Yield of Blackgram as Influenced by Residual Effects of Crop Establishment Methods and Weed Management Practices in Rice

The performance of rice fallow black gram is strongly influenced by prevailing soil conditions and the residual effects of weed management practices adopted in the preceding rice crop. Herbicide residues and changes in soil properties resulting from different rice establishment methods can influence the germination, growth and yield of the succeeding black gram crop. The impacts of weed management techniques and rice crop establishment techniques on crop performance and weed control effectiveness on the subsequent black gram were assessed in this study.

The study was conducted at Tamil Nadu Rice Research Institute, Tamil Nadu Agricultural University, Aduthurai (1101N, 7948E, 19.5 MSL.), Tamil Nadu, India. Three techniques for rice establishment were used in the split-plot design of the field trial, viz, dry directseeded rice, drum seeding and non-puddled transplanted rice (NPTR)-as main plots and seven weed management practices as subplots. In addition to the growth and yield characteristics of the subsequent black gram, weed dry weight and weed control efficiency (WCE) were measured at 60 DAS. Each treatment’s crop was collected and threshed independently and the yield for each plot was measured.

The results showed that weed dry weight and WCE were significantly affected by rice establishment techniques and weed control strategies. Among establishment methods, NPTR recorded lower weed dry weight and higher WCE compared to dry direct seeding. The maximum black gram seed yield was attained under pendimethalin followed by Florpyrauxifen-benzyl + cyhalofopbutyl, indicating the absence of adverse residual effects of herbicides, whereas the weedy check resulted in poor growth and yield. The study concluded that non-puddled transplanted rice (NPTR) combined with integrated herbicide-based weed management is an efficient and sustainable option for effective weed control in rice and enhanced productivity of rice fallow black gram.