biology of economic agriculture

1. MAIZE / CORN

2. DOMESTICATED OF THE MAIZE
Maize was domesticated from its wild grass
ancestor more than 8,700 years ago in
Central America.
The wild grass called teosinte.

3. DOMESTICATION
- process which plant genetically modified over
time by humans for traits that are more
advantageous or disirable for human
- Teosinte is the ancestor of maize
- Had bigger kernels and more rows of kernels
- Over the time they select other useful traits and
lastly a new type was form known as maize
- The effect of this situation plant cannot survive
in wild without human

4. -Teosinte is a short and a bushy plants
-This difference because of the difference of
the two genes

5.  The corn most planted in several region in
Malaysia :
-Johor
-Selangor
-Pahang
-Also used as the vegetable known as baby
corn

6. HISTORY
 In western civilization, the story of corn
began in 1492 when Columbus's men
discovered this new grain in Cuba
 Exported to Europe
 Corn in the United States is also called
maize or Indian corn
 Corn in England means wheat; in Scotland
and Ireland, it refers to oats

7. WORLD PRODUCTION
Country Maize area, ha Maize production, Mt Yield, Mt/ha
WORLD 159,531,007 817,110,509 5.12
USA 32,209,277 333,010,910 10.34
China 30,478,998 163,118,097 5.35
Brazil 13,791,219 51,232,447 3.71
India 8,400,000 17,300,000 2.06
Mexico 7,200,000 20,202,600 2.81
Argentina 2,337,175 13,121,380 5.61
 http://www.nue.okstate.edu/Crop_Information/World_Wheat_Production.htm

8.  http://nutritiondata.self.com/facts/vegetables-and-vegetable-products/2415/2

9. USES
Human food
 Alternative medicine
Chemicals
 Bio-fuel
 Ornamental and other uses
Fodder
Commodity

10. PRODUCT BASED ON MAIZE

11. GROWTH FACTOR
AND LAND
PREPARATION

12. OUTLINE
•Climate requirements
•Soil requirements
•Planting depth and plant
technique
Growth
Factor
• Weeds removing
• Soil tillage
• Fertilisation of land
Land
Preparation

13. GROWTH
FACTOR

14. CLIMATE REQUIRE
 Maize crops is strongly affected by climate such
as :
 Temperature
 Water / Moisture

15. TEMPERATURE
 Maize is a warm weather crops of 19˚C to 23˚C.
 The critical temperature affecting yield is
approximately 32˚C.
 Low temperature will cause frost at all stages of
maize.
 Frost free period is require to prevent damage
between 120-140 days.

16. FROST INJURY

17. WATER / MOISTURE
 Approximately 10-16kg of grain are produce per
millimetre of water use.
 At maturity, each plant will used 250l of water in
absence of moisture stress.
 The yield loss due to water stress will depend
on the growth stage of corn during the drought
stress as well as the length and severity of the
drought.

18.  Corn is most sensitive to water stress during
pollination, followed by grain-filling, and
vegetative growth stages.
 Water stress during vegetative growth stages
results in reduced plant height and leaf area,
and lower yield potential.
 Moisture stress during pollination is the most
critical for reducing yield potential of corn.

19. WATER STRESS DROUGHT STRESS

20. SOIL REQUIREMENT
 Most suitable soil for maize is
Good
effective
depth
Optimal
moisture
regime
Good internal
drainage
Sufficient and
balance plant
nutrient
Favourable
morphological
properties
Favourable
chemical
properties

21.  Maize production take place on soils with a clay
content of less than 10% sandy soils or in
excess 30% clay and clay-loam, texture classes
between 10 and 30% have air and moisture
regimes

22. Land preparation. Deep ploughing up to 45
cm is favourable for maize that have deep
growth. Ridges can be made at 60cm apart
for maize planting.

23. LAND
PREPARATION

24. WEEDS REMOVING
 The most critical period of weed competition is
during the first four to six weeks after emergence
of the crop.
 Weeds compete with the maize plant for water,
nutrients, space and light
 Some weeds become alternative hosts of pests
and diseases.
 Some weeds are parasitic and poisonous to
maize

25. EFFECTS OF WEEDS ON MAIZE

26. FERTILISATION OF LAND
 Base fertilizer expected yields and crop needs
adjusted for residual available nutrients in the
soil
 Manure is a common source of nutrients and is
beneficial when applied to recently levelled land
 Yields can be expected increase 5% without
influence by other factors such as frost, weeds
and others

