Introduction
The cotton crop is an important crop in Punjab State. It was grown on 509 thousand hectares in 2004 – 2005. The total production was 2087 thousand bales. The average lint yield for the state as a whole was 697 kg per hectare.
Climatic requirements for growing Cotton
A daily minimum temperature of 16 degrees C is required for germination and 21 degrees C to 27 degrees C for proper crop growth. During the fruiting phase, the day temperature ranging from 27 degrees C to 32 degrees C and cool nights are needed. The cotton – picking period from mid – September to November must have bright sunny days to ensure a good quality of the produce.
Soil Type
Cotton crop can be successfully grown on all soils except sandy, saline or waterlogged types. Proper drainage of excess water during rains is essential.
Rotations
1. Cotton – Fallow
2. Cotton – Wheat / Barley
3. Cotton – Sunflower
4. Cotton – Senji / Barseem / Oats
5. Cotton – Sunflower – Paddy – Wheat
Agronomic Practices for Cotton cultivation
Land Preparation
A fine seedbed is essential for securing good plant stand.
Cotton Varieties/hybrids | Seed rate (kg/acre) | |
American Cotton | ||
Hybrids : | LHH 144, Ankur 651 and Whitegold | 1.5 |
Varieties : | F 1861, F 1378, F 846 and LH 1556 | 3.5 |
Desi Cotton | ||
Hybrids : | Moti | 1.25 |
Varieties : | LD 694 and LD 327 | 3.0 |
Acid Delinting of Cotton Seed
Mix 400 g commercial grade concentrated sulphuric acid with 4 kg cotton seed for American cotton and mix 300 g commercial grade of sulphuric acid with 3 kg seed of desi cotton in either / plastic container by stirring it vigorously for two to three minutes with a thick wooden or glass rod. As soon as the fuzz gets dissolved, add 10 litres of water, stir well and drain out water through the perforated plastic basket.
Repeat these washings three times to make the seed free from sulphuric acid residue. Dip the washed seed for about one minute in sodium bicarbonate solution (50g sodium bicarbonate in 10 litres of water) to neutralize the acid residue on the cotton – seed. Give one more washing with water and remove light, damaged and rotten inviable seeds floating on the surface. Dry the healthy fuzz free seed in the shade by spreading in a thin layer. Treat the dry seed with recommended fungicides.
Precautions
- Metal or wood container should not be used.
- The operator should wear plastic gloves
- The water containing acid and alkali residue should be properly disposed of in the wasteland.
- Inadequate washing and delayed washing of the seed after acid treatment and residual acid on the seed if not neutralized may impair the germination of seed.
Seed Treatment
Add half a gram (0.5 g) Emisan – 6 and one-fourth gram (0.25 g) of Streptocycline for one kg cotton seed in one litre of water. In case of acid delinted seed soak the seed for 2 – 4 hours and for non – delinted seed 6 – 8 hours. Also add half g succinic acid in 5 litres of water to promote the good establishment of plant stand, better early growth, and more yield. After this treatment, the cotton seed should be smeared with Gaucho 70 WS (Imidacloprid) @ 5 g/kg seed for preventing damage by cotton jassid.
In case undelinted seed is used, rub it with fine earth, cow dung or ash to remove its fuzz and ensure its uniform distribution.
Time of Sowing
Whole of April
Note: Sowing during this period ensures better yield and escapes the attack of insect pests and diseases.
Sowing and Spacing for Cotton
Sow in lines 67.5 cm apart with a cotton sowing drill. The plants within rows be kept 60 cm apart at thinning in case of narma and 45 cm in case of desi cotton. However, for hybrid LHH 144, Ankur 651 and Whitegold plant to plant distance should be kept at 75 cm. It may be done after first irrigation or heavy showers. For Moti Hybrid the plant to plant spacing should be kept at 60 cm.
Ridge Sowing
Sowing of cotton on ridges prepared with cotton planter and irrigating the crop planter and irrigating the crop in furrows saves a considerable amount of irrigation water without a reduction in seed cotton yield.
Weed Control in Cotton
Hoe two or three times. The first hoeing should be done before first irrigation. For hand weeding, use of a wheel hoe is recommended. A tractor-drawn cultivator or bullock driven Triphali can also be used in the early stages of the crop growth but their use after fruit initiation should be avoided. Chemical weed control in cotton is cheap and efficient.
For control of weeds particularly its it (Trianthema portulacastrum), Madhana / Makra (Eleusine spp), apply Treflan 48 EC, Shaktiman Triflurex 48 EC (trifluralin) @ 1.0 litre / acre on a well prepared seedbed and incorporate these herbicides thoroughly in 3 – 4 cm soil or stomp 30 EC @ 1.0 litre / acre as pre-emergence within 24 hours of sowing. Weeds start emerging at about 5 – 6 weeks after application of herbicide. Give one hoeing / interculture around 45 days after sowing to control these weeds.
