Rice lecture final

Production Technology of
Rice
by
Hafiz Ali Bashir

Origin, History and Importance
 Rice is cultivated and eaten mostly in the “rice bowl” region,
which consists of Asia and middle/near east countries. Juliano
1985:15
IRC 2003:154888

Rice has been cultivated in these regions for over nine
thousand years, which means that it is highly variable and
adaptable. Its been grown in the lowlands of India to as
high as three thousand meters in Nepal. Lang 1996:5
IRC 2003:18437

Native to the deltas of the great Asian rivers
 the Chang (Yangtze),
Tigris,
 Euphrates.
Ganges,

 First domesticated in,
 Eastern Himalayas (i.e. north-eastern India),
 Burma,
 Thailand,
 Laos,
 Vietnam and
 Southern China.
 southern China

In the sub-continent found in the north and
west in 2000 BC.
Perennial wild rice still grow in Assam and
Nepal.
In southern India it appeared 1400 BC after its
domestication in the northern plains.

 Consumed by 5.6 billion people world wide.
World consumption is highest in Asian
countries.
Rice industry is an important source of
employment and income for rural people.
Provides 21% per capita energy.

15% of per capita protein.
Seventy percent of daily calories.
Provides minerals, vitamins, fiber, vitamin A,
zinc and iron.

Rice exporting countries
Sr. No Countries Export
1 Thailand 10 million tons (34.5% of
global rice exports)
2 India 4.8 million tons (16.5%)
3 Vietnam 4.1 million tons (14.1%)
4 Myanmar 3.314 million tons (11.0%)
5 United States 3.1 million tons (10.6%)
6 China 901,550 tons (3.1%)
7 Egypt 836,940 tons (2.9%)
8 Italy 668,940 tons (2.3%)

Rice cultivation in Pakistan
Pakistan’s annual production is more than 4.57
million tons and area 2.21 m.ha.
Kollar track of rice consists of Gujranwala,
Lahore, Sialkot, Shakhupura, Hafizabad.
Third largest crop after wheat and cotton.
 Second staple food of pakistan .

Annual local consumption crosses 2.5 million
tons.
Contributes about 1.6 percent to the
country’s gross domestic product
The per acre yield is 26 to 27 mounds.

Rice production in Punjab
• Area (thousand acre) thousand hactare
Year Bsmati
Fine rice
IRRI
coarse rice
2006-07 1474.24 (3643) 138.81 (343)
2007-08 1377.12 (3403) 159.85 (395)
2008-09 1548.30 (3826) 202.34 (500)
2009-10 1413.95(3494) 218.93 (541)
2010-2011 1313.59 (3248) 174.27 (443)

Production of rice in punjab (1000
metric tonne)
Year Basmati IRRI
2006-07 2493.63 334.41
2007-08 2453.15 414.37
2008-09 2601.65 517.66
2009-10 2475.43 532.15
2010-11 2323.43 435.15

Botanical classification
Botanical Name : Oryza sativa L.
Family : Gramineae/ Poaceae
Kingdom: Plantae
Division: Magnoliophyta
Class: Liliopsida
Order: Poales
Genus: Oryza
Species Sativa

Rice plant is an annual,
2 to 6 ft (61–183 cm) tall,
round, jointed stem,
 long, pointed leaves,
edible seeds borne in a dense head on
separate stalks.
Long day plant
Self pollinated

Growth stages of rice
Germination
Seedling growth
Tillering
Stem elongation
Booting
Inflorescence
Anthesis

Milk development
Dough development
Ripening

Factors responsible for rice yield
Selection and preparation of soil
Selection of approved varieties
Seed rate
Sowing and transplantation of nursery
Irrigation on proper time
Proper use of fertilizers
Weeds management
Important diseases of rice and their control

Harmful insects and their control
Harvesting at proper time

Rice varieties
provinces Fine varieties Coarse varieties
Punjab Super Basmati, Basmati
2000, Basmati Pak (karnal
Basmati), Basmati 370,
Basmati 515
KSK 282, NIAB IRRI 9, KSK
133
Sind Shadasb, Khushboo, Sada
Hayat,
Kinoo 92, DR-82, DR 83,
DR-92
KPK JP-5, Basmati 385, Sawat-1, Sawat-2, IRRI-6,
KS-282, Fakhar Malakand
Balochistan Basmati-386 IRRI-6 DR-83 KS-282,

Soil
Can be grown in type of soil exept sandy soil.
Can be grown on salt effected soil where
other crops can not be grown successfully.
Clay Loam soil with optimum quantity of
organic matter and more water holding
capacity is best for rice cultivation.

Climate
Can be grown under variety of climate,
tropical regions
cooler regions
temperate regions.
humid climate.
Best suited to regions, which have high
humidity, prolong sunshine and an assured
supply of water.

