Skip to content

Conservation agriculture in the rice-wheat system Photo: atharv patel · Pexels License · source ↗

Conservation agriculture in the rice-wheat system

The Indo-Gangetic Plain (IGP) rice-wheat system covers about 10.5 million hectares across Punjab, Haryana, Western UP, Bihar and Terai districts. After 50 years of intensive tillage and residue burning the system shows declining yields, falling water tables, poor soil organic carbon and rising air pollution. Conservation agriculture (CA) is the package of three practices — zero tillage, surface residue retention and crop diversification — that ICAR-IIWBR Karnal, ICAR-CSSRI, PAU Ludhiana and CCS HAU Hisar are promoting to fix these problems.

The three principles

  1. Zero or minimum tillage — drill the wheat seed directly into the standing or anchored rice stubble using a Happy Seeder or Turbo Seeder. Skips 4-6 tillage passes; saves 60-70 litres of diesel per hectare.
  2. Permanent surface residue cover — keep at least 5-7 tonnes of paddy residue per hectare on the surface. Acts as mulch, suppresses weeds, conserves moisture, reduces soil temperature in March, builds soil organic carbon.
  3. Crop diversification — break the rice-wheat monoculture with summer mungbean, autumn maize, mustard or pulses on a 3-year rotation.

Implementation

A typical CA rice-wheat package is: rice harvested in late October to early November with a Super Straw Management System (Super SMS) fitted on the combine, chopping and spreading straw; wheat drilled directly with Happy Seeder 5-15 days after rice harvest; pre-emergence pendimethalin 1 kg/ha sprayed; nutrient package NPK 150:60:40 kg/ha with N split 50-25-25; first irrigation at 20-25 DAS rather than the usual 35 DAS to wet the residue and start decomposition.

Benefits documented in IGP

ICAR long-term trials at Karnal, Modipuram and Ludhiana show: 8-12 percent wheat yield gain (where residue is managed properly), 25-30 percent water saving, 30-40 percent fuel saving, 78 percent reduction in greenhouse gas footprint from avoided burning, 0.1-0.2 percent soil organic carbon gain over 5-7 years, and reduced Phalaris minor (mandusi) weed pressure once the system stabilises.

Limitations

CA needs a Happy Seeder or Turbo Seeder (Rs 1.6-2.5 lakh) — most small farmers access it through custom-hiring or FPO cooperatives. The first 1-2 years can show small yield drops while soil biology adjusts. Residue management has to be uniform — patchy residue gives uneven germination. Herbicide resistance management in Phalaris needs rotation of clodinafop, pinoxaden, sulfosulfuron rather than one product alone.

See also: Happy Seeder for paddy residue, Wheat irrigation stages, In-situ residue decomposition, Wheat crop in Telangana.

Sources

  1. Conservation Agriculture in Rice-Wheat. ICAR-IIWBR Karnal.
  2. Resource Conservation Technologies for Sustainable Rice-Wheat. ICAR.