Pre-
treatment
Post
treatment
%
reduction
Whitefly 169
85
49.7
53.3
Thrips 45 21
53.3
Parasitic
hymenoptera
57 23 59.6
Dipteran flies 470 172
63.4

Effect of neem oil appln. in adjacent field
(Non- IPM field ) on Arthropods in IPM Field
Taxa/ Group
Pre-
treatment
Post
treatment
% increase
Whitefly
233 877 73.4
Thrips
276 759 63.6
Parasitic
hymenoptera
25 60 58.3
Dipteran flies
534 542 1.5

Effect of Neem oil on BeneficialEffect of Neem oil on Beneficial
Rice ArthropodsRice Arthropods
•Safe to Parasites & Predators – TNAU Neem oil
( Ragini & David, 2003)
•Safe to spiders and mirid bugs – NO 3% (Dash et al.,
1996); - NO:Urea 1:10 (Babu et al., 1998)1996); - NO:Urea 1:10 (Babu et al., 1998)
•Predatory spiders reduced by 43.5% in kharif and
27.4% in rabi – NO 3% (Shukla and Kaushik, 1994)
•Initial reduction of L. pseudoannulata and mirid bug;
recolonization better than in plots treated with
monocrotophos (Mohan et al. 1991)

Impact of neem oil application on
arthropods
•Neem oil reduces the incidence of
whitefly and thrips, it also reduces the
number of parasitic hymenoptera andnumber of parasitic hymenoptera and
dipteran flies
•Parasitic hymenoptera reach the
pretreatment level 17 days after treatment
•In the case of the pests the effect of
neem is present till 17DAT

RELATIVE ABUNDANCE
• SPECIES RICHNESS & ABUNDANCE of
predator populations may be greater
than those of the pest populations,
when little or no insecticides are used
(Way and Heong, 1994).(Way and Heong, 1994).
• Bambaradeniya (2000) observed that
more than 50% of the terrestrial
arthropod species consisted of
predators, with spiders being the
dominant group in Sri Lanka.

POPULATION DYNAMICS OF
IMPORTANT ARTHROPODS

Table 38 & 39. Population of pests/predators in rice fields in
Kovur during five seasons (Navarai 2002 – Sornavari 2003)
Navarai Sornavari Navarai Sornavari
2002 2002 2003 2003
Pest
Brown planthopper 0.27 2.25 0.58 3.68
White-backed
Name of Pest/
Predator
Weekly mean population per 5 hills
Samba
2002
4.26
planthopper 0.02 9.95 1.1 1.76
Green leaf hopper 0.47 0.47 0.32 1.32
Grasshopper 0.51 0.75 0.44 0.88
Predator
Web spiders 7.27* 6.6 2.38 5.59 3.04
Jumping spiders - 0.8 0.52 1.14 0.46
Hunting spiders - 1.7 2.1 3.3 3.68
Mirid bug 0.07 1.92 0.87 0.07 1.32
Ophionea indica 0.07 0.32 0.47 0.04 0.18
Rove beetle 0.76 0.18 0.02 0.09 0.04
5.7
0.78
0.62

Table 40. Population of pests in rice IPM field in Kovur
during Sornavari 2003 observed by net sweep
Aug. 03
10th 17th 24th 1st 8th 15th 22nd 28th 5th
Days after planting 15 22 29 36 43 50 57 63 71
PESTS
Orthoptera
ACRIDIDAE 2 9 9 23 55 46 24 40
Homoptera
Date
Jun-03 Jul-03
Homoptera
CICADELLIDAE
Nephotettix virescens 1 22 56 55 36 31 69 47 29
Leafhopper nymphs 3 22 34 15 6
DELPHACIDAE
Nilaparvata lugens 2 1 2 1
Sogatella furcifera 22 20 5 9 16 2 7
ALEYRODIDAE
Bemisia tabaci 4 233 877 129 59 8 9 1
Thysanoptera
Thrips 29 276 759 65 29 124 681 59 13

Table 41. Population of entomophages in rice IPM field in Kovur
during Sornavari 2003 observed by net sweep
Aug. 03
PREDATORS
Araneae 4 25 22 13 1 4 2 6 3
Odonata
Damselfly 4 12 13 12 24 8 5 14
Coleoptera
Date
Jun-03 Jul-03
Coleoptera
Micraspis discolor
complex 2 2 12 36 26 35
Hemiptera
MIRIDAE
Cyrtorhinus
lividipennis 3 2 2 7 4 1
ANTHOCORIDAE 1 1 14 9 5
Acari
ASCIDAE 1 10 110 216 1960 1282 133
PARASITOIDS
Hymenoptera 10 25 60 90 78 86 133 40 16

Table 42. Population of neutrals in rice IPM field in
Kovur during Sornavari 2003 observed by net sweep
Aug. 03
SCIOMYZIDAE 4 6 9 5 2
SYRPHIDAE 1
Other Diptera 201 534 542 124 87 25 97 19 36
BRUCHIDAE 1
CHRYSOMELIDAE 1 1
Date
Jun-03 Jul-03
CHRYSOMELIDAE 1 1
CURCULIONIDAE 1
HYDROPHILIDAE 1
OTHERS 2 2 2
TETRIGIDAE 1
CORIXIDAE 1
PSYLLIDAE 1 1
AGOANIDAE 1
Collembola 2 2 1
Acari
CRYPTOSTIGMATA 3 1 1

Table 43. Population of pests in rice fields in different
villages observed by net sweeps Sornavari 2003
Nan- Venkathur Nandi-
mangalam Kandigai mangalam
Date 2.5.03 9.5.03 20.6.03 27.6.03 27.6.03
ACRIDIDAE 4 3 5
Nephotettix virescens 13 5 2 31 59
Zigzag leaf hopper 1
Blue leaf hopper 1 59 56
Pests Budur
Girugam-
bakkam
Blue leaf hopper 1 59 56
Cicadulina bipunctata 1
Other leaf hoppers 1
Leafhopper nymphs 48 33 34 271
Nilaparvata lugens 1 2
Sogatella furcifera 4 3 1 9 72
Bemisia tabaci 21 5 27 386 546
Thrips 189 62 19 505 296
PYRALIDAE 21 2 3 2
HESPERIDAE 4 1

Table 44. Population of entomophages in rice fields in
different villages observed by net sweep – Sornavari 2003
Girugam- Nan- Venkathur Nandi-
bakkam mangalamKandigai mangalam
Date 2.5.03 9.5.03 20.6.03 27.6.03 27.6.03
PREDATORS
Araneae 12 5 9 32 86
Odonata
Entomophages Budur
Odonata
Damselfly 17 8 5 6 6
Dragonfly 2
Coleoptera
Micraspis discolor complex 43 2 5 15
Cyrtorhinus lividipennis 7 5 5 8
ANTHOCORIDAE 8 2 1 1
Ant 1 9 5
ASCIDAE 2 189 202
PARASITOIDS
Hymenoptera 261 42 11 159 449

