Sweet corn package of practices

given all details reg.....Sweetcorn

1. SWEET CORN PACKAGE OF PRACTICES

2. •Climate:
•Corn grows best in air temperatures from 60° to 95°F.
•Soil:
•sandy to clayey. But it performs best on well drained, aerated deep-loams
and silt loams containing organic matter and nutrients. Maize may be raised
on moderately acid soils, but the optimum Ph range is from 6.5 to 7.5.
•Season:
•Kharif: June, July
•Rabi: Oct to Jan
•Life cycle: 70 to100 days
•Field preparation:
1 Application of FYM or compost 12.5t/ha + Azospirillum 2000g/ha.
2.Ploughing twice.
3.Ridges and Furrows method:
Ridges should be 60-75cm apart.

3. •Application of fertilizer:
• General recommendation 135:62.5:50kg/ha, apply quarter of the dose N and
full dose of P2O and K2O basally before sowing.
•Seed rate: 20 to 25 kg/h.
•Spacing: 25cm between plants. Row to row 60cm.
•Population: 6 to 7 plants/sq.feet
•Seed Treatment: 1kg of seeds Monocrotophos 36wsc/ 4ml
imidacloprid 10g/kg + 0.50 ml gum in 20lt of water. For fungus Metalaxyl 2g/kg
for downy mildew and crazy top.

4. •Weed management:
•
Apply Atrazine 0.25kg/ha as preemergence before 3 to 5 days.
•Water management:
•Maize requires about 6-10 irrigations depending upon the maturity of a grown
hybrid/variety. Critical stages of water requirement in maize crop which restrict
yield are tasselling, silking, and milk formation and dough stages. Maize
sensitive to water stagnation at seedling stage and water stress at flowering,
grain-filling and dough stages.

5. PESTS IN SWEET CORN

6. African black beetle
Heteronychus arator
•Larvae feed on plant roots, reducing
growth and potentially killing small
plants. Adults can cause major damage
by chewing the bases of plants and ring
barking seedlings.

7. Control methods
•Fipronil granule 15kg/ha
•Carbofuran 3%CG 33.3 kg/ha

8. Stem borer
Chilo partellus
•Central shoot withers and leading to “dead heart”.
•Larvae mines the midrib enter the stem and feeds on the
internal tissues.
•Bore holes visible on the stem near the nodes.
•Young larva crawls and feeds on tender folded leaves causing
typical “shot hole” symptom.
•Affected parts of stem may show internally tunnelling caterpillars

9. Control methods
•Mix any of the following granular insecticides with sand to make up
a total quantity of 50 kg and apply in the leaf whorls on the 20th
day of sowing
•Phorate 10% CG10 kg/ha
•Carbaryl 4% G 20 kg/ha.
• For stem borer, release egg p[arasitoid Trichogramma chilonis @
2,50,000 /ha coinciding egg laying period. Three releases at
weekly interval are desirable. Third release is to be accompanied
with larval parasitoid Cotesia flavipes @ 5000/ha
•If granular insecticides are not used, spray any one of the
following :
•Carbaryl 50 WP 1 kg/ha on the 20th day of sowing (500 l of spray
fluid/ha).
•Dimethoate 30% EC 660 ml/ha

10. Stem fly
Atherigona orientalis

•Symptoms of damage
•The maggot feeds on the young
growing shoots results in “dead
hearts”.

11. Control methods
•Methyl demeton 25 EC 500 ml/ha
•Carbofuran 3%CG 33.3 kg/ha
•Dimethoate 30%EC 1155 ml/ha
•Methyl demeton 25% EC 1000 ml/ha
•Phorate 10%CG 10 kg/ha

12. Pink stem borer
Sesamia inferens
•Symptom of damage
•Pink larva enters into the stem
causing dead heart symptom.

13. Control methods
•Spray phosaloneb 35%EC at every 20 days interval

14. Corn worm/Earworm
Helicoverpa armigera
•Symptom of
damage
•Larva feeds on silk and
developing grains.

15. Control methods
•Carbaryl 10 D 25 kg/ha
•Malathion 5 D 25 kg/ha
•Phosalone 4 D 25 kg/ha
•Flubendiamide 70ml/acre
•Novaluron 100ml/lac