27. TYPES OF MANURE

28. SOIL TILLAGE
 Soil tillage in a farming system refers to the
physical soil cultivation practices, changing the
soil’s structure, hydraulic properties and stability.
 Most important processes affected by soil tillage
include infiltration and evaporation of water.
 Germination and root growth
 Erosion

29.  aims of soil tillage are weed control,
incorporation of residue, reducing wind and
water erosion, improving soil structure and
prepare seedbed

30. PEST OF MAIZE

31. PEST
1. FLEA BEETLE (PHYLLOTRETA VITTULA)
 small, shiny beetles with black legs
enlarged for jumping
 Symptom:
-leaving tiny pits or small holes at their
feeding sites
-It can cover leaves with bleached, pitted
areas or ragged holes

32.  Controls:
- Seedlings can be protected with protective
covering until they are in the sixth leaf stage.
- Remove debris in the fall to remove any
overwintering beetles.
- applied reflective mulches
- insecticides should not normally be necessary
and are not very effective when populations are
high.

33. 2. SEEDCORN MAGGOT
(DELIA PLATURA MEIGEN)
 yellowish-white maggot found burrowing into corn
seeds.
 Full grown maggots are legless, about 1/4 inch (6
mm) long
 It is cylindrical, narrow and tapered and it also has
heads and legs, but have small black mouth hooks
in front.
 It burrow into the seed, often destroying the germ

35.  Symptoms:
- It will damaged the seed because there are not
enough food reserves left in the seed for the plant to
survive.
- attack the underground stems of sprouted corn and
soybeans resulting in weakened seedlings that
seldom survive.
 Control:
- seed treatment
- Insecticides
- Replanting
- to remain healthy plant population, the date, yield
expectation.

36. 3. STALK BORER (PAPAIPEMA NEBRIS
)
Attack :
•Base of plant and centre of the stalk
Symptoms :
•Round to irregular shaped rows of holes
• Wilting or dying of the upper leaves
•Plants are often stunted or misshapen and
may die.

37. CONTROL :
-ANY WEED CONTROL METHOD THAT HELPS ELIMINATE
GRASSES WILL REDUCE THE NUMBER OF POTENTIAL
STALK BORER EGG-LAYING SITES, REDUCING THE
PROBABILITY OF STALK BORER DAMAGE THE NEXT YEAR
-BURNING THE DAMAGED AREAS BEFORE EGGS HATCH
CAN REDUCE COMMON STALK BORER POPULATIONS

38. Larvae can damage corn seeds shortly after planting
Attack :
 Fibrous root plant
Symptoms :
4. WIREWORMS (AGROITES MANCUS)
 Shredding and discolouration plant but still
attached to the root
 Small dark wounds on the stems
Control :
 Apply granular insecticide
 Bait balls
 Soil insecticides approved for use to control corn rootworms include:
Aztec 2.1G, Force 1.5G and 3G, Fortress 2.5G and 5G, and Lorsban
15G.
 Usually, prevention of wireworm damage requires treatment before or at
planting time.

39. 5. OSTRINIA NUBILALIS (CORN
BORER)
Also known as the European high-flyer
 Attack: Damage the ears of corn, as
well as the stalks, by chewing tunnels, which can
cause the plants to fall over.
 Symptom: In corn, European corn borers feed
first on the leaves, then move to the tassels and pollen. Older
larvae bore into the stalks and ears.
 Ways to control:
- Clear the garden of all weed debris and plant stalks.
- Destroy all corn stalks after harvest.
- Attract beneficial insects, especially lacewings, lady beetles,
and predatory or parasitic wasps.

40. 6.
BILLBUG
 Attack: Adults gouge small holes in the stem to feed
on the tender inner plant tissue.
 Symptoms: - Adult billbugs chew holes in grass
stems, usually just above the crown to
create an egg-laying site.
- Larvae begin to tunnel within the stem
upon hatching, then burrow into the
crown.
- Older larvae will feed on the crown, and can kill
plants.
 Ways to control: 1) Cultural Control - Use Resistant Turf
Varieties
2) Biological Control - Predation by birds and
hunting wasp.
- Insect parasite nematodes
(Steinernema sp)
3) Chemical Control - Insecticides

41. DISEASE OF MAIZE / CORN
Zea mays subsp. mays

42. DISEASE NAME: SEED ROT
 Pathogen: Fungi and bacteria.
Pythium, Fusarium, Diplodia,
Rhizoctonia, Penicillium spp.,
various soilborne bacteria
 Symptoms: The seed rots
(embryo is killed) before
germination.
 Inoculum survival: Soil, infected
plant residue (leaves, stems,
roots), occasionally infected seed.
 Control : Fungicide seed
treatment. Plant when soil
conditions are warmer and drier,
use the proper planting depth.
.
SEED AND SEEDLING DISEASE