Table 45. Population of neutrals in rice fields in different
villages observed by net sweeps – Sornavari 2003
Girugam- Nan- Venkathur Nandi-
bakkam mangalam Kandigai mangalam
Date 2.5.03 9.5.03 20.6.03 27.6.03 27.6.03
Diptera
SCIOMYZIDAE 13 3 1 8
Neutrals Budur
SCIOMYZIDAE 13 3 1 8
Other Diptera 248 56 122 1072
Coleoptera
BRUCHIDAE 3 1
CHRYSOMELIDAE 2
ELATERIDAE 1
HYDROPHILIDAE 3 1 3 2 1
CRYPTOSTIGMATA 14

Table 46. Population of pests in various rice
nurseries by net sweeps-Sornavari 2003
Date 17/05/03 20/05/03 23/05/03 27/05/03 30/05/03 30/05/03 20/06/03 23/05/03 27/05/03 06/06/03
Kavarapettai
(cv.ADT43)
Kavarapettai
(cv.ADT36)
Nan-
mangalam
Kovur
(FieldB)
Malai-
yambakkam
Sentha-
mangalam
Pests
No Pesticide Fields Pesticide applied Fields
Budur
Narasinga-
puram
Kovur
(FieldA)
Malai-
yambakkam
Date 17/05/03 20/05/03 23/05/03 27/05/03 30/05/03 30/05/03 20/06/03 23/05/03 27/05/03 06/06/03
ACRIDIDAE 1 459 59 19 62 208 18 1 42
Nephotettix virescens 12 6 1 5 16 5 3 1 10 14
Zigag leaf hopper 9 6 1 1 13 11 5 1 12
Blue leaf hopper 5 4 48 46 1 1 1 3 28
Other leaf hoppers 1 4 1 6 1 16
Leafhopper nymphs 50 188 16 97 583 145 2 16 36
Nilaparvata lugens 10 1 1 7 2 1
Sogatella furcifera 75 3 10 1 1 2 6
Bemisia tabaci 121 72 3 153 77 47 129 6 241 159
Menida histrio 1 1 17
Thrips 54 113 10 89 53 15 60 17 102 318
PYRALIDAE 21 5 1 4 2 2 2
HESPERIDAE 4 1 5

Table 47. Population of entomophages in various rice
nurseries by net sweeps-Sornavari 2003
Date 17/05/03 20/05/03 23/05/03 27/05/03 30/05/03 30/05/03 20/06/03 23/05/03 27/05/03 06/06/03
PREDATORS
Araneae 16 49 5 26 95 175 29 5 63
Odonata 12 3 14 1 1 1 35 3 3
Pests
Budur
Malai-
yambakkam
Narasinga-
puram
Kovur
(FieldA)
Kovur
(FieldB)
Sentha-
mangalam
Malai-
yambakkam
Kavarapettai
(cv.ADT43)
Kavarapettai
(cv.ADT36)
Nan-
mangalam
Odonata 12 3 14 1 1 1 35 3 3
Coleoptera
Micraspis discolor
complex 2 16 3 5 53 65 3 1 2
Ophionea sp. 1 52 1 7 37 116 32 1 1
Paederus fuscipes 8 3 4 40 4 12
ANTHICIDAE 1 1 4 2
Cyrtorhinus
lividipennis 5 4 2 1 3 2
Brown mirid 1 19 1 1 1 3
Ant 3 21 2 12 1 2 2
VESPIDAE 2 1
TETTIGONIDAE 16
TRIDACTYLIDAE 13 1
Acari - ASCIDAE 10
PARASITOIDS
Hymenoptera 267 188 37 97 361 445 81 12 22 87

Table 48. Population of neutrals in various rice nurseries by
net sweeps - Sornavari 2003
Date 17/05/03 20/05/03 23/05/03 27/05/03 30/05/03 30/05/03 20/06/03 23/05/03 27/05/03 06/06/03
Pests
Budur
Narasinga-
puram
Kovur
(FieldA)
Malai-
yambakkam
Kavarapettai
(cv.ADT43)
Sentha-
mangalam
Kavarapettai
(cv.ADT36)
Nan-
mangalam
Kovur
(FieldB)
Malai-
yambakkam
Date 17/05/03 20/05/03 23/05/03 27/05/03 30/05/03 30/05/03 20/06/03 23/05/03 27/05/03 06/06/03
SCIOMYZIDAE 1 8 1 24 21 4 8
Other Diptera 1330 533 230 583 786 529 528 125 432 1041
APIONIDAE 1 1 1 31 32 1
BRUCHIDAE 3 5 28 2 1
CHRYSOMELIDAE 2 7 1 1 4
CUCUJIDAE 3 5
HYDROPHILIDAE 12 3 5 122 75 19 13 1
TETRIGIDAE 1 10
LYGAEIDAE 1 1 5
TINGIDAE 6
Collembola 24
Acari 2 2 25

Fig. 9e. Composition of guilds in Narasingapuram
400
600
800
1000
Populationper50sweeps
Fig. 9f. Proportion of guilds Narasingapuram
40%
60%
80%
100%
Proportion
Fig. 9. Composition and proportion of different groups
of guilds in rice nursery fields in Narasingapuram
during Sornavari 2003
0
200
Pests Predators Parasitoids Neutrals
Guilds
Grasshopper Hoppers Whitefly
Thrips Lepidopteran pests Other pests
Spiders Mirid bug Ladybird beetles
Other predators Par. Hymenoptera Other parasitoids
Dipterans Beetles Other neutrals
0%
20%
Guilds
Proportion
Grasshopper Hoppers Whitefly
Thrips Lepidopteran pests Other pests
Spiders Mirid bug Ladybird beetles
Other predators Par. Hymenoptera Other parasitoids
Dipterans Beetles Other neutrals

Fig. 9a. Composition of guilds in Budur
800
1000
1200
1400
1600
Fig. 9b. Proportion of guilds in Budur
60%
80%
100%
Proportion
of guilds in rice nursery fields in Budur during
Sornavari 2003
0
200
400
600
800
Guilds
0%
20%
40%
Guilds
Proportion

Fig. 9c. Composition of guilds in Kavarapettai (cv. ADT 43)
800
1000
1200
Fig. 9d. Proportion of guilds in Kavarapettai (cv. ADT 43)
60%
80%
100%
Proportion
of guilds in rice nursery fields in Kavarapettai during
Sornavari 2003
0
200
400
600
Guilds
0%
20%
40%
60%
Guilds
Proportion

Table 49. Comparison between net sweeps and visual
observation in Kovur during Sornavari 2003 season
Net sweep
1
Visual
2
Net sweep
1
Visual
2
Net sweep
1
Visual
2
Pests
Oxya spp. 208 42 2 7 24.38 4.99 0.768
Nephotettix
virescens 346 64 1 5 40.56 7.6 0.306
Nilaparvata
lugens
Relative
abundance Correlation
Coefficient
Taxa/ Group Total individuals
Ranking among
the Taxa
lugens 6 182 7 2 0.7 21.62 0.45
Sogatella
furcifera 81 88 4 3 9.5 10.45 0.059
Predators
Spiders 80 351 5 1 9.38 41.69 -0.382
Micraspis
discolor
complex 113 49 3 6 13.25 5.82 0.717
Cyrtorhinus
lividipennis 19 66 6 4 2.23 7.84 0.479
Note: 1 Total individual for 50 net sweeps
2 Visual observations from 25 hills

Rice Arthropods
Beevi et al. (2003):
• Entomophages, viz., predators and
parasitoids, were the mostparasitoids, were the most
dominant group followed by
phytophages and then the
detritivores in transplanted rice in
six villages in Kerala.