16. Ash weevil
Myllocerus sp.
•Symptom of damage
•larva feeds on the secondary roots
and adults on leaves.

17. Management
1. Mix any of the following granular insecticides with sand to make up
a total quantity of 50 kg and apply in the leaf whorls on the 20th
day of sowing
2. Phorate 10% CG10 kg/ha
3. Carbaryl 4% G 20 kg/ha.
4. For stem borer, release egg p[arasitoid Trichogramma chilonis @
2,50,000 /ha coinciding egg laying period. Three releases at
weekly interval are desirable. Third release is to be accompanied
with larval parasitoid Cotesia flavipes @ 5000/ha
5. If granular insecticides are not used, spray any one of the
following :
6. Carbaryl 50 WP 1 kg/ha on the 20th day of sowing (500 l of spray
fluid/ha).
7. Dimethoate 30% EC 660 ml/ha

18. Leafhopper Pyrilla perpusilla
•Symptom of damage
•Leaves become yellow
•Covered with black sooty mould
•Top leaves get dried up and
lateral buds germinate

19. Management
•Avoid excessive use of nitrogenous fertilizers
•Set up light trap
• Detrash: 150 and 210th DAP
• Release lepidopteran parasitoid:
•Epiricrania melanoleuca @8000 -10,000 cocoon /ha (or) 8 - 10 lacs egg/ha.
•Spray any one of the following on the 150th and 210th day (1000 l spray
fluid)
•Malathion 50 EC 2000 ml
•Monocrotophos 36 WSC 2000 ml

20. Aphid or Plant lice
Rhopalosiphum maidis
•Symptom of
damage
•Yellowing of leaves
•Colonies of aphids found
in central leaf whorl.

21. Management
•Mix any of the following granular insecticides with sand to make up
a total quantity of 50 kg and apply in the leaf whorls on the 20th
day of sowing
•Phorate 10% CG10 kg/ha
•Carbaryl 4% G 20 kg/ha.
• For stem borer, release egg p[arasitoid Trichogramma chilonis @
2,50,000 /ha coinciding egg laying period. Three releases at
weekly interval are desirable. Third release is to be accompanied
with larval parasitoid Cotesia flavipes @ 5000/ha
•If granular insecticides are not used, spray any one of the
following :
•Carbaryl 50 WP 1 kg/ha on the 20th day of sowing (500 l of spray
fluid/ha).
•Dimethoate 30% EC 660 ml/ha

22. Shoot bug
Peregrinus maidis
•Symptom of damage
•Plants become unhealthy stunted and
yellow.
•The leaves wither from top
downwards.
•Panicle formation is inhibited and the
plants die if attack is severe.
•Honeydew secreted by the bug causes
growth of sooty mould on
leaves.
•The midribs of the leaves turn red due
to egg-laying and may
dry up subsequently.

23. Management
•Diazine0.04%
•Dimethoate (or) 0.02%,
•Phosphomidon @ 250 ml in 450-500 litres water/ha

24. DISEASE MANAGEMENT

25. Boil smut - Ustilago maydis
•SYMPTOMS The fungus infects
•The fungus infects any rapidly growing part of the
plant, commonly the cobs, but also stems, tassels and
leaves. Pale green to grey galls form and enlarge,
reaching up to 150 mm diameter on the cobs. These
eventually burst, releasing masses of dark spores.
•FAVOURED
• Infection is increased if corn is physically damaged, as
well as by high soil nitrogen. Spores are carried on the
wind and in irrigation water.
•while resting spores on crop residues are known to
potentially survive in the soil for more than 15 years

26. Brown spot - Physoderma maydis
•SYMPTOMS Small
• oval chocolate brown lesions
develop, usually initially in the leaf
axils and whorls. Dark spots appear
along the mid ribs with lighter, rust-
like spotting on the leaf blade. Severe
infection can result in plants
collapsing.
•FAVOURED
•Warm (23–30° C) and humid
weather. Infection requires free
water, so is more likely after heavy
rain. Most common on the Atherton
Tablelands.

27. Damping off
Pythium spp., Fusarium spp., Sclerotium rolfsii, Rhizoctonia solani
•SYMPTOMS
• Crop emergence is poor.
Seedlings that do emerge
wilt, lose colour and have
stunted growth.
Watersoaked, brown lesions
appear on the emerging
stem near the soil junction
and plants may collapse.
•FAVOURED
• Wet soil conditions. The
different fungi responsible for
damping off can survive in
the soil for extended periods,
either as resting spores or in
crop residues

28. Fusarium cob rot
Fusarium vertilliodes, F. spp.
•SYMPTOMS
•White to pale pink fungal growth can
affect individual kernels or extend over
the whole cob. White streaks radiating
from the tips of individual kernels
(‘starburst’) are characteristic of the
disease. The mould produces toxins in
the infected cob.
•FAVOURED
• High temperatures and moisture
stress. Infection is more likely if
insects damage cobs or kernels split
due to uneven irrigation..

