Effect of weed management practices on the performance of 4 rice cv. Nizershail

An experiment was carried out at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during the period from July to December 2018 to study the effect of weed management practices on the performance of rice cv. Nizershail. The experiment included five weeding treatments i.e., (i) no weeding (T0), (ii) hand weeding at 15 and 35 days after transplanting (DAT) (T1), (iii) application of pre-emergence herbicide (T2), (iv) application of early post-emergence herbicide (T3), and (v) application of post-emergence herbicide (T4). The experiment was laid out in a random- ized complete block design (RCBD) with three replications. All plant and yield contributing characters (except 1000-grain weight), and yields were significantly affected by weed control approaches. The application of early post-emergence herbicide Super power 10WP (T3) showed the promising results in controlling weeds in Nizershail rice. The highest values for plant height, panicle length and grain yield (1.41 t ha−1) were obtained from apply- ing post-emergence herbicide Super power 10WP. However, application of pre-emergence herbicide (Glycel 48SL) and two hand weeding at 15 and 35 DATs gave statistically similar grain yield. The results of the study showed that fifteen weed species belonging to six families infested the experimental plots. Weed density and dry matter were significantly affected by weed con- trol methods. Weed density and dry weight were also significantly affected by weed control methods. Both early post-emergence and post-emergence herbicides could effectively control the weed density and biomass.