Weed dynamics in transplanted rice after intensification of rice-fallow cropping system in Jharkhand

A field experiment was initiated in 2006–07 at Kanke centre of AICRP on cropping systems. The present study was conducted to observe the effect of intensification of rice-fallow cropping system on weed dynamics in transplanted rice var. Lalat in 2008 and 2009 i.e. 4th and 5th year. Results showed that intensification of rice fallow cropping system at 300% cropping intensity considerably reduced the weed population and weed dry matter production as compared to 200% (rice-wheat) and 100% (rice-fallow) cropping systems. Among the cropping systems tested, rice - potato + wheat (1:1) - green gram recorded significantly lowest weed population and weed dry matter (at par with rice-potato-green gram). Intensification of rice-fallow was found to produce higher production and productivity of rice. Nevertheless, the yield differences were significant only in 2009 during which rice - potato - green gram recorded maximum rice grain yield being at par with the grain yield in rice - potato + wheat (1:1) - green gram. Effect of cropping system on harvest index of rice crop was also significantly higher at 300% intensification in rice - potato + wheat (1:1) - green gram and rice - potato - green gram over others