Rice Nursery and Early Crop Management

Seed Rate for nursery (kg/acre)
Sr. No Rice varieties Wet
method
Dry
method
Rabi
method
1 IRRI 6,KSK 282,
KSK 133
6-7 8-10 12-15
2 Supper Basmati,
Basmati 385,
Basmati 2000,
4.5-5 6-7 10-12

Sowing and transplanting time of
nursery
Sr. No Rice varieties Sowing time Transplan
ting time
1
IRRI 6,KSK 282, KSK 133 20 May to 7
June
20 June 7
July
2
Supper Basmati,
Basmati 385,
Basmati 2000,
20 May to
20 June
20 May
to 20 July

Seed dressing
Seed dressing is done to control diseases e.g,
Blast
Bakanae
Stem rot
It is done by soaking the seed into water
contain fungicide 2.5 g/ L water

What is the goal of Crop Establishment?What is the goal of Crop Establishment?
 To secure a uniform plant
population that can produce high yields

Methods of sowing nursary
WET BED
Irrigate, plow, puddle and level the field
Prepare beds of 1 to 1.5 m width, 4-5 cm
height & any convenient length
Start preparing the seedbed 2 weeks before
planting time
Seedlings are ready for transplanting in 25-35
days.

Water the seedbed 2-3 DAS .
Maintain a water level of 2-5 cm, depending
on the height of seedlings
Apply 20-40 g urea or DAP per m2
at 10 DAS, if
needed

Wet-bed Rice NurseryWet-bed Rice Nursery

• DRY BED method
Bed is prepared in dry conditions
Water the seedbed till saturation after sowing
Then water the plots periodically as seedlings
emerge & grow
This method is practiced in areas where soils
are loamy or silt loam.
Puddling is not possible.

Dry-bed Rice NurseryDry-bed Rice Nursery

Rabi method of nursery sowing
Practiced in D.G. khan
Areas where soil is hard
Uprooting of nursery is not possible
Nursery plots are leveled
Crop residue spread then burnt

Para shoot rice nursery: What are the: What are the
limitations?limitations?
Farmers have to buy plastic trays
Heavy rains just after SB may disturb the
distribution of broadcasted seedlings
IRRI: Rice Production Course

TransplantingTransplanting::
Most common methodMost common method
in small farms of Asiain small farms of Asia

TRANSPLANTING OF RICE
IRC 2003:1914

Transplanting: Critical FactorsTransplanting: Critical Factors
• Proper nursery management
• Careful handling of young seedlings for fast revival
and early growth after TP
• Shallow transplanting at 1-2 cm depth
• Optimum plant-to-plant spacing: 20 x 20 cm to 25 x
25 cm
• Optimum number of seedlings: 1-2 hill-1

TP: Careful Handling ofTP: Careful Handling of
SeedlingsSeedlings

Manual Transplanting: whatManual Transplanting: what
are the advantages?are the advantages?
 Good head start for
plant growth over
weeds
 Shorter duration in
main field
 Easy to maintain
uniform plant spacing
& population, if
planted in rows

Manual TP: What are theManual TP: What are the
constraints?constraints?
 Tedious & labor
intensive, > 30 PD ha-1
 Difficult to find
labor to plant on time
 Drudgery & back
problem
 Poor plant population due to contract TP
on area basis

Manual PlanterManual Planter

 Chinese planter
 Japanese planter

Para shoot rice nursery
transplanting-manually

Source: Dr. Sumith, RRDI,
Para shoot rice nursery
transplanting-manually

Para shoot rice nursery transplanting with
Machine

Para shoot nursery : What are thePara shoot nursery : What are the
advantagesadvantages
Low seed rate: 15-20 kg ha-1
Less labor for CE (16 for SB vs. 30-36 for TP)
No bird damage in the nursery and main
field
Early crop maturity by 7-8 days
Water saving: 10 irrigations for SBR vs. 12
for TPR

Less use of agro-chemicals as they can be
applied directly to the nursery

Advantages & Disadvantages
 The young rice plant is raised
in a small seed bed, so it can
receive intensive care and
protection
 The field can be used to grow
other thing according to the
time taken to grow the rice.
 Increase of crop collected per
unit area because the caring of
the farm will be held
intensively.
 Need a lot of water to grow
crop
 Need to take care
 Weak to pesticides
Advantages Disadvantages

Direct Seeding of Rice: Why?Direct Seeding of Rice: Why?
• To reduce labor input
• To tackle labor shortage &
high wages
• To establish crops on time
• To maintain optimum
plant population

Direct Seeding of Rice: IncentivesDirect Seeding of Rice: Incentives
 Increasing water crisis is forcing farmers
and researchers to find out ways to
decrease water use in rice production.
 In Asia, irrigated agriculture accounts
for 90% of total diverted freshwater, and
more than 50% of this is required to
irrigate rice.

