Popis: |
In South Asia, including Bangladesh, most farmers sow wheat under residual soil moisture after rice is harvested, but the upper layer of soil dries quickly after soil has been prepared for wheat sowing. Crop seeds that are sown either deeply or shallowly can result in failed emergence, low dry matter accumulation, and reduced grain yield. Therefore, appropriate sowing depth is crucial for seedling emergence and successful crop establishment. Considering this, a two-year field experiment was conducted at the research field of the Agricultural Research Station of the Bangladesh Agricultural Research Institute at Dinajpur during the dry, rabi (winter) season of 2013-14 and 2014-15, at four sowing depths, i.e., 2, 4, 6 and 8 cm, to identify the most appropriate sowing depth for higher grain yield. Wheat seeds sown at a depth of 4 cm resulted in significantly highest number of seedlings and seminal roots, tallest plants as well as largest roots and plant biomass followed by sowing at a depth of 6, or 2 cm. Depth of sowing also significantly affected the yield and yield-related attributes, all performing best at a depth of 4 cm. The highest number of spikes m-2, grain yield, straw yield and harvest index were observed when seeds were sown at depths of 4 or 6 cm, relative to 2 or 8 cm. Therefore, a sowing depth of 4 to 6 cm is recommended for wheat cultivation in South Asia, including Northern Bangladesh. |