Response of groundnut (Arachis hypogaea) to biofertilizer, organic and inorganic sources of nutrient in North East India.

A field experiment was conducted during kharif seasons of 2005 and 2006 to study the effect of biofertilizer (s), organic and inorganic sources of nutrient supply on the yield of groundnut. Treatments consisted of four biofertilizers viz. control, Rhizobium , PSM and Rhizobium + PSM in main plots and seven nutrient combinations viz. control, lime @ 500 kg/ha (furrow application), FYM @ 10 t/ha, Lime + 50% NPK, FYM + 50% NPK, Lime + FYM + 50% NPK and recommended dose of NPK (20:60:40 kg/ha) in sub plots. Seed inoculation with Rhizobium + PSM significantly improved growth and yield of groundnut. Highest net return (Rs 22,755) and benefit cost ratio (1.49) was estimated with Rhizobium + PSM only. Application of Rhizobium or PSM improved residual nutrient status but marked improvement was observed with combined application of these biofertilizers. Application of Lime + FYM + 50% NPK increased growth, yield attributes, yield, available nutrient status, highest net returns (21,910 Rs/ha) and B:C ratio (1.23) over other nutrient levels. Integrated use of Lime + FYM + 50% NPK along with Rhizobium + PSM was the best for groundnut.