 Direct seeding offers a promising solution
for this by saving water and labor
 Direct seeding is a potential alternative to
the traditional production system
 Reduced cost: US$ 60-80 per ha
 Less methane emission: DDS < WDS < TP

Direct Seeding RequirementsDirect Seeding Requirements
• Good Land Prepration &
leveling
• Furrows to drain water
• Saturated soil (WDS) &
moist soil (DDS) for first
7-10 days

• Varieties: early seedling vigor, fast canopy
dev., non-lodging
• Quality seed
• Effective weed control: cultural, mechanical,
herbicides

Level field for DDS Level field for WDS
Well-prepared and Leveled
Fields for Direct Seeding

Direct Seeding MethodsDirect Seeding Methods
• Wet direct seeding (WDS): puddled soil,
broadcast- or row-seeded
> Surface WDS
> Subsurface WDS
> Water seeding
• Dry direct seeding (DDS): dry/moist soil,
broadcast or drilled in rows

Drum seeder,
8 kg wt + 12 kg seed

Drum seeder
Seed hoppers
Seed holes

Dry SeedingDry Seeding
 Used in rainfed areas
 Dry seed
 Seed rate 75 kg ha-1
 Germination with rainfall;
drought
 High pest incidence
Seeding behind Machine seeding
Dry broadcasting

TPR-B: TransplantingTPR-B: Transplanting
seedlings on bedseedlings on bed
•Good CE, but more labor
• Good plant growth & uniform tillering
•High yield as that of TPR
• Less water use (by 20-30%) than that of
TPR

DSR-B: Dry drill seeding on bedsDSR-B: Dry drill seeding on beds
• Fast & efficient seeding, but poor CE
• May need saturated soil for the first 25-30
days
• Micro-nutrient deficiency: Fe, Zn, Cu, etc.
• Severe weed infestation, needs effective
herbicides
•Termite problems
•Saving in water (~ 20-30%)
• Conserves rain water & avoids flooding

Water management
Judicious use of water is necessary
At transplanting and one week after depth of
water 3-4 cm
Higher water depth is harmful
Lower water depth cause drying
Seven days after transplanting depth of water
should be 8 cm
Water should remain standing in field
continuously for 25-30 days.

Fertilizer managment
Adequate and timely application of fertilizers is
essential
Soil analysis should be done
Incorporation of green manure crop before
transplanting to increase organic matter
All of P and k and half of the N is incorporated
into soil at the last ploughing
Remaining N is top dressed after 30-35 days

Quantity of fertilizer (kgacre)
Type of
varieties
N P K Amount of
fertilizer at
the time of
puddling
After
transpla
-nting
IRRI-6, KSK
282, Niab IRR-
9, KSK 133
69 41 32 1.5 Bag
Urea+4.5 Bag
SSP+1.25 Bag
Potassium
Sulphate
1.5 Bag
of urea
after 30-
35 days of
urea
transplant
ing
Super
Basmati,
57 32 25 1 Bag
Urea+3.5 Bag
0.5 Bag
of urea

Weeds management
15%-20% losses due to weeds
Some time up to 50%
Three groups of weeds in rice
Weeds of grass family
Weeds of sedge family
Broad leaf weeds

Weeds of grass family
Swanky grass (Echinochloa colon)
Dhedan ( Echinochloa crusgalli)
Khabal grass (Cynodon dactylon)
Narro (Paspalum distichum)

Weeds of sedge family
Ghoein (Cyperus difformus)
Bhoein (Cyperus iria)
Deela (Cyperus rotundus)

Broad leaf weeds
Mirch boti (Sphenoclea zeylanica)
Chopti (Marsilea minuta)
Darai boti (Fclipta bprostata)

Swanky grass (Echinochloa colon)

Common Name:
Bermudagrass
Scientific Name: Cynodon
dactylon mudagrass

Mirch boti (Sphenoclea zeylanica)

INTEGRATED WEED MANAGEMENT (IWM)
IWM is aimed to reduce weed
population to the level at which there
would be no economical losses of crop.
Effective IWM combines preventive,
cultural, mechanical and biological weed
management methods in an effective,
economical and ecologically safe
manner.

weed management technologies can
optimize rice production.
Holistic multi-disciplinary integrated
approach is necessary.
combination of various weed management
methods together is called integrated
weed management (IWM).

• Weeds are allowed to emerge and are
then killed during tillage operations.
• First weeding should be done between
15 to 21 days after germination. Second
weeding is done 30 to 45 days after first
weeding.

Application of mulch reduces weed growth
and conserve moisture and fertilizers.
 Use of weed free seed material is
recommended for better weed
management.

Maintaining 5–7 cm water depth and
avoiding drainage prevents germination
of weed seeds.
 Azolla can suppress the weed growth
by reducing sunlight and aeration.
 Herbicide should be applied when
there is a thin film of water in the field

 Application of pendimethalin 1.0kg/ha on
5 days after sowing
 Pretilachlor + Safener (Sofit) 0.45kg/ha
on the day of receipt of soaking rain
followed by one hand weeding on 30 to 35
days after sowing effectively controls
weeds in kharif season.