43. DISEASE NAME: GRAY
LEAF SPOT
 Pathogen: Fungus. Cercospora
zeae-maydis
 Symptoms: Initial lesions appear as
greenish black water soaked
circular areas with chlorotic halos,
expanding into oval and then the
diagnostic parallel sided rectangular
brownish gray lesions.
 Inoculum Survival: Infected crop
residue (leaves and leaf sheaths).
 Control : Select hybrids with
resistance (tolerance based on risk),
two year crop rotation, cleanly plow
under infected residue.
LEAF DISEASE
.

44. DISEASE NAME: SOUTHERN CORN RUST
.
 Pathogen: Fungus. Puccinia
polysora
 Symptoms: Similar to common
rust except pustules occur almost
exclusively on the upper leaf
surface, rarely on lower. Pustules
are more orange than brick-red
and slower to break through
epidermis of leaf than common
rust pustules.
 Inoculum Survival: Spores
blown into the Midwest from the
South. Does not survive winter in
Indiana, except possibly in rare
years along the Ohio River.
 Control : Resistant hybrids.
Foliar fungicides may be useful in
seed production fields.
.

45. DISEASE NAME: ANTHRACNOSE
STALK ROT
 Pathogen: Fungus. Colletotrichum
graminicola
 Symptoms:Water-soaked areas on the
surface of the lower internodes,
developing brownish linear streaks,
turning black later in the season, larger
oval black areas may develop,
disintegrated gray to dark brown pith,
severely infected stalks likely to lodge.
 Inoculum Survival: Infected crop
residue (leaves, leaf sheaths and stalks),
infected seed (rare).
 Control Resistant hybrids (full season
hybrids tend to have more resistance
than short season), two year crop
rotation with non grass crops, cleanly
plow under infected residue, balanced
soil fertility.
STALK ROTS
.

46. DISEASE NAME: DIPLODIA
STALK ROT
.
 Pathogen: Fungus. Diplodia maydis
 Symptoms: Leaves turn grayish-green
and eventually brown. Dark
brown lesions extend in either
direction from the node. Pith is
disintegrated and discolored, stalks
break easily. Tiny black bumps
(pycnidia) may form just beneath the
epidermis on lower internodes.
 Inoculum Survival: Infected crop
residue (seed, cobs, ear shanks,
stalks),seed, soil.
 Control : Resistant hybrids (full
season hybrids tend to have more
resistance than short season hybrids),
balanced soil fertility, recommended
plant population.
.

47. DISEASE
NAME: GIBBERELLA STALK
ROT
 Pathogen: Fungus. Gibberella
.
zeae
 Symptoms: Stalks that are split
open have a disintegrated pith
with pink discoloration.
 Inoculum Survival: Infected
crop residue (seed,stalks), seed,
soil.
 Control : Resistant hybrids. Full
season hybrids tend to have more
resistance than short season.
Balanced soil fertility. Do not
exceed recommended plant
populations.
.

48. DISEASE NAME: DIPLODIA EAR
ROT
 Pathogen: Fungus. Diplodia maydis
 Symptoms: Infection usually starts at the
base of the ear or from the stalk into the
shank. White mycelial growth covers the
kernels and pycnidia may be found on
rotted kernels, husks adhere tightly,
infected ears remain erect when infection
occurs early in ear development.
 Inoculum Survival: Infected crop residue
(seed, cobs, ear shanks, stalks), soil.
 Control : Resistant hybrids, crop rotation,
clean plowing, harvest early to prevent
weathering. Dry corn to 15% moisture
content and below to prevent further mold
growth in storage.
EAR ROTS
.

49. DISEASE NAME: GIBBERELLA EAR
ROT
 Pathogen: Fungus. Gibberella zeae
 Symptoms: Reddish mold that usually
.
starts at the tip of the ear. Husks may
adhere tightly to the ear (hybrid
dependent).
 Inoculum Survival: Infected crop
residue (stalks, seed), infected seed,
soil.
 Control : Resistant hybrids, crop
rotation, harvest early to prevent
continued mold growth in the field,
clean plowing. Dry corn to 15%
moisture content and below to prevent
further mold growth in storage.
.

