EFFECT OF POST-ANTHESIS CANOPY DEFOLIATION ON YIELD AND YIELD COMPONENTS OF WHEAT VARIETIES

Abstract

The experiment was conducted at the experimental site of Sher-e-Bangla Agricultural University (SAU) during the period from November 2016 to February 2017 to study the response of wheat varieties as influenced by different levels of leaf clipping treatment. The experiment comprised of two varieties viz., BARI Gom 26 (V ) and BARI Gom 30 (V ) and five different levels of leaf clipping viz., clipping of all leaves except flag leaf (L 2 1 ), clipping of flag leaf only (L ), clipping of all leaves except flag leaf & it’s immediate leaf (L 3 2 ), clipping of all leaves except flag leaf & first two leaves beneath flag leaf (L 4 ) and control/No clipping (L ). The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. Significant variation was recorded for plant height, number of tillers, effective tillers and non-effective tillers, stem dry weight, panicle dry weight, number of spikes, spikelet per spike and grain per spike. Moreover, 1000 seed weight, straw yield, grain yield and harvest index were also significantly influenced by varieties and/or leaf clipping treatments. Results demonstrated that BARI Gom 26 produced the maximum seed yield (1.53 t/ha). The control treatment (L 5 5 ) showed highest seed yield (1.742 t/ha). Among the ten treatment combinations, the variety BARI Gom 30 showed the best performance with maximum yield (1.833 t/ha) and harvest index (54.51 %) when remained unclipped and it can be recommended for further trial. Moreover, results described that L 1 , L 2 , L 3 and L treatments caused reduction in seed yield of BARI Gom 30 by 32.89%, 21.27%, 30.00% and 23.07%, respectively. Moreover, seed yield of BARI Gom 26 was also decreased by 12.5%, 10.12% and 17.39% with the application of L 1 , L 3 and L 4 4 , respectively.