Advantages of Weed
Control
Increase in yield
Conservation of soil moisture
 through reduced competition for
 sunlight, nutrients and water.
Reduced incidences of pest and disease

Dark-headed stem borer (Chilo polychrysus)
Larva
• Neonate - grayish white with a large head.
• Head and prothoracic shield are black.
• Body dirty white with five longitudinal stripes
of grayish violet or purplish brown situated
mid- dorsally, latero-dorsally, and laterally.
Adult
• Adults brownish yellow.
• The center of the forewings has dark
markings of silvery scales or 6-7 tiny black
dots.
• The hind wing has a lighter color.

• Larva
The larva is whitish to light yellow. A
full-grown larva is 25 mm long. The
larva has no body marks.
• Pupa
The fresh pupa is soft-bodied and
whitish. It grows up to 25 mm in
length. With age, it turns brown.
• Adult
The male and female adults are
immaculately white in appearance.
They have a tuft of long hairs on the
thorax. The male is smaller than the
female.
White stem borer (Scirpophaga innotata)

Yellow stem borer : Scirpophaga incertulas (Walker)
 Most destructive pest.
 Attack all stages of the rice plant
 1% to 19% yield loss in early planted rice crops and
 38% to 80% yield loss in late-planted rice.
 Low infestations by stem borers may not result in yield loss
because of plant compensation.
 Sprays for stem borer control carried out when whiteheads are
visible will not result in any economic gain.

Adult
 The female is whitish to yellowish.
 Has a pair of clear black spots at the middle
of each forewing.
 The male is smaller and dull in color. It has
two rows of black spots at the tip of the
forewings.
 The male’s wingspan is about 20-30 mm,
whereas the female’s is 24-36 mm.
 The female’s abdomen is wide with tufts of
yellowish hairs all over. The male has a
slender abdomen toward its anal end and is
covered with thin hairs dorsally.

Egg
Individual eggs are white,
oval, flattened, and
covered with brownish
hairs from the anal tufts
of the female.
Larva
The larval body is
yellowish green.
The head and
prothoracic shield of a
full-grown larva are
brown. The larva passes
through six instars. The
first instar is about 1.5
mm long and the last
instar 20 mm long.
Pupa
The pupa is pale green. It is about 12
mm long and 3 mm wide. The pupa is
enclosed in a white silk cocoon. When
newly formed, the cocoon is pale
brown. It gradually turns dark brown.

 Adult
 The forewings are bright pale brown
with some scattered dark brown
markings.
 A purplish red band radiates from the
central point in the forewing to the wing
tip.
 Light stripes border the wing apex.
 The hind wings are whitish with light
yellow scales along the major veins.
Pink stem borer Sesamia inferens

 Larva
 Newly hatched larvae are white with a yellowish tinge and
a black head capsule.
 Mature larvae turn pinkish purple with a brown or
orange-red head capsule.
 The body has no longitudinal stripes.
 Measures 25.0 to 35.0 mm long and 3.0 mm wide.
 Pupa
The pupa is brown to dark
brown with a tinge of
bluish powdery substance.

 Adult
 The adults are brownish
yellow with silvery scales
 A row of 7 or 8 small black
dots at the terminal margin of
each forewing.
 The forewings are darker than
the hindwings.
Striped stem borer : Chilo suppressalis
Egg

 Larva
 Neonate larvae have a large head.
 Head and prothracic shields are shiny
brown or orange.
 Body is light brown or pink with five rows of
longitudinal stripes, which run the entire
length of the body.
 The stripes are brown or pale purple,
situated dorsally and laterally.
 The full-grown larvae measure 20 to 25
mm long.
 Pupa
 The pupa is reddish brown.
 It measures about 11 to 13.5 mm long.
 Several spines are prominent on the last
segment of the pupa.

 Common in rice ecosystems.
 Infests at the early crop stages.
 Population densities are usually insufficient to cause
significant losses in yield. Crops generally recover
from this damage.
 Insecticide use have little or no economic returns.
Rice leaf folder : Cnaphalocrocis medinalis

Egg
The newly laid egg is jelly-like and
transparent. It is oblong with an
irregular upper surface. The
mature egg is ovoid and whitish
yellow. It is ventrally flattened.
Larva
Neonate larvae are yellow. With age,
they turn yellowish green with brown
heads. They have distinct pinnaculae or
one pair of subdorsal spots on the
mesonotum. The apex of their pronotum
is always straight. They are from 12 to
25 mm long.

The male moth has a thick black hair tuft on its fore tibia.
The dorsal part of its abdominal tip has a thin and very long
longitudinal black band. The male has a wingspan of 14 to 16
mm.
The female moth has a longer wingspan of 16 to 18 mm.
Pupa
The pupa is light brown or bright brown. With age, it
turns reddish brown. It is 9 to 12 mm long.
Adult
The adult is whitish yellow or
golden yellow. It has three
black bands on the forewings,
two are complete bands and
one is an incomplete middle
band.

