Influence of Plant Population and Herbicides on Performance of Black Gram and Weed Dynamics

Abstract

A field experiment was conducted to assess the Influence of plant population and herbicides on performance of black gram and weed dynamics, on sandy loam soil at Crop Research Centre, Chirori of Sardar Vallabhbhai Patel University of Agriculture & Technology, Meerut (U.P.), during summer season of 2018. The experiment was laid out in Split plot design with three replications. The main factor having three level of plant population maintaining by seed rates i.e. 20, 25 and 30 kg ha-1 and sub factor having five weed management practices i.e. Weedy check, Two hand weeding at 20 and 40 DAS, Quizalofop-ethyl 50 g a.i ha-1PoE at 30 DAS, Imazathapyr 100 g a.i. ha-1PoE at 30 DAS, and Pendimethalin 1.0 kg a.i. ha-1 P.E. was used as test variety. Study revealed that 20 kg seed rate ha-1(20% less plant population) provided the highest crop growth parameter than the other treatment. The maximum grain yield (12.20 q ha-1) was produced with 20 kg seed rate ha-1 which was significantly higher than the 25 and 30 kg seed rate ha-1 (11.35 and 10.48 q ha-1 . The higher net return (₹ 53740 ha-1) was also recorded with 20 kg seed rate ha-1 as compared to other treatment. The highest B: C ratio (3.39) was recorded with 20 kg seed rate ha-1 which was significantly higher than the other seed rate. The major weed flora in experimental field were Cyprus rotundus, Trianthama portulacstrum and Patrhenium hysterophorus along with some minor weeds i.e. Elusine indica and Amranthus viridis. On an average reduction in yield due to weeds infestation was recorded 52.7 % as compared to two hand weeding. The highest weed control efficiency (74.52) was recorded with the pre emergence application of Pendimethalin @1.0 kg a. i. ha-1. As far as weed management practices is concern, the chemical and mechanical method of weed control were found superior over weedy check. The lowest total weed population, lowest weed dry matter and highest grain (12.70 q ha-1) and straw yield (29.30 q ha-1) were recorded with treatment of two hand weeding. Among the herbicidal treatment Pendimethalin @ 1.0 kg a.i ha-1 found superior in respect to all parameter of crop growth and weeds, provided the highest grain (12.10 q ha-1), straw yield (29.03q ha-1), net return Rs. 50918) and B: C ratio (2.79) which was significantly higher than the other herbicidal treatments.