INFLUENCE OF IRRIGATION AND NITROGEN ON GROWTH AND YIELD OF RAPESEED

Abstract

An experiment was conducted at the agronomy research field of Sher-e-Bangla Agricultural University. Dhaka during the period from October 2013 to February 2014 to evalute the influence of irrigation and nitrogen on yield of rapeseed (Brassica campestries). There were four different levels of irrigation viz., no irrigation, one irrigation at 25 days after sowing (DAS), two irrigations at 25 and 50 days after sowing (DAS) and three irrigations at 25, 50 and 70 days after sowing (DAS) and four levels of nitrogen viz., 0. 58, 115 kg N hi' and urea super granule (1.8 gm USO placed at 50 cm distance at 5 cm depth in the row) N hi'. The experiment was laid out in split plot design with 3 replication. Irrigation and nitrogen significantly influenced the growth, development, yield and yield attrihuters of rapeseed. Plant height, plant dry matter, branches plant'. siliqua length, seeds siliqua-', weight of 1000-seeds, seed yield, stover yield, biological yield and harvest index were significantly influenced by both irrigation and nitrogen. Among the irrigation treatments three irrigation-one at 25 DAS (preflowering stage), second at 50 DAS (siliquae formation stage) and another at 70 (seed maturation stage) resulted the better growth parameters like plant height, dry matter weight and the yield components like branches plani', siliquae planf'. siliqua length, seeds siliqua', 1000 seed weight, seed yield, stover yield, and harvest index. The highest seed yield (1589 kg hi') was obtained at three irrigations while control treatment gave the lowest yield (1095 kg hi') .me results revealed that, at the rate of 115 kg N hi' performed the best results in all respect. The highest seed yield (1712 kg ha') was obtained at 115 kg N hi' . The interaction effect of irrigation and nitrogen revealed that three irrigations one at 25 DAS (pre-flowering stage), second at 50 DAS (siliquae formation stage) and another at 70 DAS (seed maturation stage stage) in combination with 115 kg N ha gave highest yield (2065 kg ha') by producing highest yield contributing characters as well as other yield contributing characters