 Feeding damage of the rice leaf
folder includes folded leaves and
removal of leaf tissue, leaving
longitudinal and transparent
streaks. The streaks are whitish.
 The folded leaves are tubular
where the larvae conceal
themselves to feed. Sometimes,
the tips are fastened to the basal
part of the leaf.
 Heavily infested fields show many
folded leaves and a scorched
appearance of leaf blades.
Nature of damage

Rice hispa : Dicladispa (= Hispa) armigera Olivier
• Causes leaf defoliation damage to rice crops
over large areas in Bangladesh, India, and
Indonesia.
• Extensively damaged plants may be less
vigorous and stunted.
• The rice hispa seems to be a perpetual
problem in Bangladesh. It infests about
120,000 hectares, causing an estimated loss of
20% in yield.

Adult
The adult is blue-black and very shiny. Its
wings have many spines. It is 5.5 mm long.
Egg
The white egg is small and oval. It measures
1-1.5 mm long. A small dark substance
secreted by the female covers each egg. As
the egg matures, it turns yellow.
Pupa
The brown pupa is round and
about 4.6 mm long.
Larva
The larva or grub is white to pale yellow. A younger grub
measures 2.5 mm long, whereas a mature larva is about
5.5 mm long and 1.6 mm broad.

• Both adults and grubs feed on and damage the plants.
• The adults scrape the upper surface of the leaf blade leaving
the lower epidermis.
• Damaged areas appear as white streaks parallel to the midrib.
• Tunneling of the grubs results in irregular translucent white
patches.
• The affected parts wither off.
• The leaves also turn whitish and membranous.
• Severe infestation causes the field to appear burned.
Nature of damage

Plant hoppers
Brown plant hopper (BPH) (Nilaparvatha lugens)
White backed planthopper (WBPH) (Sogatella furcifera)
Brown planthoppers (BPH) suck the
sap of the leaf blades and leaf sheaths,
causing the yellowing of the plants.
Hopperburn or complete drying of the
plants is observed at a high population
density of the insects. At this level, the
loss is considered 100%.

Adults
The adult is brownish black with a distinct white band
on its mesonotum and dark brown outer sides. The
body is yellowish brown. The adults have two distinct
winged forms, macropterous and brachypterous.
Macropterous forms have normal front and hind wings,
whereas brachypterous forms have reduced hind
wings.

Eggs
are crescent-shaped, 0.99 mm long and 0.2 mm
wide. Some of the eggs are united near the base
of the egg cap and others remain free. When
freshly laid, the eggs are whitish, but later
become darker. Before egg hatching, two distinct
spots appear, representing the eyes of the
developing nymph.
Nymphs
The newly hatched nymphs are 0.91 mm long
and 0.37 mm wide. The head is triangular with a
narrow vertex. The body is creamy white with a
pale brown tinge. The nymphs molt five times.
The fully developed nymph is 2.99 mm long and
1.25 mm wide. There is a prominent median line
from the base of the vertex to the end of the
metathorax where it is the widest. This line
crosses at a right angle to the partition line
between the prothorax and mesothorax.

• Both BPH and WBPH nymphs and adults damage the
plants by sucking phloem sap
• Reduced vigour, stunting, yellowing, delayed tillering and
grain formation.
• At later stages, crop dries up in patches known as hopper
burn.
• BPH also transmit virus disease called grassy stunt.
Nature of damage

• Leaf hoppers adult and nymphs
suck the sap from the leaves
which is characterized by small
scratch like marks on the leaf due
to chlorophyll removal.
Leaf hoppers
Green leaf hopper
Nephotettix virescens
N. nigropictus
Zigzag leaf hopper
Racilia dorsalis
EIL 10 GLH/hill at vegetative stage
20 GLH/hill at flowering stage

Nephotettix nigropictus
Adult
The adult is slender and green with a
rounded vertex.
Vertex has an anterior black band
and a sub-marginal black band
extending beyond the ocelli to the
inner margins of the eyes.
Its pronotum is smooth with a black
anterior margin. Black spots are
prominent on the forewings. The
female hopper measures 4.3 by 1.4
mm, whereas the male is 3.7 by 1.3
mm.
 Less efficient virus transmitter
 Transmits tungro, yellow dwarf, dwarf, and transitory
yellowing diseases.

Green leafhoppers are important pests. They are vectors
of viruses such as tungro, yellow dwarf, and transitory
yellowing.
 The adult leafhopper is green.
 Its head has a pointed vertex
without black bands.
 The face is also green.
 A pair of black spots is either
present or absent on the tegmen
of the forewings.
 A male hopper measures 4.2 by
0.05 mm, whereas the female is
4.3 by 1.4 mm.
Nephotettix virescens

Recilia dorsalis
In large numbers, this insect
can transmit rice tungro, rice
dwarf, and rice orange leaf
viruses
 Adult hoppers has zigzag white and brown pattern on the
front wings.
 The body of the female adult is 3.5-3.8 mm long, whereas the
male is 3.1-3.4 mm long.