50. DISEASE NAME: ASPERGILLUS EAR
ROT
.
 Pathogen: Fungi. Aspergillus flavus,
A. glaucus, A. niger
 Symptoms: Aspergillus niger appears
as a black mold on infected
kernels. A. flavus is a greenish-yellow
mold growing on damaged kernels. A.
glaucus is a greenish mold.
 Inoculum Survival: Infected plant
residue, infected seed, soil.
 Control : In storage, controlled by
drying corn to a moisture content
below 15% as soon after harvest as
possible. In the field, avoid insect or
mechanical damage to ears.
.

51. DISEASE NAME: MAIZE DWARF
MOSAIC
 Pathogen: Virus. Maize dwarf
mosaic virus (MDMV) strain A or B
 Symptoms: Stippled mottle or
mosaic of light and dark green on the
youngest leaves (may develop into
narrow streaks). Upper internodes
may be shortened. Older leaves may
become blotched with red streaks
 Inoculum Survival: Weeds
(rhizomes of perennial Johnsongrass).
 Control : Resistant hybrids, control
OTHER DISEASE
rhizome Johnsongrass or other
overwintering weed hosts.
.

52. DISEASE NAME: MAIZE CHLOROTIC
DWARF
.
 Pathogen: Virus. Maize chlorotic
dwarf virus (MCDV)
 Symptoms: Fine chlorotic striping
is first evident on smallest visible
leaf veins. Older leaves may exhibit
reddening, yellowing and marginal
necrosis
 Inoculum Survival: Weeds
(rhizomes of perennial
Johnsongrass).
 Control: Resistant varieties. Sow
early in the growing season to avoid
large leaf hopper populations.
Control perennial Johnsongrass.
.

53. TITLE :
HARVEST & POST-HARVEST

54. MAIZE HARVESTING PROCESS
Harvest time
Harvesting
process
requirement
Before
Harvesting
After
Harvesting
Losses due to
poor storage
Conditions that
favour aflatoxin
contamination
in maize grains
Losses due to
mould

55. HARVEST TIME :
The optimum time of harvesting
maize is when the stalks have
dried and moisture of grain as
about 20-17%.

56. HARVESTING PROCESS
REQUIREMENT :
* Harvest maize as soon as it is dry but not
overstay in field it will be attacked by weevils
if does and lodge.
* In addition to reducing post
harvest losses, this will also release the field
for early land preparation.
* Keep the grain as clean as possible.
*Dry maize
on cement floor or use tarpaulin to reduce
chance of contamination.
* Dry on concrete or canvas not on bare soil.

57. PRE-HARVESTING :
• Make sure the drying place or equipment is clean and
disinfected, ready to receive the cobs.
• Remove old grain and dirt from anything that will come in
contact with the good or new grain. This includes harvesting
tools, carts, wheel barrows, bags and baskets.
• Where possible, fumigate them or at least treat them with
boiling water to kill insects or their eggs. This is done in
order to avoid infection of new grain by insects and their
eggs.
• Organize enough labour to reap and carry the cobs to the
drying place.

58. POST-HARVESTING :
 Drying - the systematic reduction of crop moisture
down to safe levels for storage, usually 12%-15.5%
moisture content. It is one of the key post harvest
operations since all down-stream operations depend
on it.
 Shelling – It is commonly done by beating maize
cobs with stick in a sack or a confined floor space
where farmers can afford it.
 Storage - to maintain the stored grains in good
condition so as to avoid deterioration both in
quantity and quality.

59. LOSSES DUE TO POOR STORAGE
:
* Mould
• Microbial infection in storage occurs due to
inadequate drying of produce. The situation is
made worse when there are large numbers of
insects present or when the stored crop is
exposed to high humidity or actual wetting due
to poor storage management. Fungal infection
results into rots and development of aflatoxins,
which are poisonous compounds to live stock
and cause cancer in human.

60. CONDITIONS THAT FAVOUR
AFLATOXIN CONTAMINATION IN
MAIZE GRAINS : Aflatoxin contamination is encouraged by:
• Physical damage due to poor shelling/threshing methods
• Poor storage methods (exposure to moist condition)
• Insect infestations.
• Inadequate drying
• Aflatoxin cannot be seen with a naked eye. However, suspect materials
tend to:
• Be rotten
• Be mouldy
• Be discoloured
• Have unpleasant smell
• Have bitter taste
• Have poor milling quality
• Be warmer than room temperature

61. LOSSES DUE TO MOULD :
• Loss of weight
• Loss of quality (smell, taste, colour, nutritional
value, germination)
• Further increase in temperature and moisture,
causing more grain deterioration.

62. THANK YOU!! 