DRY MATTER ALLOCATION AND GRAIN YIELD OF WHEAT AS INFLUENCED BY SOLAR RADIATION LEVEL AND PLANT DENSITY

Abstract
An experiment was conducted from November 2018 to March 2019 to identify the effect of radiation levels and plant population on dry matter allocation and yield of wheat with the variety ‘BARI Gom 25’. The study was set out in the Randomized Complete Block Design with four radiation levels (full sunlight, 75% light, 55% light and 25% light) and three plant densities (160 plants m-2, 200 plants m-2, 230 plants m-2) that replicated thrice. Full sunlight or 75% light in combination with optimal plant density (200 plants m-2) resulted maximum culm dry weight, leaf dry weight, spike dry weight and total dry matter weight plant-1. The numbers of filled grain and unfilled grain plant-1 and yields of grain and straw m-2 were the highest from the above-mentioned combination. The lowest dry weights for culm, leaf, spike, and total dry matter and minimum grain yield and straw yield were obtained from 25% light either alone or in combination with any plant densities indicating the profound influence of light on dry matter production and grain yield of wheat. Therefore, reduced light (up to 25%) and optimal plant density can ensure wheat production without significant yield loss. This finding suggests possibility of wheat cultivation in agroforestry system and light limiting areas in Bangladesh and other parts of the world.