Effect of Pre and Early Post Emergence Herbicides on Weed Control in Irrigated Blackgram (Vigna mungo L.)

摘要

Field experiment was conducted to find out the effect of pre-emergence (PE) and early post-emergence (EPoE) herbicides on weed control in irrigated blackgram at College of Agricultural Technology, Kullapuram- Theni during 2015-2016. In this experiment, weed management practice of preemergence application of Pendimethalin 30 EC 1.0 kg a.i. ha~(-1) at 3 days after sowing (DAS), early post-emergence application of Quizalofop ethyl@ 50 g a.i. ha~(-1) at 15 DAS, early post-emergence and Imazethapyr each @50 g a.i. ha~(-1) at 15 DAS and their combinations of Pendimethalin @ 1.0 kg ha~(-1) at 3 DAS followed by either Quizalofop ethyl or Imazethapyr each @ 50 g a.i. ha~(-1) were tested against hand weeding twice at 20 and 40 DAS,1 weedy check and weed-free check as controls in randomized block design replicated thrice. Among the different weed management practices, preemergence application of Pendimethalin 1.0 kg a.i. ha~(-1) (3 DAS) followed by Imazethapyr @ 50g a.i. ha~(-1) asEPoE (15 DAS) recorded relatively lesser proportion of broad-leaved weeds (30.90 and 49.16%) and higher Weed Control Efficiency (WCE) of 91.27 at 60 DAS. Application of pendimethalin1.0kg a.i. ha~(-1) PE (3 DAS) followed by Imazethapyr @ 50g a.i. ha~(-1) as EPoE (15 DAS) registered significantly taller plants (42.22 cm), higher dry matter production(2649 kg ha~(-1)), more number of pods per plant (44.19), seeds per pod(5.57) and higher grain yield (1052 kg ha~(-1)). Thus, pre-emergence application of pendimethalin 1.0 kg a.i. ha~(-1) (3DAS) followed by Imazethapyr @ 50g a.i. ha~(-1) as EPoE (15DAS) recommended as effective and economic weed management practices on the basis of better weed control, crop growth, and yield of irrigated blackgram.