Low Cost Zero Till in situ Green Manuring for Faster Decomposition of Rice/Wheat Stubbles Left after Combined Harvest to Minimse Field Burning

Abstract

Low cost zero till in situ green manuring using different plant species i.e, dhaincha, sunnhemp, rice bean, jute, chocolate weed, khersai, white sweet clover, mustard etc., will eliminate the age old problems of large scale adoption of green manuring across the farming community. It will produce green manure at affordable price for rice, help in quicker decomposition of rice straw and minimise its field burning left after combined harvest (3.5- 6 t/ha), sequester enough carbon to the soil, minimise environmental pollution, improve soil health, soil structure and its water holding capacity. Rice bean, green gram, sunnhemp and, jute etc can also be grown as green manures/easily decomposable biomass resources after wheat harvest which can be mixed with its stubble under in situ condition for its quicker decomposition rather burning the later in open field creating environmental pollution. These different succulent species could successfully geminate after/before rice harvest under zero till condition and has the scope of green manuring at lower cost. Legumes will add 50 to 60 kg nitrogen per hectare along with a biomass of 10 - 30 t/ha. Adding dhaincha as green manure before kharif rice, its nitrogen requirement from chemical fertiliser was eliminated and it produced 39 q raw rice (cv. CR-1009)/ha at Bhubaneswar, Odisha. Non legumes like jute, mustard and chocolate weed produced succulent biomass of 8-10 t/ha at 30-40 days. Jute as green manure alone before rice produced 2.6 t rice grain /ha, where no chemical fertiliser was applied.