NEUTRAL INSECTS
• Comprised 16.98 & 6.82% of the
total rice arthropod species in early
& late rice fields, resp. (Liu et al., 2002).
• BPH & GLH were the most
abundant pest species in 2 sites of
Orissa & Bihar, resp.Orissa & Bihar, resp.
• Among the natural enemies, mirids &
spiders (Lycosidae & Tetragnathidae)
were the most abundant taxa in both
the states. (Chakraborty et al., 1990).

EFFECTS OF WEATHER FACTORS ON

Table 50. Correlation coefficients of weather factors vs. arthropods
interaction in rice ecosystem in Kovur Village (Navarai 2002)
Pest / Natural
enemy
Max.
Temp.
Min.
Temp.
Rel.
Hum.
Rainfall
Nilaparvata
lugens -0.332 -0.363 -0.374
-
Nephotettix
virescens -0.096 -0.077 0.057
-
Cofana spectra
0.167 0.149 -0.139
-Cofana spectra
0.167 0.149 -0.139
-
Oxya spp.
0.599 0.624 -0.242
-
Web spiders -0.719 -0.503 -0.183
Jumping spiders 0.835* 0.778 -0.548
Hunting spiders -0.849* -0.889* 0.531
Rove beetle -0.797 -0.61 -0.02 -
Micraspis
discolor complex 0.758
*
0.719 0.016
-
Earwig -0.124 -0.163 0.176 -

interaction in rice ecosystem in Kovur Village (Sornavari 2002)
Pest / Natural
enemy
Max.
Temp.
Min.
Temp.
Rel.
Hum.
Rainfall
Nilaparvata
lugens 0.006 -0.069 -0.331 0.023
Sogatella
furcifera 0.534 0.702
*
-0.241 -0.183
Nephotettix
Sornavari 2002
Nephotettix
virescens -0.196 0.058 0.172 -0.107
Oxya spp. -0.358 -0.332 -0.326 0.063
Web spiders -0.188 -0.111 -0.172 0.015
Jumping spiders -0.118 -0.277 0.336 0.893**
Hunting Spiders -0.079 0.233 -0.421 -0.107
Cyrtorhinus
lividipennis 0.136 -0.061 -0.488 0.086

Table 50. Correlation coefficients of weather factors vs.
arthropods interaction in rice ecosystem in Kovur Village
(Samba 2002)
Pest / Natural
enemy
Max.
Temp.
Min.
Temp.
Rel.
Hum.
Rainfall
Nilaparvata
lugens -0.475 -0.515 -0.118 0.071
Samba 2002
Sogatella
furcifera -0.491 -0.012 0.833** 0.920**
Oxya spp. -0.628* -0.509 0.263 0.186
Web spiders -0.324 -0.524 -0.131 -0.224
Jumping spiders -0.458 -0.059 0.204 0.26
Hunting Spiders 0.429 0.154 -0.234 -0.37
Cyrtorhinus
lividipennis -0.639* -0.849** -0.112 -0.099

Table 51. Effect of weather parameters on pest and predator
population in IPM Field in Kovur – Regression Coefficients
Pest/Predator vs Weather Factors Regression Equation R
2
Jumping spiders (Y) vs Max.
temperature
Y = -31.553 + 0.996X 0.697*
Hunting spiders (Y) vs Max.
temperature
Y = 58.897 – 1.568X 0.720*
Hunting spiders (Y) vs Min.
temperature
Y = 31.936 – 1.099X 0.790*
M. discolor (Y) vs Max. temperature Y = -125.341 + 4.05X 0.582*
M. discolor (Y) vs Min. temperature Y = -61.206 + 3.035X 0.516*
Rove beetle (Y) vs Max. temperature Y = 82.19 – 2.317X 0.631*
Navarai 2002
S. furcifera (Y) vs Min. temperature Y = -918.925 + 34.973X 0.493*
Jumping spiders (Y) vs Rainfall Y = 1.773 + 0.174X 0.798**
S. furcifera (Y) vs Relative humidity Y = -560.418 + 7.346X 0.695**
S. furcifera (Y) vs Rainfall Y = 17.105 + 0.529X 0.846**
S. furcifera (Y) vs Weather factors
1
Y = -180.04 - 6.559X1 + 11.61X2 + 1.654X3 + 0.347X4 0.893*
Oxya spp. (Y) vs Max. temperature Y = 22.768 – 0.603X 0.389*
C. lividipennis (Y) vs Max. temp. Y = 34.783 – 0.966X 0.407*
C. lividipennis (Y) vs Min. temp. Y = 54.341 – 2.089X 0.722**
C. lividipennis (Y) vs Weather factors
1
Y = 99.97 – 0.69X1 - 1.504X2 – 0.459X3 + 0.004X4 0.868**
Sornavari 2002
Samba 2002

Table 52. Correlation coefficients of weather factors vs.
arthropods interaction in rice ecosystem in Kovur
Village (Navarai 2003 )
Total
Rainfall
Nilaparvata
lugens
0.389 0.266 -0.697* 0.14
Sogatella
Navarai 2003
Pest / Natural
enemy
Mean
Max.
Temp.
Mean
Min.
Temp.
Mean
Rel.
Hum.
Sogatella
furcifera
-0.225 -0.298 -0.129 0.192
Nephotettix
virescens
0.197 0.165 -0.534 -0.195
Oxya spp. 0.126 0.158 -0.554 0.526
Web spiders 0.710* 0.633 -0.365 -0.031
Jumping spiders 0.956** 0.909** -0.289 0.111
Hunting spiders 0.061 -0.22 -0.465 -0.435
Micraspis
discolor complex
0.947** 0.932** -0.294 0.182
Earwig 0.893** 0.908** -0.354 -0.078

interaction in rice ecosystem in Kovur Village (Sornavari 2003)
Nilaparvata
lugens -0.357 -0.545 0.606 0.445
Sogatella
furcifera -0.559 -0.364 -0.222 0.496
Nephotettix
Pest / Natural
enemy
Mean
Max.
Mean
Min.
Mean
Rel.
Total
rainfall
Nephotettix
virescens -0.272 -0.212 -0.274 0.643*
Oxya spp. -0.651* -0.567 0.319 0.472
Web spiders -0.308 -0.375 0.342 0.496
Jumping spiders -0.363 -0.5 0.197 0.264
Hunting Spiders -0.562 -0.389 0.071 0.384
Cyrtorhinus
lividipennis -0.629 -0.587 0.365 0.466
Micraspis
discolor complex -0.518 -0.464 0.551 0.048

