Vol. 14 No. 1
Development of optimized source-sink relationship, favourable morpho-physiological behaviour and profitability of soybean through detopping and mepiquat chloride application
Author(s): M. JAIDKA, J. S. DEOL AND A. S. BRAR
Abstract: The influence of detopping and mepiquat chloride on the morpho-physiological and yield attributes of soybean was studied during kharif 2014 and 2015. The investigation was conducted at Punjab Agricultural University, Ludhiana which was laid out in RCBD design with eight treatments viz. control, detopping (50-55 DAS), MC @ 200 ppm (50-55 DAS), MC @ 200 ppm (50- 55 + 65-70 DAS), MC 250 ppm (50-55 DAS), MC @ 250 ppm (50-55 + 65-70 DAS), MC @ 300 ppm (50-55 DAS) and MC @ 300 ppm (50-55 + 65-70 DAS) with four replications. Detopping significantly decreased plant height, increased total dry matter accumulation plant-1, flowers and pods plant-1, pod setting percentage and seed yield over control. Mepiquat chloride significantly decreased LAI, abscission of reproductive parts, increased total dry matter accumulation plant-1, pods plant-1, 100- seed weight and seed yield over control. At harvest, an optimum source-sink relationship was developed in detopping and two foliar applications of mepiquat chloride @ 250 ppm by causing partitioning of total dry matter among stem, foliage and pods by 21.6, 17.4, 61.0 and 20.1, 9.2, 70.8 per cent, respectively, which led to increased yield levels (17.90 and 18.05 q ha-1) . Detopping and foliar applications of mepiquat chloride resulted in significant enhancement in the growth indices like CGR, RGR and NAR.