Effect of weed-management practices on yield and economics of sesame (Sesamum indicum)-based intercropping systems

The present investigation was conducted during the rainy (kharif) season of 2015 and 2016 at Kanpur, Uttar Pradesh, to study the effect of weed management on yield and economics of sesame (Sesamum indicum L.)- based intercropping system. The experiment comprising 12 treatments was laid out in a factorial randomized block design, replicated 4 times. Sesame + blackgram [Vigna mungo (L.) Hepper] intercropping system in 8 : 2 ra- tio (7.17) had the lowest weed population during both the years and on an average, recorded significantly lowest fresh (11.01) and dry weight (3.71) of weeds. The grain yield of sesame was found significantly in the sesame + blackgram (8 : 2) intercropping system during 2015 and 2016. The grain yield of maize (Zea mays L.) and blackgram was maximum in sesame + maize/blackgram under 8 : 2 row ratio and reduced drastically in intercrop- ping sesame + maize and blackgram under 4 : 1 ratio in the 2 years of study. The sesame-equivalent yield was significantly higher under intercropping of sesame + blackgram (8 : 2) over rest of the intercropping treatments. The sesame + blackgram (8 : 2) intercropping treatment was found significantly superior in terms of economics, viz. gross income ( 48.80 103/ha), net returns ( 26.82 103/ha) and benefit: cost ratio (2.22) on mean basis compared to the remaining intercropping systems, during both years. Among the weed-management practices, hand-weeding reduced the total weeds significantly compared to chemical weed-management practices, followed by alachlor (0.375 kg/ha) and pendimethalin (1.0 kg/ha) respectively. Significant reduction in fresh and dry weight of weeds/m2 was recorded with the hand-weeding. Among the chemical weed-management practices, alachlor treatment resulted in significantly lower fresh and dry-weight of weeds/m2 compared to pendimethalin treatment in both the years. The hand-weeding had a positive effect on grain of sesame with maize and blackgram, sesame equivalent yield, gross income, net income and B: C ratio, which was noted significant response over pendimethalin and alachlor weeding in both years of study. In chemical weed management, post-emergence appliciton of alachlor was found significantly superior over pre-emergence pendimethalin in the 2 years of study.