29. Head smut
Sphacelotheca reiliana
•SYMPTOMS
• Unlike boil smut, head smut only affects the
cob and silk. Tassels become distorted and
develop masses of black spores. The husks of
infected cobs grow into a teardrop shape and
lack silks. Inside, large smut galls bursting with
black spores usually replace the entire cob.
Within this mass, the vascular system remains
relatively intact, giving the spore bundle a
distinctive, stringy appearance.
•FAVOURED
•Infection usually occurs when plants are
seedlings, although symptoms are not
expressed until flowering and cob formation.
Spores can survive at least 5–7 years in cool,
dry soils with infection most likely under warm
(20–30° C), dry conditions

30. downy mildew
Peronosclerospora maydis
•SYMPTOMS
•Pale green to yellowish striping develops along
the leaf veins. These have clear borders, with
the affected area increasing as the plant grows.
Downy growth may appear on either side of the
leaf surface. Mature plants are stunted and
distorted, forming multiple or deformed cobs.
•FAVOURED
•Infection most commonly occurs in seedlings,
with plants becoming more resistant with age.
Sorghum is also a host, which is why the
disease is mainly found in drier areas.

31. leaf blight
Exserohilum turcicum
•SYMPTOMS
•Elongated grey-brown lesions
develop, often with a yellow halo.
These expand, and greyish
streaks eventually cover much of
the leaf surface. Initial infection is
often in the lower leaves. In
moist weather masses of dark
spores are produced inside the
lesions.
•FAVOURED
•Warm, wet conditions, as can
occur with heavy dew or
overhead irrigation. Spores
survive in crop residues and are
spread by wind and irrigation
water.

32. Rust
Puccinia sorghi
•SYMPTOMS
•Elongated, reddish-brown
pustules appear scattered over
both the upper and lower leaf
surfaces. As these mature they
turn brownish black. Leaves
yellow and can become fragile.
•FAVOURED
•Warm (16–24° C) weather
combined with high humidity or
heavy dews. Spores are easily
spread by wind and can disperse
long distances. Some sweet
corn varieties are resistant to
common rust.

33. Rust
Polysora Puccinia polysora
•SYMPTOMS
• Oval, orange-brown
pustules up to 2 mm long
appear scattered over the
upper leaf surfaces. Spots
can also develop on the
stems and husks. As these
mature they turn brownish
black. Leaves yellow and can
become fragile.
•FAVOURED
•Warm to hot conditions
combined with high humidity,
Polysora can be
distinguished from common
rust by its lighter colour,
absence from lower leaf
surfaces and presence on
stems

34. Viral diseases
Johnsongrass mosaic
•SYMPTOMS
• Initially appears as small
yellow flecks in the young
leaves. These broaden and
expand with plant growth,
forming wide, pale yellow
stripes parallel with the
veins. Affected plants are
stunted and deformed.
•FAVOURED
• Although commonly found
in coastal areas, it is usually
a minor issue. The virus is
transmitted by the maize
planthopper

35. Disorders

36. Blanking
•SYMPTOMS
•Blank areas or unevenly sized
kernels occur on the cob. This can
be a particular problem on the tip of
the cob, which fails to develop
kernels.
•CAUSED
•Usually due to wet conditions or hot,
dry and windy weather during
pollination. Stress caused by too
much or too little water, nutrient
deficiencies or high night
temperatures (over 22° C) during
pollination and tip filling can also
cause blanking. Tip blanking can be
a varietal effect.

37. Boron deficiency
•SYMPTOMS
• Younger leaves are inrolled, erect
and brittle, developing pale yellow
streaks and mottled appearance.
Plants are shortened with stout,
oval stems. Boron affects silk
development and pollination, so
cobs are curved, small and/or have
blank areas.
•CAUSED
•Alkaline or strongly acid sandy
soils, particularly in cold weather or
very dry conditions.

38. Calcium deficiency
•SYMPTOMS
• New leaves develop pale, whitish
lesions that tear easily. In severe
cases the youngest leaves tend
to inroll with leaf tips remaining
joined to together, causing a ladder-
like appearance.
•CAUSED
• Most likely in acid (pH<5.0), sandy
soils or soils high in sodium,
magnesium or potassium.

