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Model
Farming
RECOMMENDATIONS
for Better Cotton Crop Management.
Based on the research work of Central Cotton Research
Institute, Multan.
The following recommendations, if adopted, will help to
improve the yield per hectare
1. Crop Management
Practices:
- The key to successful cotton production
particularly with respect to leaf curl virus or any other adversity is the
adoption of better crop management strategy. The agronomic practices and
proper plant protection practices are the key factors to ensure good seed
cotton yield.
- Plant, virus resistant varieties viz.,
CIM-1100, CIM-448, CIM-443, CIM-446, CIM-482, FH-900, BH-18, FVH-53 and FH-634
as safe guard against yield losses caused by this disease.
- Soils where normal growth of the plant is not
expected, must be chiseled or deep ploughed.
- Green manuring practice is essential for more
productivity. The crops grown for this purpose should be buried in the soil
when they are tender and well before planting cotton for their
decomposition.
- The cotton should be planted on bed and furrows
for better yield. This practice of cultivation will improve irrigation
efficiency. Plant spacing in this method may be kept 6" - 9".
- The sowing time of cotton crop for Multan,
Bahawalpur and D.G. Khan Divisions is from 1st May to 20th of June. For
Faisalabad and Lahore Divisions from 1st May to end of May.
- Apply double pre-planting irrigation (Rauni) of
10 cm. depth each in "Fallow" and after Wheat.
- Thinning of the crop at appropriate time is
very important so that plant can regulate its growth according to the space
available. Space the plants within the row keeping in view variety, time of
planting, expected plant growth and fertility of the soil. While thinning,
uproot the weak and diseased plants to keep recommended plant population of
each variety.
- The plant spacing on flat sowing of CIM-1100,
FVH-53 and FH-634 should be 12" and first irrigation be given after 50-60 days
of planting.
- CIM-448, CIM-446 and CIM-482 should have plant
spacing of 9" and first irrigation be given 35-45 days after planting.
- Apply first irrigation 30 days after sowing to
early maturing varieties (CIM-240,
CIM-443, CIM-109, NIAB-78) and 40-45 days to medium maturing varieties
(MNH-147, BH-36, SLS-1, MNH-93). Avoid water stress during squaring, flowering
and boll formation.
- Keep the cotton fields free of weeds till the
crop makes canopy.
- Last irrigation to cotton must be stopped by
5th-15th October to avoid delay in crop maturity and late season pest
attack.
- Add 50 kg P2O5 per hectare to soils showing
available phosphorus test less than 10 ppm. If
possible, mixing of phosphate with farm yard manure in 1:2 ratio could improve
its efficiency.
- Nitrogen is the most limiting factor in
cotton production and may be
applied 75-150 kg N per hectare in split three
doses. The application may be completed by the time the crop makes canopy.
Excessive nitrogen delays crop maturity and increases pest attack.
- Fertigation (Fertilizer solution dripping into
irrigation water) method of application of nitrogenous fertilizer is inferior
to direct soil application method. It results in loss and uneven distribution
of fertilizer in the field.
- Fertigation (Fertilizer solution dripping into
irrigation water) could be applied at the time of canopy closure. Fertilizer
solution may be injected in irrigation water after 15-20 minutes of free water
flow.
- The crops showing deficiency of Nitrogen late
in the season can be sprayed with urea solution @ 3% concentration. This
solution should not be mixed with insecticides
- Sulphar and Boran may be added at the rate of
50-100 kg gypsum/ha and 2 kg Boran/ha respectively if deficiency of these
elements is discovered.
2. Weed Control
- Stomp 330E, Treflan and Orifan 480 EC @ 1
- 1.25 lt./acre may be used as pre-emergence herbicides for the control of
weeds specially 'It-sit' (Trianthema monogyna).
- Post-emergence herbicides Staple @ 33-40
gms./acre can be used safely without guard/shield when the weed seedlings are
3-5 cm in height gives good weed control.
3. Insect Pest
Control
- Excessive use of irrigation and nitrogen
encourages the attack of Helicoverpa armigera (American Bollworm) and sucking
pests, which must be avoided.
- The best control of Helicoverpa is on eggs
scouting. Spraying at red egg stage or newly hatched larvae gives excellent
control of Helicoverpa sp.
- Since Helicoverpa armigera lays most of the
eggs on the upper canopy of the plant, therefore, the insecticidal sprays
should especially be directed at the top portion of the cotton plant.
- The effective insecticides should be used and
rotated during the season to avoid the development of resistance.
- Effective insecticides should be used for the
control of H.armigera and avoid more than one sprays of any one chemical grou.
In case the ULV formulations are to be used, add cooking oil and sprayed a
volume should not be less than 3.7 lit/ha. Oil helps in the uniform
destribution of pesticides and increase the effectiveness of the
chemical.
- The selection of pesticides is extremely
important to control and reduce the resurgence of whitefly. Methamedophos
should not be used more than once in the season, because whitefly has
developed resistance against this insecticide. It has been confirmed that
Pyrethroids help in resurgence of whitefly. The Pyrethroid alone or in
combination with organophosphate should not be used before mid-August, to
check the flare up of whiteflies, aphids and spider mites.
- For effective control of whitefly, spraying
should be done at least an hour before sun rise when the whitefly is most
active. Any spray after two hours of sun rise may give poor control of
whiteflies.
- ULV formulations should be avoided against
whitefly. It has been found that after continuous spray of ULV formulations,
whitefly and aphids resurge in good numbers. In case the ULV formulations are
to be used then total volume of the insecticide with cooking oil is to be made
upto 1.5 litre/acre. Addition of oil helps in uniform distribution of
pesticides and increases the effectiveness of the compound in killing
pests.
- If aphids appear very late in the season,
spray should be avoided and predators be allowed to exercise control of this
pest.
4. Disease Control
a) Leaf Curl Virus
Based on the research findings at Central Cotton
Research Institute, Multan the management strategies recommended for the
control of this disease are as follows:-
- Resistant varieties such as CIM-1100, CIM-448,
CIM-443, CIM-446, FVH-53 CIM-482, FH-900, BH-118 and FH-634 should be
planted.
- It is always advisable to plant more than one
variety so as to create genetic barrier.
- Previous year's cotton stubs should be removed
from the fields because sprouts from diseased plant stubs are the source for
transmission of this disease.
- The seed treatment with systemic insecticide
can help to control the vector (whitefly)
- Plants are susceptible in their early growth
period. As soon as whitefly population and disease symptoms start appearing,
spraying regime based on the economic threshold may be planned for the control
of whitefly.
- Judicious use of fertilizer and irrigation is
the most important to manage the disease.
- The crop may also be protected from other
sucking pests as well.
- Weeds in and around cotton fields must be
eradicated
- Planting of cotton in the orchards may be
avoided.
- It has been observed that the tolerant
varieties, if attacked early in the season, have the ability to recover from
CLCV effects. The farmers are advised not to plough such fields but to adopt
recommended practices of cultivation to harvest reasonable yield of seed
cotton.
b)
Boll Rot
- Benlate @ 200 gms/acre or Liro Manzeb @ 600-800
gms/acre should be sprayed before plant canopy to control boll rot of cotton.
The lower portion of the cotton plant should be thoroughly sprayed.
- It has also been observed that the farmers
confused the symptoms of attack of thrips as virus attack and ploughed up
their fields. The cotton crop will recover from the thrips attack without
affecting the cotton yield whereas the leaf curl virus symptoms appear at
least 20-25 days after planting and the thickening of the veins shows the
presence of leaf curl virus.
- Excessive irrigation and nitrogen fertilizer be
avoided
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