This sporadic pest occasionally causes losses. It can
be destructive when an outbreak occurs. Mature
panicles are cut off from the base or peduncles. The
host plant may be totally devoured when
populations are very high.
Caterpillars feed on leaves in night and in severe
infestation entire seed beds and fields are destroyed
and the field appears as if it has been grazed by
animals/ cattle
Rice armyworm :: Mythimna separata (Walker)

Egg
The eggs are subspherical and greenish
white. With age, they turn yellow.
Adult
The adult is more than 15.0 mm in length. Its
forewings are pale red-brown with two pale round
spots. Its hindwings have two colors, dark red-
brown on top and white underneath.
Larva
Young larvae have two pairs of
prolegs. Mature larvae are
green to pink with longitudinal
light gray to black stripes
running along the entire length
of the body. They are 31.0 to
45.0 mm long. They have a
brown to orange head with an
A-marking on the frons.
Pupa
The pupa is 17.0
to 20.0 mm long.
It is dark brown.

The larvae feed on the leaves by removing the epidermis
leaving the leaf tissues. Excessive feeding causes
complete removal of whole leaves and plants. The rice
panicles can also be cut off from the peduncles.
Nature of damage

Rice thrips : Stenchaetothrips biformis
This is a pest during the seedling stage or 2
weeks after early sowing. It is a serious pest
during the dry season.
Losses can reach 100% where infestation is
severe for the first 20 days in direct-seeded
rice fields.

• Egg
The egg is very tiny. A single egg is 0.25 mm long and 0.1
mm wide. It is hyaline when freshly laid and turns pale
yellow toward maturation.
• Larva
Neonate larvae are colorless. They become pale yellow in
the second larval instar. The legs, head, and antennae of the
second instar larvae are slightly darker than those of the
first instar larvae.
• Prepupa
The prepupa is brown. Four pointed processes are present
on the hind margin of the ninth abdominal tergite.
• Pupa
The pupa has long wing pads that reach two-thirds the
length of the abdomen. It also has four pointed processes
on the ninth abdominal tergite.
• Adult
The minute adult has a slender body. It is dark brown. It is 1-
2 mm long with well-pronounced 5 to 8 segmented
antennae. It exists in two forms, winged or wingless. The
winged form has two pairs of elongated narrow wings that
are fringed with long hairs.

.
Nature of damage
• Feeding damage causes laceration of plant tissues.
• Damaged leaves become noticeable as silvery streaks
or yellowish patches.
• The translucent epidermis becomes visible on the
damaged area.
• Curling of the leaves from the margin to the middle is
also visible.
• In severe infestation, the leaf tips wither off.
• Infestation at the panicle stage causes unfilled grains

Both the nymphs and adults feed on the leaf and can
consume large amounts of leaves.
Grasshopper : Oxya hyla intricata
Adult
Oxya hyla intricata are small to medium and
moderately slender insects. They measure up
to 20 mm in length. Their eyes are large and
close to each other. They have a sub-
cylindrical pronotum with a rounded posterior
margin. The height of the pronotum is lower
than the head. Their wings are fully
developed in both sexes. Their green hind
femora are slender with upper knee lobes
rounded and lower knee lobes extended into
acute spine-like projections. They have
greenish tibiae. Their wings are green with
brownish to bluish bands.
The antennae are filiform in type. The
antennae of the male are slightly longer than
the head and pronotum combined. The
female has shorter antennae.
Egg
The eggs are
capsule-like
and yellow.
Nymph
The nymph is a smaller
version of the adult except for
the presence of small wing
pads.

Integrated DiseaseIntegrated Disease
Management in RiceManagement in Rice

Major Diseases of RiceMajor Diseases of Rice
• Blast (Pyricularia oryzae)
• Brown spot (Helminthosporium oryzae)
• Stem rot (Sclerotium oryzae)
• Bacterial leaf blight (Xanthomonas oryzae)

Blast diseaseBlast disease
• Most plant parts are susceptible to infection except the
roots.
• Disease usually develops during seedling, tillering (leaf blast)
and at heading (panicle blast).
• The initial infections start as small water soaked areas on
young leaves and enlarge into diamond shape with a blue
gray cast which are the fungal spores. Lesions often dry out
and turn tan with a brown border. Lesion shape and size can
vary.

Head infections develop at the joint just below
the head (neck blast) or on individual panicle
branches (panicle blast). The head can break off
at neck lesion can cause rotten neck blast.

The fungus produces many spores ,on
stalk like structures called sporangia, in
the presence of a favorable environment
and a susceptible host and causes
numerous new infections in the field and
neighboring fields. They are carried by
wind and water over long distances.