Table 53. Effect of weather parameters on pest and predator
population in IPM Field in Kovur –Regression Coefficients
Pest/Predator vs Weather Factors Regression Equation R
2
N. lugens (Y) vs Relative humidity Y = 28.731 – 0.369X 0.486*
Web spiders (Y) vs Max. temperature Y = -68.946 + 2.88X 0.504*
Jumping spiders (Y) vs Max. temperature Y = -88.529 + 2.801X 0.913**
Jumping spiders (Y) vs Min. temperature Y = 55.258 + 2.566X 0.826**
Navarai 2003
M. discolor complex (Y) vs Max. temp. Y = -151.588 + 4.757X 0.896**
M. discolor complex (Y) vs Min. temp. Y = -98.647 + 4.506X 0.868**
M. discolor complex (Y) vs weather factors
1
Y = -171.729 + 4.746X1 + 0.274X2 + 0.191X3 + 0.140X4 0.952**
Earwig (Y) vs Max. temperature Y = -65.788 + 2.134X 0.797**
Earwig (Y) vs Min. temperature Y = -43.638 + 2.089X 0.824**
Earwig (Y) vs weather factors
1
Y = -28.635 - 0.188X1 + 2.183X2 – 0.152X3 – 0.140X4 0.877*
N. virescens (Y) vs Rainfall Y = 3.466 + 0.096X 0.413*
Oxya spp. (Y) vs Max. Temperature Y = 36.07 - 0.877X 0.424*
Sornavari 2003
Note:1 - x1, x2, x3 and x4 are maximum temperature, minimum
temperature, relative humidity and rainfall, respectively

Table 54. Correlation coefficient of rice
arthropod fauna in Kovur Village during
Sornavari 2003 - IPM field – Net sweeps
Max. Temp. -0.848** -0.435 0.468 0.133 -0.673* -0.503 -0.484 0.682*
Weather
Parameter
Micraspis
discolor
complex
Parasitic
Hymeno
ptera
Other
Diptera
(Neutrals)
Oxya spp. GLH Thrips Ascid
mites
Bemisia
tabaci
Max. Temp. -0.848** -0.435 0.468 0.133 -0.673* -0.503 -0.484 0.682*
Min. Temp. -0.904** -0.199 0.542 0.257 -0.775* -0.378 -0.235 0.739*
RH 0.451 -0.02 -0.575 -0.324 0.797* 0.396 -0.223 -0.451
Rainfall 0.688* -0.045 -0.348 -0.391 0.24 -0.219 0.172 -0.557

Table 55. Regression coefficients of weather parameters vs.
arthropod population in Kovur Sornavari 2003 Net sweeps
Pest/Predator/ Neutrals vs, Weather Factors Regression Equation R
2
Oxya spp. (Y) vs Max. Temperature Y = 237.973 - 5.919X 0.718**
Oxya spp. (Y) vs Min. Temperature Y = 324.638 – 11.303X 0.818**
Oxya spp. (Y) vs Rainfall Y = 11.787 + 0.345X 0.473*
Oxya spp. (Y) vs Weather factors 0.892*Oxya spp. (Y) vs Weather factors Y = 566.284 + 1.74X1 – 19.867X2 – 1.09X3 – 0.088X4 0.892*
M. discolor complex (Y) vs Max. temperature Y = 144.952 – 3.647X 0.453*
M. discolor complex (Y) vs Min. temperature Y = 213.188 – 7.521X 0.601*
M. discolor complex (Y) vs Relative humidity Y = -83.321 + 1.423X 0.636*
M. discolor complex (Y) vs weather factors Y = 375.199 + 3.654X1 – 18.473X2 + 0.11X3 – 0.302X4 0.886*
Diptera (Neutrals) (Y) vs Max. temperature Y = -1611.441 + 49.489X 0.465*
Diptera (Neutrals) (Y) vs Min. temperature Y = -2374.255 + 95.932X 0.546*

Table 56. Correlation coefficients of mean weather
factors vs. arthropods in rice ecosystem in Kovur
Village (Cumulative of all seasons)
Pest / Natural
enemy
Mean
Max.
Temp.
Mean
Min.
Temp.
Mean
Rel.
Hum.
Total
Rainfall
Nilaparvata lugens 0.235 0.177 -0.054 -0.056
Sogatella furcifera -0.317 -0.068 0.566** 0.725**
Nephotettix
virescens 0.364 0.332 -0.505 0.456virescens 0.364 0.332 -0.505 0.456
Oxya spp. 0.336 0.448 -0.287 0.023
All pests -0.137 0.133 0.306* 0.622**
Web spiders 0.074 -0.012 -0.271 -0.187
Jumping spiders 0.099 0.113 -0.118 -0.011
Hunting Spiders -0.078 -0.097 -0.167 0.034
Cyrtorhinus
lividipennis 0.471 0.368 -0.639* -0.263
Micraspis discolor
complex 0.236 0.223 0.049 -0.418
All predators 0.018 -0.045 -0.249 -0.119

Table 57. Correlation coefficients of extreme weather
factors vs. arthropods in rice ecosystem in Kovur
Village (Cumulative of all seasons)
Pest / Natural
enemy
Highest
Max.
Temp.
Lowest
Min.
Temp.
Highest
Rel.
Hum.
Lowest
Rel.
Hum.
Nilaparvata lugens 0.27 0.189 0.033 -0.081
Sogatella furcifera -0.317 0.149 0.576** 0.525**
Nephotettix
virescens 0.479 0.34 -0.597* -0.416
Oxya spp. 0.267 0.429 -0.242 -0.097
All pests -0.053 0.088 0.399** 0.304*
Web spiders 0.069 0.164 -0.218 -0.265
Jumping spiders 0.123 -0.053 -0.046 -0.152
Hunting spiders -0.027 -0.232 -0.197 -0.127
Cyrtorhinus
lividipennis 0.418 0.401 -0.536* -0.584*
Micraspis discolor
complex 0.215 0.29 -0.15 0.114
All predators 0.028 -0.012 -0.193 -0.235

Fig. 10. Relationship between S. furcifera and relative humidity
(cumulative of all seasons)
y = - 117.59 + 2.208x
120
160
Populationper25hills
y = - 117.59 + 2.208x
R2
= 0.321**
0
40
80
40 50 60 70 80 90 100
Mean Weekly Relative humidity (%)

Fig. 11. Relationship between S. furcifera and Rainfall
(cumulative of all seasons)
y = 23.591+ 0.452x80
120
160
y = 23.591+ 0.452x
R2
= 0.525**
0
40
80
0 50 100 150 200 250 300
Weekly total rainfall (mm.)

