Direct and residual effects of organic and inorganic sources of nutrients under urdbean (Vigna mungo)-wheat (Triticum aestivum) cropping sequence in foot-hills of Uttaranchal

A field experiment was'tdmducted during 2002-03 to 2003-04 at Pantnagar, to study~the direct and residual effects of organic and inorganic sources of nutrients under urdbean [Vigna mungo (L.) Hepperl-wheat (Triticum aestivum L. emend. Fiori & Paol.) cropping sequence. Plant height in urdbean varied significantly with the appli- cation of farmyard manure @ 5 tonnestha and phosphorus @ 40 kg P,O,/ha over their respective control. Farm- yard manure @ 5 tonneslha also resulted in significantly higher number of podstplant, grain and biological yields than no-farmyard manure application. However 20 and 40 kg P,O$ha,being at par, recorded significantly higher grain yield than the control. Yield attributes, yield and harvest index in wheat were not influenced by im- proved because the residual effect of farmyard manure and phosphorus applied to urdbean, whereas 75 and 100% of recommended level, being at par, resulted in significantly higher values of yield attributes and yield compared to 50% of recommended level. On economic point of view, 75% of recommended fertilizer level re- sulted in the highest net return and also gave at par wheat-grain-equivalent yield to 100% of recommended level. Total nutrient uptake of the system and soil-nutrient status after urdbean-wheat sequence also increased significantly because of the direct and residual sources of nurients.