Alternatively, in place of hoeing / interculture apply Gramoxone 24 percent WSC (paraquat) 500 ml / acre or Roundup 41% SL / Glycel 41% SL (Glyphosate) 1.0 litre / acre in 100 litres of water (6 – 8 weeks ) after sowing when the crop is about 40 – 45 cm in height as a directed spray to control weeds in – between the crop rows. To avoid drift, spray these herbicides on non – windy days. The directed spray can be done using knapsack sprayer fitted with flat fan nozzle and keeping the boom height low ( 15 – 20 cm above the ground level ) or using a protective hood so that herbicide does not fall on crop leaves. Both paraquat and glyphosate are non – selective herbicides and can cause injury to the crop if it falls on the crop leaves. However, falling of herbicides on the stem of the plant is not harmful.
In situations where perennial weeds are a problem, glyphosate is more effective and provides long duration control.
In situations where it is, it emerges after ‘first irrigation or with the rain shower Stomp @ 1.0 litre/acre can also be applied as post-emergence after first irrigation to cotton. If the weeds emerge before the application of the herbicide, a light hoeing/ inter-culture may be done as the Stomp does not control the emerged weeds. Dissolve the herbicide thoroughly in 200-250 litres of water/acre and spray it uniformly with a knapsack sprayer fitted with flat fan or flood jet nozzle. The herbicide can also be sprayed with tractor mounted sprayer fitted with a flat fan nozzle. For getting good results with the herbicide, following precautions should be taken:
– Prepare a fine seedbed free from plant residues and clods to ensure adequate moisture in the field at the time of spray of herbicide.
– A spray of the herbicide should be done either in the morning or evening hours
Fertilizer Application
Cotton responds well to the application of nitrogen. In certain areas, the crop shows some response to the application of phosphatic fertilizers.
Drill all phosphorus with the last ploughing. Apply half N at thinning and the remaining half at the appearance of the first flower for all varieties except LH 1556.
For LH 1556 the first half dose of N may be applied along with phosphorus at sowing and remaining half of N around mid-July. If the soil is low in fertility, the first half dose of N may be applied at sowing instead of at thinning. Apply 20 kg muriate of potash and 10 kg zinc sulphate per acre to cotton on light soils. To get higher yields, give four sprays of 2% potassium nitrate at weekly interval starting at flower initiation in addition to soil applied fertilizers.
The following fertilizer recommendations for Cotton
*Nutrients (kg/acre) | Fertilizers (kg/acre) | |||||
N | P2O5 | Urea (46% N) | DAP or (18% N 46% P2O5) | Super- Phosphate (16% P2O5) | ||
(A) | Varieties | 30 | 12 | 65 | 27 | 75 |
(B) | Hybrids | 60 | 12 | 130 | 27 | 75 |
* These nutrients can also be supplied from other fertilizers available in the market
** Where 27 kg DAP is used, reduce the urea dose 10 kg.
Note: Omit application of phosphorus to cotton when it follows wheat which received recommended dose of phosphorus.
Irrigation of Cotton crop
Cotton requires four to six irrigations, depending upon the seasonal rainfall. The first irrigation should be given 4 to 6 weeks after sowing and the subsequent ones at an interval of two or three weeks sowing cotton on ridges and irrigation in furrows save a considerable amount of water. The crop must not be allowed to suffer for want of water during the flowering and fruiting stages, otherwise a lot of shedding of flowers and bolls will take place resulting in low yield cotton during its early growth is very sensitive to water stagnation. Therefore, drain out the stagnant water, if such a situation arises. To hasten boll opening give the last irrigation by the end of September.
Caution
On light soils and in crop sown on ridges, the first irrigation may be advanced if necessary.
Hybrid Seed Production
LHH 144:
This is a cross between PIL 43 (Female parent) having okra lobed leaves and PIL 8 Miah (male parent). The hybrid seed is produced by hand emasculation of flower buds of female parent and pollination by flowers of male parent. The seed of parental lines should be purchased from Punjab Agricultural University every year to maintain genetic purity. The emasculated female bud is covered with soda straw pipe and the male flower is tied with a 3″ piece of a thread in the evening. The tied male flowers are used for pollinating the emasculated female buds in the morning. A piece of thread is tied to the stalk of the bud after pollination which serves as a marker for crossed boll.
Characteristics of Parents
PIL 43:
The female parent of LHH 144 has bushy plant habit with 3.4 monopods, okra type narrow lobed green leaves, creamy white flower, and pollen. It has bold seeds. It matures in about 185 days.
PIL 48:
The male parent of LHH 144 has compact plant type with 0 – 1 monopod and about 130 cm plant height. It has medium lobed green leaves, creamy white flowers and matures in about 165 days.
Isolation of hybrid seed plot:
The hybrid seed production field should have an isolation of 50 meters from other American cotton varieties and 5 meters between male and female plots to ensure the genetic purity of the seed.