Table 58. Regression Coefficients of weather parameters vs.
arthropod populationin Kovur – (Cumulative of all Seasons)
Pest/Predator vs. Weather Factors Regression Equation R
2
S. furcifera (Y) vs Relative humidity Y = -117.591 + 2.208X 0.321**
S. furcifera (Y) vs Rainfall Y = 23.591 + 0.452X 0.525**
1
Y = -368.929 + 4.667X1 + 3.153X2 + 2.175X3 + 0.388X4 0.645**
Mean Weather Factors
S. furcifera (Y) vs Weather factors Y = -368.929 + 4.667X1 + 3.153X2 + 2.175X3 + 0.388X4 0.645**
C. lividipennis (Y) vs Relative humidity Y = 85.194 – 0.936X 0.409*
S. furcifera (Y) vs Highest relative humidity Y = -180.372 + 2.672X 0.332**
S. furcifera (Y) vs Lowest relative humidity Y = -50.385 + 1.488X 0.276**
1
Y = -254.282 – 4.041X1 + 11.881X2 + 0.957X3 +1.306X4 0.535**
N. virescens vs Highest relative humidity Y = 31.275 – 0.272X 0.357*
All pests (Y) vs Highest relative humidity Y = -148.38 + 2.401X 0.159*
C. lividipennis (Y) vs Highest relative humidity Y = 90.614 – 0.88X 0.288*
C. lividipennis (Y) vs Lowest relative humidity Y = 60.672 – 0.696X 0.341*
Extreme Weather Factors

Kalaisekar and Ramamurthy (2004):
The beetle diversity in rice
ecosystems of IARI, New Delhi
was similar in degree between
kharif 2000 and 2001 seasons,
indicating a significant
role of climate on species
diversity.

BPH - optimum temperature for egg
and nymphal development ranged
between 25 and 30oC (Kulshrestha et
al., 1974; Kalode, 1976)
Wet season and relative humidity
favoured WBPH (Tao and Ngoan, 1970;favoured WBPH (Tao and Ngoan, 1970;
Majid et al., 1979),
Rainfall was positively related to GLH
population (Ramakrishnan et al., 1994;
Mallick and Chowdhury, 1999)

High temperature had negative
influence on the egg hatchability
of Hieroglyphus sp. (Dale, 1994).
Lensing et al. (2005) observed that
rainfall had varied impact onrainfall had varied impact on
different groups of spiders, while
lycosids were unaffected;
thomisids and theridiids did not
show clear response but
gnaphosids were affected.

Spatial Distribution
• Brown planthopper and white-backed
planthopper recorded clumped
distribution (ID > 1.64) during 29.17% and
37.04% instances, - all seasons’ data
(irrespective of population level). Clumped
distribution was 71.43% and 63.64%,distribution was 71.43% and 63.64%,
respectively, when observations were
minimum of 1/ hill
• Green leaf hopper (92.59%) and
grasshopper (96.88%) had predominantly
random distribution.

Spatial Distribution
• Maximum clumped distribution
- mirid bug (21.05%) all
seasons’ data (irrespective of
population level) it recorded
100% clumped distribution100% clumped distribution
(when 1/ hill).
• All the other predators were
randomly distributed (>90%).

Table 59. Spatial distribution of rice insects and
spiders in Kovur during Navarai 2002
05-Mar-02 12-Mar-02 20-Mar-02 05-Apr-02 10-Apr-02 17-Apr-02
30 DAP 37 DAP 45 DAP 61 DAP 66 DAP 73 DAP
Pests
Brown planthopper - - 0.96 - - 1.4
White backed planthopper - - - - - 0.96
Green leafhopper - 1.46 0.92 - 0.83 -
Index of Dispersion
Pest / Natural enemy
Green leafhopper - 1.46 0.92 - 0.83 -
Grasshopper - 0.92 0.88 0.96 0.96 0.92
Predators
Web spiders 1.07 1.2 0.84 0.89 1.17 1.17
Jumping spiders 0.96 - - 0.92 1.4 0.83
Hunting spiders 0.9 0.97 0.83 0.92 2.08 0.96
Rove beetle 1.61 1.88 0.96 - - -
M. discolor complex Adult 0.75 - 2.1 0.79 1.13 1.88
M. discolor complex Grub - - 0.92 1.58 0.75 -
Earwig - 0.88 2.08 0.96 - -

Table 60. Spatial distribution of rice insects and
spiders in Kovur during Sornavari 2002
18-Jun-02 25-Jun-02 09-Jul-02 16-Jul-02 23-Jul-02 30-Jul-02 06-Aug-02
25 DAP 32 DAP 46 DAP 53 DAP 60 DAP 67 DAP 74 DAP
Pests
Brown planthopper - 0.96 1.34 0.97 2.87 2.58 1.46
White backed planthopper 1.14 0.77 4 1.77 0.94 1.98 -
Green leafhopper 1.14 0.88 0.96 0.97 1.06 1.61 0.92
Black bug - 2.44 - - - - 0.96
Index of Dispersion
Black bug - 2.44 - - - - 0.96
Grasshopper - 0.92 - 0.96 0.79 0.77 0.92
Predators
Web spiders 1.91 0.73 1.62 0.79 1.29 0.99 1.69
Jumping spiders 0.96 - 0.92 0.79 0.83 0.88 0.89
Hunting spiders 1.05 0.69 0.82 0.97 1.25 0.77 0.97
Mirid bug - - 1.4 1.05 1.36 4.01 1.25
Rove beetle - 0.96 1.61 0.92 - - -
Ground beetle - 0.96 0.96 0.92 0.92 - 0.92
M. discolor Adult 1.14 - - 0.83 0.92 0.88 0.88
M. discolor Grub - - - 0.96 0.92 1.94 -

Table 61. Spatial distribution of rice insects
and spiders in Kovur during Samba 2002
Pests
Brown planthopper - - 0.9 1.14 1.56 1.14 1.58 2.24 1.24 1.25
White backed planthopper 1.48 1.97 1.49 1.37 2.55 0.72 1.56 2.21 0.96 0.92
Green leafhopper - - 0.92 - - 0.96 1.25 0.83 0.83 0.97
Index of Dispersion
19 DAP 26 DAP 33 DAP 40 DAP 48 DAP 82 DAP54 DAP 61 DAP 68 DAP 76 DAP
Black bug - - - 0.92 - - - 0.96 3.05 0.88
Flea beetle 1.14 1.25 1.92 2 0.92 - - - - -
Grasshopper 1.61 0.96 - 0.77 0.79 0.92 0.88 1.4 1.25 1.25
Predators
Web spiders 1.35 1.13 0.54 0.54 0.67 1.05 1.04 1.2 1.03 0.84
Jumping spiders 1.61 0.92 0.96 0.92 0.92 0.92 0.88 0.92 - 0.92
Hunting spiders 0.72 0.64 1.49 0.75 0.71 0.97 0.77 0.72 0.89 0.83
Mirid bug - - - 2 0.83 0.83 1.46 1.34 1.25 0.9
M. discolor complex Adult - 0.96 0.88 - - - 1.4 - 0.96 0.83
Ground beetle 0.96 0.96 1.4 0.88 1.4 0.88 0.96 0.96 - 0.96

