Effect of kharif greenmanuring and rabi tillage on physical properties of puddled clay loam under rice-wheat rotation

The effects of kharif greenmanuring and different rabi tillage operations on soil physical properties and rice-wheat yields were evaluated on clay loam soil (Typic Ustochrept). At 30 days after direct seeding of rice, bulk density of surface layer was significantly lower and root growth was more vigorous under greenmanure system (GM) than without greenmanure (WGM). Consequently at halvest, tillers and biomass and grain yield of rice under GM system were significantly higher than that under WGM system. In rabi, chisel and deep tillage systcms, reduced weed mass, lowered bulk density of surfate and subsurface soil and increascd hydraulic conductivity and infiltration rates, enhanced root growth and hence more wheat yield was obtained than that under minimum tillage system. Residual effect of greenmanuring on soil physical properties was apparent only during initial crop growth stage. Wheat grain yield under GM system did not differ much with that under WGM system in 1991–92 but was significantly higher than WGM system in 1992–93 after second consecutive application of ereenmanuring in kharif.