Effect of Cobalt, Rhizobium and Phosphobacterium Inoculations on Growth, Yield, Quality and Nutrient Uptake of Summer Groundnut (Arachis hypogaea)

A field experiment was carried out on the neutral soil of Student’s Instructional Farm, Barajaguli, B. C. K. V., Nadia, West Bengal with groundnut during pre-kharif season (Feb-June) of 2001, 2002 and 2003. It revealed that in increasing plant height (cm), no. of branches per plant, leaf area index (LAI), dry matter accumulation (gm per m2) and no. and dry weight (gm) of nodules per plant at different dates of observation, Rhizobiumwas more effective than phosphobacterium. Again it was found that Rhizobium was more effective than phosphobacterium for higher pod yield, shelling percent, oil and protein content. Regarding nutrient concentration Rhizobium had better performance in N and K concentration but phosphobacterium gave better result in P concentration though the uptake of all the three nutrients was higher in Rhizobiuminoculation. Cobalt @ 0.21 kg per ha gave best result in all the above-mentioned parameters.