Evaluation of the relative weed competitiveness ability in upland rice cultivars

Weed management in rice production is a major constrain leading to low yields. Studies were conducted to assess the competitiveness of different rice varieties and to identify rice genotypes for weed competitiveness. The results showed varietal differences in their competitiveness against weeds. The presence of weed overall reduced the yield level from 172.6–1024.3g and 52.6–223.3g in weedy and weed free conditions, respectively. In weedy environment, grain yield showed positive and significant association with panicle length and number of filled grains per plant. The two genotypes identified to be exhibiting weed competitiveness were R 1033-968-2-1 and Kakro.