Management practices discussed for irrigated and rainfed wheat are summerised as package of practices for wheat production.
Irrigated Wheat:
Tillage:
1. Well pulvarised but compact seedbed is necessary for uniform seed germination.
2. Two to three ploughings followed by a harrowing leads to an ideal seedbed.
3. In intensive cropping systems (rice-wheat, maize-wheat, cotton-wheat etc), zero tillage seed drills appear to be ideal.
Seeds and Seeding:
1. Seed treatment with Vitavex, Bavistin, or Thiram at 2.5 g kg-1 of seed.
2. Optimum time of sowing is second fortnight of November. Late sowing in intensive cropping systems can be up to the end of December.
3. Seed rate for timely sown crop is 100 kg ha-1 with a row spacing of 20.0 to 22.5 cm. For a late sown crop, seed rate is 125 kg ha-1 with a row spacing of 15 to 18 cm.
4. Depth of seeding is 5 to 6 cm for improved cultivars.
Fertiliser Schedule:
1. Apply 120-150 N, 40-60 P2 O5 and 40 K2 O ha-1 for timely sown wheat. For a late sown crop, recommended schedule is 80-100 N, 40-60 P2O5 and 20 K2O ha-1.
2. Phosphatic and potassic fertilisers should be applied at seeding by placement.
3. In medium to heavy soils, apply N in two equal splits at sowing and after first irrigation.
4. In case of light soils, apply N in three equal splits at sowing, after first irrigation and after second irrigation.
5. Application of 25 kg zinc sulphate ha-1 is sufficient to meet the Zn demands of rice as well as subsequent wheat crop, except in salt affected soils, which need 10 kg Zn ha-1 in rice crop.
Irrigation Schedules:
1. CRI, boot and milk stages are more sensitive to soil moister stress. Based on the availability of water, priority should be as per the sequence.
2. If irrigation water is not limiting, six irrigations at CRI, tiller completion, late jointing, flowering, milk and dough stages are adequate for optimum yield.
Weed Management:
1. First 30-40 DAS is critical for weed competition.
2. Broad leaved weeds can be managed with 2, 4-D (0.4 kg) 30 DAS.
3. Mixed population of narrow and broad leaved weeds can be managed with a mixture of Isopoturon and 2,4-D at recommended doses around 35 DAS.
4. Integrated weed management including thorough land preparation, manual weeding and herbicides can keep the weed growth under check for economic wheat production.
Rainfed Wheat:
Tillage:
1. Well pulvarised but compact seedbed is necessary for uniform seed germination.
2. Two to three summer ploughings followed by harrowing after each rain is adequate for checking wed growth and obtaining ideal tilth.
3. Deep ploughing once in two to three years is necessary to keep perennial weeds under check and conserving soil moisture.
4. If the land is kept fallow during rainy season, repeated harrowing is necessary to check the weed growth.
Seeds and Seeding:
1. Seed treatment with Vitavex, Bavistin, or Thiram at 2.5 g kg-1 of seed.
2. Optimum time of sowing is second fortnight of October in Peninsular zone and up to the end of November in relatively cooler zones
3. For Peninsular zone, seed rate is 120 kg ha-1 with a row spacing of 20 cm. For other zones, seed rate for timely sown crop is 100 kg ha-1 with a row spacing of 20 to 25 cm.
4. Depth of seeding is 6 to 7 cm for improved cultivars.
Fertiliser Schedule:
1. Apply about 20 t ha-1 of compost/FYM once in two to three years for improving water retentive capacity of the soil.
2. Recommended fertiliser schedule is 60 N and 20 P2 O5 kg ha-1.
3. All the NP fertiliser should be applied at seeding by placement/drilling.
Moisture Conservation:
1. Deep black soils are usually kept fallow during rainy season. To keep the soil weed free and absorb rainwater, it should be periodically harrowed till wheat seeding.
2. Repeated intercultivations to keep down the weed growth and to create soil mulch to minimise soil moisture loss by evaporation is necessary for optimum yields.
Weed Management:
1. First 30-40 DAS is critical for weed competition.
2. Thorough land preparation and repeated intercultivations (harrowing) can minimise the losses due to weeds.
3. Herbicides may be used where soil condition does not permit intercultivation.
4. Mixed population of narrow and broad leaved weeds can be managed with a mixture of Isopoturon and 2, 4-D at recommended doses around 35 DAS.
Harvesting and Storage:
Harvesting:
Wheat crop is harvested when the grain hardens and the straw turns light yellow, becomes dry and brittle at seed moisture content of 18-22 per cent. The rainfed (barani) crop reaches harvest stage much earlier than irrigated crop. The harvesting time varies from zone to zone.
Peninsular zone – Middle of February to first week of March
Central zone – February to March end
Northeastern zone – Third week of March to mid-April
Northwestern zone – Third week of April to first week of May
Hill zone – May-June.
High temperature shortens the growing period. If the crop does not ripen before the onset of hot westerly winds, shrivelling of grain take place.
Most of the harvesting in India is with the sickle. Bullock drawn reapers are also used occasionally. In recent years, harvesting is done in Punjab, western Uttar Pradesh, Delhi and Haryana with combiners on custom service basis. Harvesting, threshing and winnowing are completed in singe operation.
Manually harvested crop is, generally, dried for 3-4 days and threshed by treading with cattle on threshing floor. Use of stoneroller, saw-thresher, tractor etc. expedites the operation. Generally, winnowing is by winnowing baskets. Simple mechanical threshers have become popular in northeastern and northwestern zones.
Yield:
The yield varies with the duration of the variety and length of crop growing period besides several other management practices. The yields under rainfed conditions are generally low. It may be as low as 300 to 400 kg ha-1 in Peninsular and central zones.
Under irrigated conditions, yields as high as 10 to 12 t ha-1 have been reported, where as in the National Demonstrations, yield up to 8.0 t ha-1 were reported. A grain yield of 4.0 to 5.0 t ha-1 of dwarf wheat has become a common feature at farmer’s field in the major wheat zones. However, the national average during 1999 was 2.8 t ha-1.
Information gathered by wheat project indicates that Punjab has potential of 7.5 t ha-1 and northwestern plain zone around 7.01 ha-1 indicating a big gap between the potential and actual yield obtained by fanners. Results of Front-Line Demonstrations indicated yield gap of 1.0 t ha-1 in northeastern plain zone between front-line trials and experimental farms.
What straw is an important cattle feed in India. Generally, straw yield of rainfed wheat is about the same as that of grain, whereas from irrigated crop it is about 1.5 to 2.0 times the grain yield. Straw yield of dwarf wheats is less than that from the traditional tall varieties.
Storage:
Wheat harvested at more than 12.5 per cent grain moisture should be dried to less than 12.5 per cent within 3-5 days to prevent growth of molds and damage by storage pests. Heat must be added in areas of high humidity and airflow rate must be adjusted.
At 85 per cent relative humidity, wheat will equilibrate around 18.5 per cent moisture but air alone at RH of 60 per cent will dry wheat to around 12 per cent moisture over time. Storage facilities depend on the economic factor. Easy and cost effective storage methods used by resource poor farmers include metallic bins, gunny bags and earthen pots.