Effect of Flag Leaf Clipping on Growth, Yield and Yield Attributes of Hybrid Rice in Boro Season

摘要

The experiment was carried out at the Experimental Field of Agricultural Botany Department, Sher-e-Bangla Agricultural University, Dhaka-1207, Bangladesh, during October, 2017 to May, 2018 to study rice varieties (viz. BRRI Hybriddhan1, BRRI hybrid dhan2, Heera2, Heera4, Nobin and Moyna) were used for this study. The experiment was laid out in Split-plot Design with three replications. All the test varieties exhibited superiority in control condition. The tallest plant (115.2) was recorded from Moyna at harvest effect of flag leaf clipping on growth yield, and yield attributes of hybrid rice varieties in Boro season. Six hybrid stage and higher individual flag leaf area (81.61cm~2) was observed from Heera4. Penultimate leaf area and third leaf area (78.98 cm~2 and 46.95cm~2, respectively) were obtained from BARIhybriddhan2. The highest number of leaves (67.33) and spikelet panicle~(-1) (219) were observed from Heera4. Among test rice varieties, higher grain yield (6.01tha~(-1)) and biological yield (13.45 tha~(-1)) were also achieved from Heera4. Days to maturity was significantly varied from 123 (Nobin) to 145 (BRRI Hybriddhan~1) among the studied varieties. Chlorophyll content (SPAD value) in penultimate leaf after 15 days after heading, grain filling duration, yield contributing characters and yield were investigated after cutting of flag leaf. Regardless of variety, all the studied parameters were exhibited superiority in control treatment. Chlorophyll and nitrogen content (SPAD value) in penultimate (1.35% to 17.27%) and grain filling duration were increased (4.5 to 6.25 days) by virtue of clipping of flag leaf. The highest number of effective tillers hill~(-1), filled grains panicle~(-1), weight of 1000 grains, grain yield, straw yield, biological yield were recorded from Heera4 under control condition. The clipping of the flag leaf reduced grain yield from 15.69% to 29.43% in the test Boro rice varieties.