and spiders in Kovur during Navarai 2003
17 DAP 24 DAP 31 DAP 38 DAP 45 DAP 53 DAP 59 DAP 66 DAP 73 DAP
Pests
Brown planthopper - - - 1.49 1.75 1.4 0.84 2.44 -
White backed planthopper - 0.83 1.25 - 1.8 2.98 0.95 - -
Index of Dispersion
Green leafhopper - 0.96 - 0.96 0.88 - - - 1.61
Grasshopper - - 0.88 0.96 1.25 0.83 - - 0.88
Predators
Web spiders 0.79 0.76 0.88 1.16 0.83 0.92 0.98 1.53 1.13
Jumping spiders 0.96 - 2 0.92 0.83 0.83 1.21 1.62 1.05
Hunting spiders 0.75 1.35 0.83 0.69 1.03 1.15 1.99 0.77 1.45
M. discolor complex Adult - - - - 0.96 0.97 0.84 1.13 1.15
M. discolor complex Grub - - - - 1.14 0.88 1.42 0.63 0.96
Earwig 1.61 1.61 0.96 1.14 1.14 0.83 0.84 1.46 0.77

and spiders in Kovur during Sornavari 2003
29 DAP 36 DAP 43 DAP 50 DAP 57 DAP 63 DAP 71 DAP
Pests
Brown planthopper 0.96 0.92 1.04 1.49 0.88 3.98 4.63
White backed planthopper 1.05 1.25 0.91 2.71 1.81 1.25 0.92
Green leafhopper 1.58 1.13 0.79 2.11 1.4 0.79 1.83
Index of Dispersion
Grasshopper 0.88 0.92 0.96 1.23 0.83 0.88
Predators
Web spiders 0.94 0.77 0.83 0.91 0.63 1.25 0.89
Jumping spiders 1.4 0.92 0.96 0.96
Hunting spiders 1.05 0.63 1 1.17 0.97 1.07 0.99
Mirid bug 0.96 0.96 1.4 1.79 1.25 2 1.25
M. discolor complex Adult 0.92 0.75 0.9 1.14
M. discolor complex Grub 0.96 0.96 1.76
Ground beetle 0.92 0.88

Table 64. Spatial Distribution of Rice Insects and
Spiders in Kovur (Cumulative of all seasons)
Pest / Predator % Random1
% Clumped1
% Random2
% Clumped2
BPH 70.83 29.17 28.57 71.43
WBPH 62.96 37.04 36.36 63.64
GLH 92.59 7.41 - -
Black bug 57.14 42.86 - -
Flea beetle 60 40 - -
Grasshopper 96.88 3.13 - -
Pests
Grasshopper 96.88 3.13 - -
Web spiders 95 5 93.33 6.67
Jumping spiders 96.77 3.23 - -
Hunting spiders 94.87 5.13 100 0
Mirid 78.95 21.05 0 100
Micraspis discolor
complex Adult 92 8 100 0
M. discolor
complex Grub 90.91 9.09
- -
Ground beetle 100 0 - -
Earwig 91.67 8.33 - -
Predators

Random distribution observed in the
case of immigrant adults of BPH
(Hoppe, 1973; Kalode, 1976) as well as
during the early stage of the crop, but
clumped afterwards (Chen, 1976; Otake
and Hokyo, 1976; Dyck et al., 1979;
Kamal et al., 1995).Kamal et al., 1995).
Kamal et al. (1995) observed the change
in the spatial pattern from random to
clumped distribution as crop growth
progressed in the case of other
arthropods such as GLH, mirid bug,
carabids and ladybird beetles

Dale (1994) reported that distribution
pattern of BPH and WBPH was different
with BPH following a clumped pattern
while it was not so in the case of WBPH.
However, Zhou et al. (2003) observed
WBPH to follow clumped distribution
even under low density.
Distribution pattern of the predators
particularly spiders corresponded with
their prey, viz., planthoppers (Ye et al.,
1982; Wang and Yan, 1989)

ECOLOGICAL SUCCESSION OF

Fig. 14. Ecological succession of Rice insect pests in
Kovur Village during Sornavari 2002
Vegetative Stage Reproductive Stage Ripening Stage
Brown planthopper
White backed
planthopper
Green leaf hopper
White leaf hopper
Zigzag leaf hopper
Black bug
Orange bugOrange bug
Leaf folder
Stem borer
Skipper
Yellow hairy caterpillar
Cutworm
Grasshopper
Hispa
Flea beetle
11 DAP 18 DAP 25 DAP 32 DAP 46 DAP 53 DAP 60 DAP 67 DAP 74 DAP 81 DAP

Fig. 15. Ecological succession of Rice Predatory
fauna in Kovur Village during Sornavari 2002
Vegetative Stage Reproductive Stage Ripening Stage
Web spider
Jumping spider
Hunting spider
Mirid bugMirid bug
Rove beetle
Ophionea indica
Micraspis discolor complex Adult
M. discolor complex Grub
M. discolor complex Pupa
S hoffmani
Earwig
Assassin bug
Preying mantis
11 DAP 18 DAP 25 DAP 32 DAP 46 DAP 53 DAP 60 DAP 67 DAP 74 DAP 81 DAP

Sornavari and Samba seasons - 2 &
3 distinct peaks, respectively.
Maximum peak - ripening stage .
Brown Planthopper
Maximum peak - ripening stage .
Two major peaks per year (July-
August & late November).

Fig. 22. Seasonal fluctuation of Brown planthopper
during different seasons
15
20
25
30
Populationper5hills
0
5
10
15
1 2 3 4 5 6 7 8 9 10 11 12
Weeks after planting
Populationper5hills
Navarai 2003 Sornavari 2003

Fig. 23. Seasonal occurrence of Brown planthopper in a rice field in Kovur (2002-03)
15
20
25
30
Populationper5hills
Jul 30
Aug 5
0
5
10
Populationper5hills
Navarai 2002 Sornavari 2002 Samba 2002 Navarai 2003 Sornavari 2003
Nov 26

1 to 2 peaks - Sornavari and Samba
seasons.
Peak population - reproductive stage
White-backed planthopper
Peak population - reproductive stage
Two major peaks/ year (early to mid
July & early November)

Fig. 24. Seasonal fluctuation of White-backed
planthopper during different seasons
20
25
30
35
Populationper5hills
0
5
10
15
1 2 3 4 5 6 7 8 9 10 11 12
Populationper5hills
Sornavari 2002 Samba 2002 Navarai 2003 Sornavari 2003

Fig. 25. Seasonal occurrence of White-backed planthopper in a rice field in Kovur
(2002-03)
20
25
30
35
Populationper5hills
Jul 9
Nov 6
0
5
10
15
20
Populationper5hills
Jul 15

Reproductive stage supported
maximum peak population during
Navarai 2002, Sornavari 2003
seasons except Sornavari 2002
Green leaf hopper
seasons except Sornavari 2002
season - ripening stage.
Major peaks - mid-March & mid
to late July.