ManagementManagement
• Blast development is favored by thick stands
and high nitrogen rates which increase
canopy thickness resulting in higher moisture
levels but is most severe under upland or
drained conditions. Other conditions that
favor blast are sandy soils and fields lined
with trees.

Management contd.Management contd.
• Plant varieties resistant to blast.
• Avoid late planting.
• Plant as early as possible within the
recommended planting period.
• For leaf blast, re-flood if field has been
drained. Maintain flood at 4 -6 inches to
ensure soil is covered.
• Do not over fertilize with nitrogen.
• Apply a fungicide if necessary.

Management of brown spotManagement of brown spot
• Treat the seeds with 0.2% Thiram
• Avoid water stress
• Give balanced nutrition
• Use resistant varieties
• Spray Tricyclazole

Stem rotStem rot
Black angular lesions on
leaf sheath at or near
water line on plants at
tillering or early jointing
growth stages; later
sheath may dye and
culms have dark-brown
or black streaks, at
maturity culms may
collapse and small
round black sclerotia
form in dead tissues.

ManagementManagement
• Fungicides are available to control stem rot
however infestation levels seldom reach
economic levels to justify spraying and no
economic thresholds have been developed.
Stem rot is usually detected when scouting
for sheath blight. Fungicide applications
targeted at other diseases can reduce stem
rot severity.

Foot rot/ Bakanae
• Caused by fungus Fusarium moniliforme.
• The general symptoms of this disease is that
infected plants die at grain filling period, and
they bear only white empty panicles.
• A white or pink growth of the pathogenic
fungus may be noticed on the lower parts of
diseased plants.

• Some other symptoms may be observed in early
stages: infected seedlings are taller than normal
plants and are thin and yellowish-green at the
seedling stage,
• Bakanae symptoms can be seen in the vegetative
stage, infected plants are taller than the normal
plants and have a few tillers and yellow-green
leaves.
• The most important damage occurs at the grain
filling period.

Foot rot/ SymptomsFoot rot/ Symptoms

Management
• Produce basmati seed from disease free aress.
• Treat seed with suitable fungicide e.g. Benlate
• Destroy stubble and crop debris.
• Rogue out infected plants
• Adopt crop rotation
• Grow less susceptible varieties
• Use balance fertilizers

Bacterial blight
• Symptoms
• Small, green water-soaked spots develop at the
tips and margins of fully developed leaves, and
then expand along the veins, merge and become
chlorotic then necrotic forming opaque,
• White to grey colored lesions that extend from
leaf tip down along the leaf veins and margins.
Both bacterial blight and bacterial leaf streak can
occur simultaneously and are difficult to
distinguish

. caused by Xanthomonas oryzae

Factors favoring disease development
• presence of weeds
• presence of rice stubbles and ratoons of
infected plants
• presence of bacteria in the rice paddy and
irrigation canals
• warm temperature, high humidity, rain and
deep water
• over fertilization
• handling of seedlings at transplanting

Management principles
• Practicing field sanitation such as removing
weed hosts, rice straws, ratoons, and
volunteer seedlings is important to avoid
infection caused by this disease.
• Likewise, maintaining shallow water in nursery
beds, providing good drainage during severe
flooding, plowing under rice stubble and straw
following harvest are also management
practices that can be followed

. Proper application of fertilizer, especially
nitrogen, and proper plant spacing are
recommended for the management of
bacterial leaf blight.

Harvesting
Harvesting at proper time ensure grain quality, a
high market value and improved consumer
acceptance.
Harvesting should be done between 27 to 39
days after flowering.
Harvesting is done by
• Manual with sickle
• By using Combine harvester

Content
• Introduction
• What is harvesting
• Harvesting systems
• When to harvest
• How to harvest
(technology options)
• Harvest losses
• Recommendations

Introduction
Harvesting is the process of collecting
the mature rice crop from the field.
• Cutting: cutting the panicles and straw.
• Hauling: moving the cut crop to the threshing
location.
• Threshing: separating the paddy grain from
the rest of the cut crop.
• Cleaning: removing immature, unfilled and
non-grain materials.
• Field drying: (optional) leaving the cut crop in
the field and exposing it to the sun for drying.
• Stacking / Piling: (optional) temporarily
storing the harvested crop in stacks or piles.