39. Copper deficiency
•SYMPTOMS
• Younger leaves are yellowed as
they emerge. Leaves develop a
distorted, twisted habit and may
brown and crack along the edges.
Yellowing between
•the veins gives leaves a striped
appearance.
• CAUSED
•Most likely on acid (pH>7.5),
organic soils.

40. Iron deficiency
•SYMPTOMS
• Iron is immobile in the plant but is needed
for chlorophyll formation. Distinct and severe
yellowing between the veins therefore
develops in the youngest leaves. Plants
develop a striped appearance. Symptoms
are similar to manganese deficiency, but
chlorotic areas have a more distinct
boundary, with veins remaining green.
•CAUSED
•Insufficient iron available to the plant. Worst
in sandy soils with low organic
•matter or those with a high pH (>7). Iron
deficiencies are more likely in cool, damp
springs. Symptoms are worst on seedlings.

41. Magnesium deficiency
•SYMPTOMS
• Bright yellowing of the older leaves, initially between the veins. Yellowing starts from the leaf
tip and margins and spreads inward towards the central rib. This develops into a characteristic
reddening or browning, with only the central rib area remaining green and the leaf edges
becoming dry and papery.
•CAUSED
•Deficiency is most likely in acid, sandy soils. High levels
•of calcium and potassium in the soil can make magnesium unavailable to the plant.

42. Manganese deficiency
•SYMPTOMS
• Manganese is immobile in the plant but is needed for
chlorophyll formation. Yellowing between the veins
therefore occurs in the youngest leaves. Plants can
develop a striped appearance. Pale, streaky lesions may
occur in severe cases. Cobs are malformed, with poor or
uneven kernel development.
•CAUSED
•Deficiency is associated with pH>8, particularly in
chalky soils.

43. Nitrogen deficiency
•SYMPTOMS
• As nitrogen is mobile in the plant,
yellowing is initially observed in the
older leaves. Symptoms can then
spread to the whole plant, which
becomes pale and spindly. Older
leaves may die prematurely. Yellowing
tends to appear in a V-shape, starting
at the leaf tip and progressing down the
midrib to the leaf base.
•CAUSED
• Insufficient nitrogen is most likely in
cold, waterlogged soils lacking organic
matter. Heavy rain and high carbon
crop residues can remove nitrogen
from soils, especially from light, sandy
soils.

44. Phosphorus deficiency
•SYMPTOMS
• Older leaves develop reddish purple
leaf tips and margins. Occurs most
frequently in young seedlings, which
tend to be small with reduced vigour.
Older plants have a shallow root
system, silk emergence is delayed and
cobs have missing kernels.
•CAUSED
• Soils low in organic matter or high in
iron, which ties up phosphorus in a
less available form. Symptoms are
most likely in cold soils that are
excessively wet or dry.
•Note: seedlings of some varieties
develop purple colours even when
phosphorus is adequate.

45. Potassium deficiency
•SYMPTOMS
•Yellowing and then browning of the
older leaves starting at the leaf tip and
outer margin. Symptoms usually don’t
appear until at least a month after
planting. As the plant grows the lower
leaves yellow and die back from the
tip.
•CAUSED
•Heavy rain leaching potassium from
the soil, especially if early root growth
has been limited by dry or compacted
soil. Excess calcium and magnesium
reduce potassium availability.

46. Zinc deficiency
•SYMPTOMS
•A broad creamy white to translucent
band appears either side of the midrib,
starting at the bases of younger
leaves. Bleaching does not normally
extend as far as the leaf tip; the leaf
margins and midrib usually remain
green. Plants are stunted due to
shortened lengths between the leaf
nodes.
• CAUSED
•Usually occurs in soils with pH>7,
especially where soil is sandy or low in
organic matter due to removal of the
topsoil. High levels of soil phosphorus
reduce uptake of zinc.

47. Sulphur deficiency
•SYMPTOMS
•Younger leaves are pale to
yellowed. Yellowing may be
interveinal, or quite diffuse
across the leaf. Plants are
stunted with delayed maturity.
•CAUSED
•Most likely in sandy, acid soils
with low organic matter,
especially if conditions are cold
and dry after planting

48. Nutrition
•Sweet corn •papaya

49. Contact no. 8106056631