Seed Rate and Spacing in Hybrid Seed Plot:
One acre hybrid seed production plot requires 6 Kanal area under the female parent and 2 Kanal area under male parent with the following seed rate and spacing
Parental lines | Seed rate (kg/acre) | Spacing (cm) LHH 144 |
Female | 3.0 | 67.5 * 90 |
Male | 1.5 | 67.5 * 60 |
The skipping of one row after every two rows in female plot gives the better setting of crossed bolls. In LHH 144 hybrid seed production 50 per cent of the male parent should be sown along with female parent and the remaining 50 per cent 10 – 15 days later to get a sufficient number of male flowers for crossing.
Roughing
Off-type plants based on plant colour, leaf shape, flower colour, etc., if any, should be rogued to maintain the purity of parental lines.
Seed Production Technique
The F1 hybrid seed is produced by the placement of functional pollen of the desired male parent onto the receptive stigma of the emasculated female at right time. Emasculation of flowers is done from 3 PM to 6 PM by removing the anthers with thumbnail before maturity (anthesis) and pollinate the next morning from 8 AM to 10 AM when stigma is receptive. Avoid too young or too old buds. The male flowers to be taken for pollination should be selfed the previous evening to avoid contamination by insects. For identification of crossed bolls at maturity, the crossed flower buds should be tagged in order to enhance the setting percentage unattempted flowers and naturally formed bolls should be removed. Hybrid seed plot should be kept free from weeds and special care should be taken to prevent damage due to insect pests and diseases.
Picking, Storing and Ginning
The kapas from crossed healthy and marked bolls should be picked, stored and ginned separately. The cleaned seed should be labeled and stored in a clean, dry place. It is genetic purity and germination should be tested before use.
Hybrid Seed Production
Moti: Desi Cotton Hybrid:
This hybrid is produced by crossing DS – 5 (female parent) with LD 210 (male parent). DS – 5 is a genetic male sterile line and, thus there is no need of emasculating the female flowers. The crossing is accomplished by applying pollen from freshly opened flowers of the male parent on the stigma of the freshly opened flowers of the female parent.
Maintenance of Parental lines
Female Parent (DS – 5):
The sterile male line is maintained by pollinating the male sterile plants with pollen from male fertile plants of the same line. Since male sterility DS – 5 is controlled by the as single recessive nuclear gene, so we always get a mixture of male sterile and male fertile plants in 1: 1 ratio.
The male sterile plants are identified on the basis of their small, whitish and shrivelled anthers. The male fertile plants have well-developed anthers and after flower opening, the anthers are covered with bright yellow pollen grains. Freshly opened flowers on male sterile plants are pollinated with pollen from male fertile plants in the morning (9.00 – 11.00 AM). Pollination is done by rubbing the anthers of fertile flowers in the stigma of male sterile flowers. For identification of cross these artificially pollinated flowers, a thread is tied to the pedicel of the flowers immediately after pollination.
Male Parent (LD 210):
This is a normal male fertile genotype. It is maintained just like other varieties by following normal seed production and certification norms. Care should be taken to maintain maximum genetic purity.
Characteristics of Parents
1.DS – 5
It is a generic male – sterile line. The male – sterile plants are identified by their small, shrivelled and whitish anthers. It has a green plant body with narrow, deep cut leaves, creamy white flowers, and monopodial plant habit.
2. LD 210
Green plant body with narrow lobbed deep cut leaves, white flowers, plant habit semi sympodial.
Production of hybrid seed
Isolation of hybrid seed plot:
The hybrid seed production plot should have an isolation of 50 meters from other desi cotton varieties and 5 meters between male and female plots to ensure genetic purity of the seed.
Seed rate and Spacing in hybrid seed plot:
One acre hybrid seed production plot requires 6 Kanal area under the female parent and 2 Kanal area under male parent with the following seed rate and spacing.
Parental lines | Seed rate (kg/acre) | Spacing (cm) |
DS-5 (Female Parent) | 2.0 | 67.5 × 45 |
LD 210 (Male Parent) | 1.0 | 67.5 × 45 |
The skipping of one row after every two rows in female plot gives the better setting of crossed bolls.
Roughing
In the female parent, 50% of plants are expected to be male – fertile. These plants are identified by examining the first opened flower and roughed out. This is necessary to obtain a pure stand of the male – sterile plants.
Crossing Procedure
For the production of hybrid seed, freshly opened flowers of the male parent (LD 210) are used as a source of pollen. Pollen is applied in the morning (9.00 – 11.00 AM) by rubbing anthers of the male flower on the stigma of freshly opened flowers of female parent (DS – 5). For identification of crossed bolls, threads are tied to the pedicel of cross-pollinated flowers. In order to enhance the set percentage, unpollinated flowers and naturally pollinated bolls should be removed. Hybrid seed plot should be kept free from weeds and special care should be taken to control insects and diseases. The crop should not suffer from moisture stress flowering stage as it will lead to the shedding of flowers/bolls.
Picking, Storing and Ginning:
The Kapas from crossed healthy and marked bolls should be picked, stored and ginned separately. The cleaned seed should be labelled and stored in a clean, dry place. It is genetic purity and germination should be tested before use.
Insects and Pests management of Cotton Crop
Disease management of Cotton Crop
Source-
Central Institute of Cotton Research-ICAR