Good harvesting practices
Goals of good harvesting:
• maximize grain yield
(minimize losses)
• minimize grain damage
• Minimize quality
deterioration
• Heat build up from mold and
insect development
• Discoloration/Yellowing from
heat build-up
• Cracking from re-wetting of
dried grains
• Loss of vigor
• Reduced head rice yield
• Shattering losses
At harvest the quality of rice is best.
From then on it can deteriorate
quickly:

Harvesting systems
1. Manual system
• Manual
operation
sometimes using
tools
• Labor
requirement: 48
person days / ha

Harvesting systems
2. Manual cutting / machine threshing
• Labor requirement: 28 person days/ha
• Capital cost appr.: US$ 1000
Optional:
Winnowing
or
cleaning

Harvesting systems
2. Machine cutting / machine threshing
• Capacity reaper:
• Capacity thresher:
• Capital cost approx.: US$ 2,500
Optional:
Winnowing
or
cleaning

Harvesting systems
4. Combine harvesting
• Cutting, hauling,
threshing, cleaning in
one combined
operation
• Capacity: > 0.5 ha/h
• Labor requirement: 1
Operator
• Capital cost: > $
250,000

When to harvest
Harvest rice when:
• 20-25% grain moisture
• 80-85% straw colored and
• the grains in the lower part
of the panicle are in the
hard dough stage
• 30 days after flowering

Manual cutting and hauling
• Capacity: 0.07 ha/person day
• Advantages
– effective in lodged crop
– less weather dependent
• Problems
– high labor cost
– labor dependent, competes with
other operations in peak season
– winnowing/cleaning necessary

Mechanical reaping
• Capacity: 2-4 ha/d
• Advantages
– Fast cutting
• Problems
– Places crop in window
back in the field
– Problem with lodged
crop
– Complex cutter bar and
conveying mechanism

Manual threshing
• Capacity: approximately
15 person days/ha
• Threshing by impact
• High shattering losses
• Pre-drying might be
needed

Pedal thresher
• Capacity:
• Principle
– Wire loop threshing drum
– Mainly combing the grains
off the straw, some
threshing by impact
• Advantages
– Maintains the straw
• Disadvantage
– Needs winnowing after
threshing
Wire loop threshing drum

Axial-flow thresher
• Capacity: 0.3-3t/h
• Threshing through
impact
• Large range of sizes
available
• With or without cleaner
• Truck mounted units
• Advantages
– Can thresh wet crop
– Compact
roduced in 9 different countries
sed by several 100,000’s of rice farmers across Asia
Peg tooth
threshing
drumAxial flow principle

Winnowing
• Principle: lighter
materials are blown
away by air
• Removes chaff, straw
and empty grains
• Hand or mechanical
winnowing
• Does not work for
materials heavier than
grain (dirt, stones)

Cleaning
• Combination of fan and
oscillating sieves
• Air delivered by fan
removes lighter
materials
• Top sieves with large
holes remove larger
straw particles
• Bottom sieves with
smaller holes remove
small seeds (e.g. weed
seeds)

Combine harvesting
• Features
– capacity: 4-8 ha/day
– combines cutting, threshing,
cleaning and hauling
– tracks for mobility in wet fields
• Advantages
– high capacity
– low total harvest losses
• Disadvantages
– Requires relatively large field sizes
– Problem in terraced fields

Stripper harvesting
• Capacity: 1ha/day
• Advantages
– strips and collects
grains only
– less material to handle
• Problems
– problems in wet soils
and lodged crop
– straw treatment
– does not work well
with long straw
– complex machine
– skills required
Despite strong promotion in SE-Asia
the stripper harvester has not gained
wide popularity because of its
problems in less favorable harvesting
conditions

Losses during cutting
• Shattering loss = premature shedding of mature
grains from the panicle caused by birds, wind,
rats, and handling operations. Certain rice
varieties shatter more easily than others.
• Lodging loss = plants with mature grains in the
panicles fall on the ground making the grains
difficult to recover.
• Standing crop loss = standing plants with mature
grains are left standing in the field after
harvesting operations as a result of oversight,
carelessness or haste.

Losses during threshing
• Separation loss or “blower loss” = mature grains
that are mixed with straw or chaff during the
cleaning operation.
• Scatter loss = mature grains that are scattered on
the ground during the threshing and cleaning
operation.
• Threshing loss = mature grains that remain
attached to the panicle in the straw after
completion of the threshing operation. High
threshing efficiency will lead to low threshing
loss, and vice versa.

Recommendations for optimizing quality
• Harvest at the right time and moisture content
• Avoid stacking the cut crop in the field
• Avoid delays in threshing after harvesting
• Use the proper machine settings when using a
threshing machine
• Clean the grain properly after threshing
• Avoid delay in drying after threshing

Tips for manual threshing
• Thresh as soon as
possible after cutting
• Hand thresh at lower
moisture
• Place a large canvas
under the threshing
frame to minimize
shatter loss

Tips for machine threshing
• Thresh as soon as possible
after cutting
• Level the thresher
• Set machine correctly
– drum speeds in thresher
(600rpm)
– air flow in the cleaner
– angle in the cleaner
sieves

Tips for good winnowing
• Place grain on a winnowing tray
• Place a net or mat on the ground
• Tilt the tray against the wind
• Pour grain slowly at a height of about
1m
• Wind will separate light from heavy
grains
• Recover only the heavier grains
• Repeat the procedure, if needed
• Use a fan or blower if there is
insufficient wind.

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