EFFECT OF PLOUGHPAN MANAGEMENT ON THE PERFORMANCE OF RICE VARIETIES UNDER DROUGHT PRONE RAINFED LOWLAND ENVIRONMENT

摘要

A field experiment was conducted at Alimganj (Madhupur Barind Clay Terrace Soil) to determine the effect of pioughpan manipulation on root growth, yield and nutrient uptake of rice. Four pioughpan manipulations (normal tillage 6-8 cm deep, reduced pioughpan through deep tillage 12-15 cm deep, reduced plough through deep tillage 18-20 cm deep and pioughpan perforation through Sesbania root penetration with normal tillage) were tested. Two promising BR lines (BR 4974-45-9-2 and BR 1870-88-1-1) and 3 rice varieties (BR11, BR25 and Beharibatraj) were used. Pioughpan starts from 9 cm soil depth and continued upto 17 cm. Therefore, the thickness of pan was about 8 cm. The experimental results show that reduced pioughpan through deep tillage and pioughpanperforation through Scsbania root penetration increased the rootmass density, grain and straw yield of rice over normal tillage, About 98% of root mass was confined within 10 cm soil layer in normal tillage. Reduced pioughpan through Sexbcmia root penetration decreased the soil penetration resistance and improved the nutrient uptake. The study suggests that deep tillage of growing deep rooting Sesbania is beneficial with respect to more rootmass distribution in the deeper soil layer and higher yield ofrice under drought prone minted lowland environment.