Fig. 26. Seasonal fluctuation of Green leaf hopper
2
3
3
4
4
Populationper5hills
0
1
1
2
1 2 3 4 5 6 7 8 9 10 11 12
Populationper5hills

Fig. 27. Seasonal occurrence of Green leaf hopper in a rice field in Kovur (2002-03)
2
2.5
3
3.5
4
Populationper5hills
Mar 12
Jul 23
Jul 15
0
0.5
1
1.5
Populationper5hills

Samba 2002 and Sornavari 2003 -
peaks during reproductive stage;
Sornavari 2002 season: peak -
Oxya spp.
Sornavari 2002 season: peak -
ripening stage.
2 major peaks/ year (mid to end of
July and end of October.

Fig. 28. Seasonal fluctuation of Oxya spp. during
different seasons
2
3
Populationper5hills
0
1
1 2 3 4 5 6 7 8 9 10 11 12
Populationper5hills

Fig. 29. Seasonal occurrence of Oxya spp. in a rice field in Kovur (2002-03)
1.5
2
2.5
Populationper5hills
Jul 30
Oct 29 Jul 15
0
0.5
1
Populationper5hills

3 peaks/season except Sornavari
2002. Highest peak - ripening stage
except Navarai 2002 (reproductive
Spiders
except Navarai 2002 (reproductive
stage).
2 major peaks/year (mid March to
early April & late July to early
August).

Fig. 30. Seasonal fluctuation of Spiders
15
20
25
Populationper5hills
0
5
10
1 2 3 4 5 6 7 8 9 10 11 12
Populationper5hills

Fig. 31. Seasonal occurrence of Spiders in a rice field in Kovur (2002-03)
15
20
25
Populationper5hills
Mar 12
Jul 23
Apr 8 Aug 5
0
5
10
Populationper5hills

2 peaks during Sornavari
seasons, but one peak during
Samba.
Cyrtorhinus lividipennis
Samba.
Maximum peak occurred mostly
during ripening stage. 1 major
peak/year (July).

Fig. 32. Seasonal fluctuation of C. lividipennis
6
8
10
12
14
Populationper5hills
0
2
4
6
1 2 3 4 5 6 7 8 9 10 11 12
Populationper5hills
Sornavari 2002 Samba 2002 Sornavari 2003

Fig. 33. Seasonal occurrence of C.lividipennisin a rice field in Kovur (2002-03)
8
10
12
14
Populationper5hills
Jul 30
0
2
4
6
Populationper5hills
Jul 15

1 peak in the crop growth period
except Navarai 2002 (2 peaks).
Maximum peak - ripening stage
Micraspis discolor
Maximum peak - ripening stage
in all 3 seasons.
2 major peaks/year (early April &
end July).

Fig. 34. Seasonal fluctuation of M. discolor during
different seasons
3
4
5
6
Populationper5hills
0
1
2
1 2 3 4 5 6 7 8 9 10 11
Populationper5hills
Navarai 2002 Navarai 2003 Sornavari 2003

Fig. 35. Seasonal occurrence of M. discolor in IPM field in Kovur (2002-03)
4
5
6
Populationper5hills
Apr 10
Apr 8 Jul 28
0
1
2
3
Populationper5hills
Jul 30

ECOLOGICAL SUCCESSION
• Spiders were the first to colonize wetland
rice In Philippines (Reddy and Heong (199)
• S. geminata flourished within fields, not
only during the crop season, but also
throughout the dry season fallows &throughout the dry season fallows &
aggressively predatory (Way et al., 2002).
• In Vadodara dt., Gujarat, maximum
population of spiders was collected from
rice fields during September than other
months (Kumar and Shivakumar, 2005).

• The fauna recorded from the rice
field were observed to follow an
uniform pattern of seasonal
ECOLOGICAL SUCCESSION
uniform pattern of seasonal
colonization and succession
during successive rice
cultivation cycles (Bambaradeniya et
al., 2004).

PREY- PREDATOR RELATIONSHIP
AMONG IMPORTANT ARTHROPODS

Table 72. Prey-predator relationship in IPM and non-IPM fields
during different seasons – Correlation coefficients
WhiteLH
Chrysomelid
BPH
GLH
BPH
WBPH
GLH
BPH
GLH
BPH
WBPH
BPH
Web spiders 0.751
a
0.560
a
0.912** 0.667* 0.983** 0.508 0.42 0.036 0.669* 0.209 0.086 0.748*
Jumping spiders -0.553
a
-0.711
a
0.202 0.187 0.61 0.776* -0.063 0.372 0.158 0.432 0.788** -0.018
Sornavari
2003 IPM
Samba 2002
IPM
Samba 2002
Non-IPM
Sornavari 2002
IPM
Sornavari 2002
Non-IPM
Predator/ Prey
Navarai 2002
IPM
Hunting spiders 0.102
a
0.860
a
* 0.55 0.612 0.628 0.396 0.805* -0.175 0.057 0.125 0.225 0.399
C. lividipennis - - 0.825** 0.092 0.369 0.747 0.343 0.730** 0.826** 0.162 -0.095 0.348
Rove beetle -0.308b
0.733b
* - - - - - - - - - -
M . discolor complex 0.438b
- - - - - - - - -0.142 -0.3 0.482
Ophionea indica - - - - - - - - - 0.53 0.817** -
Ear wig 0.715b
* 0.220b
- - - - - - - - - -
Other predators 0.167b
0.667b
0.750* 0.53 -0.181 0.441 -0.216 0.311 0.706* 0.699* 0.389 0.821**
a Significance of r = 0.811 (5 %) and 0.917 (1 %) for 4 df; b Significance of r =
0.707 (5 %) and 0.834 (1 %) for 6 df. In other seasons the df did not
change; * significant at 5%; ** significant at 1%

Table 73. Prey and Predator Relationships in IPM Field
in Kovur – Regression Coefficients
Prey – Predator Regression Equation R
2
C. spectra (Y) vs Earwig Y = 0.311 + 0.634X 0.511*
Chrysomelid beetle (Y) vs Hunting spiders Y = -0.844 + 0.469X 0.740*
Chrysomelid beetle (Y) vs Rove beetle Y = 0.846 + 0.183X 0.537*
N. lugens (Y) vs Predators
1
Y = 0.088 + 0.782X1 + 1.13X2 + 0.556X3 + 1.127X4 – 2.8X5 0.977**
N. lugens (Y) vs Web spiders Y = -8.498 + 0.903X 0.832**
N. lugens (Y) vs C. lividipennis Y = 8.795 + 1.303X 0.681**
Navarai 2002
Sornavari 2002
N. virescens (Y) vs Web spiders Y = 0.937 + 0.09X 0.445*
N. virescens (Y) vs Web spiders Y = -0.706 + 0.255X 0.447*
N. virescens (Y) vs C. lividipennis Y = 0.499 + 0.423X 0.682**
N. lugens (Y) vs Web spiders Y = -24.105 + 2.796X 0.559*
N. lugens (Y) vs Other predators
2 Y = -12.811 + 6.12X 0.674**
S. furcifera (Y) vs C. lividipennis Y = 3.224 + 0.845X 0.430*
Sornavari 2003
Samba 2002
Note: 1 x1, x2, x3, x4 and x5 are web spiders, jumping spiders, hunting spiders, C. lividipennis and other
predators, respectively 2 Other predators include brown mirid bug, M. discolor complex, S. hoffmani,
reduviid bug, O. indica, black carabid, earwig, rove beetle, long-horned grasshopper, and ants.

Table 74. Prey and Predator Relationships in non-
IPM Field in Kovur – Regression Coefficients
Prey - Predator Regression Equation R
2
Sornavari 2002
S. furcifera (Y) vs Jumping spiders Y = -19.931 + 24.776X 0.603*
N. virescens (Y) vs Hunting spiders Y = -1.438 + 0.735X 0.647*
S. furcifera (Y) vs Jumping spiders Y = 10.956 + 41.281X 0.621**
S. furcifera (Y) vs O. indica Y = -13.737 + 46.605X 0.668**
Samba 2002

Table 75. Prey-predator relationship in IPM
field (Cumulative of all seasons) –
Correlation coefficients
Interacting Pest/Predator BPH WBPH GLH
Web spiders 0.506** -0.018 0.371*
Jumping spiders 0.036 -0.043 -0.044
Hunting spiders 0.284 -0.013 0.378**
C. lividipennis 0.636** 0.135 0.299*
Web spiders + C. lividipennis 0.635** 0.042 0.397**
Jumping spiders + C. lividipennis 0.614** 0.117 0.272
Hunting spiders + C. lividipennis 0.627** 0.093 0.429**
Significance of r = 0.288 (5%) and 0.372 (1%) at 45 df.

Fig. 36. Prey - predator relationship between
N. lugens and web spiders
y = - 2.706 + 0.656x
80
100
120
140
populationper25hills
y = - 2.706 + 0.656x
R2
= 0.256**
0
20
40
60
0 20 40 60 80 100
Web spiders population per 25 hills
N.lugenspopulationper25hills

Fig. 37. Prey - predator relationship between
N. lugens and C. lividipennis
100
120
140
populationper25hills
y = 5.111 + 1.49x
R2
= 0.405**
0
20
40
60
80
0 20 40 60 80
C. lividipennis population per 25 hills
N.lugenspopulationper25hills

Table 76. Prey and Predator Relationships in IPM Field in Kovur
(Cumulative of all Seasons)- Linear Regression
Prey - Predator Regression Equation R2
N. lugens (Y) vs Web spiders + C. lividipennis Y = -4.456 + 0.609X 0.403**
N. lugens (Y) vs Jumping spiders + C. lividipennis Y = 0.999 + 1.365X 0.377**
N. lugens (Y) vs Hunting spiders + C. lividipennis Y = -6.253 + 1.085X 0.393**
N. lugens (Y) vs Predators1
Y = -5.832 + 0.368X - 0.446X + 0.53X + 1.117X – 0.041X 0.489**
Note:1 - x1, x2, x3, x4 and x5 are web spiders, jumping spiders,
hunting spiders, C. lividipennis and other predators, respectively
* significant at 5%; ** significant at 1%
N. lugens (Y) vs Predators1
Y = -5.832 + 0.368X1- 0.446X2 + 0.53X3 + 1.117X4 – 0.041X5 0.489**
N. virescens (Y) vs Web spiders Y = 1.671 + 0.081X 0.138*
N. virescens (Y) vs Hunting spiders Y = 1.041 + 0.201X 0.143*
N. virescens (Y) vs C. lividipennis Y = 2.946 + 0.118X 0.089*
N. virescens (Y) vs Web spiders + C. lividipennis Y = 1.755 + 0.064X 0.157*
N. virescens (Y) vs Hunting spiders + C. lividipennis Y = 1.430 + 0.124X 0.182*
N. virescens (Y) vs Predators1
Y = 0.121 + 0.087X1- 0.033X2 + 0.2X3 + 0.031X4 – 0.084X5 0.304**

PREY- PREDATOR RELATIONSHIP
• LONG TERM ECOLOGICAL
STUDIES in rice fields in Thailand:
• Importance of combined activity of
many different natural enemies, and
also that of non-specific predators
& parasitoids.& parasitoids.
• Predators such as Odonata &
spiders were essential for the
control of some adult pests, & were
maintained on chironomids in the
absence of pests (Yasumatsu, 1983)

Correlation Frequency
• Between population density of
spider sub-community & BPH for 11
years, & found it to be +0.64 in
China (Liu et al. 2002)
• Spider population exhibited• Spider population exhibited
significant + correlation with WBPH
population, whereas rove beetles
showed significant + correlation
with leaf folder infestation in New
Delhi (Chander & Singh, 2003)

• Predatory habits may vary from those with
a wide prey range as in the case of
spiders, rove beetles, earwigs and
carabids to that with narrow prey range as
in the case of mirids and ladybirds
(Reissig et al., 1986; Heong et al., 1991;
Settle et al., 1996).Settle et al., 1996).
• Application of insecticide in the non-IPM
field substantially affected their
relationship. Such detrimental effects of
insecticides have been already reported
(Kenmore et al., 1984; Ooi, 1986).

Species composition: 11 villages, 4
districts
INSECTS: 313 taxa; 110 families & 15
orders,
SPIDERS: 61 taxa; 16 families, &
MITES: 5 taxa; 3 suborders & 5 families.MITES: 5 taxa; 3 suborders & 5 families.
Biodiversity indices: α & β diversity
Richness; Diversity; Evenness;
Rarefraction
Similarity indices: Jaccard index;
Sorensen index

Influence of agronomic practices on
biodiversity
Population dynamics – Visual count,
Netsweeps; Nursery & main field
Effect of weather factors on
important arthropods: Individualimportant arthropods: Individual
seasons, all five seasons; mean
WF & extreme WF
Spatial distribution
Ecological succession
Prey- predator relationship

• Validation of data on a larger scale in
different rice ecosystems (Tankfed, delta
& well irrigated)
• To enhance entomophage diversity for
natural pest management
• To develop methods for the conservation
and enhancement of most promisingand enhancement of most promising
predatory and parasitoid fauna
• To undertake biosystematic and
taxonomic studies on the important
groups of arthropods
• To bring out a monograph on arthropods
in rice ecosystem

Thank youThank youThank youThank you
Cteniopus sulphureus

Ecology and biodiversity of agriculturally important rice field arthropods

Recomendados

Recomendados

Más contenido relacionado

La actualidad más candente

La actualidad más candente (20)

Similar a Ecology and biodiversity of agriculturally important rice field arthropods

Similar a Ecology and biodiversity of agriculturally important rice field arthropods (20)

Más de Diraviam Jayaraj

Más de Diraviam Jayaraj (14)

Último

Último (20)

Ecology and biodiversity of agriculturally important rice field arthropods