Combined Effects of Rhizobium and Vesicular Arbuscular Fungi on Green Gram (Vigna radiata L. Wilczek) under Temperate Conditions M I Bhat, S A Bangroo, Tahir Ali, S R S Yadav* and M A Aziz Division of Soil Science, S. K. University of Agricultural Sciences and Technology of Kashmir, Shalimar-191 121, Srinagar, (J & K), India *Central Research Institute for Jute & Allied Fibres, Barrackpore, Kolkata, India e-mail: iqbalbhat786@yahoo.com A B S T R A C T An investigation was carried out to study the effect of Rhizobium (Bradyrhizobium spp. vigna) and vesicular arbuscular mycorrhizal fungi (Glomus fasiculatum and G. mosseae) along with or without nitrogen levels on green gram (Vigna radiata L. wilzeck) var Shalimar moong-1 under temperate conditions. Seed inoculation with Rhizobium significantly increased dry weight of nodules plant -1 , grain and straw yield, nitrogen, phosphorus and potassium uptake over the control. Similar results were observed with soil inoculation of VAM fungi. Maximum dry weight of nodules plant -1 was observed with application of nitrogen @ 15kg ha -1 whereas maximum grain and straw yield were observed with application of nitrogen @ 30kg ha -1 . An increase in yield of grain and straw was 17.8 and 17.1% due to application of 30kg N ha -1 over 15kg N ha -1 . Combined inoculation of Rhizobium and VAM fungi increased further nodulation, grain and straw yield and NPK uptake and maximum were observed with Glomus fasiculatum x Rhozbium interaction. The highest grain (9.45q ha -1 ) and straw yield (23.85q ha -1 ) was recorded with G. fasiculatum x Rhizobium x 30kg N ha -1 interaction but that was at par with G.mosseae x Rhizobium x 15kg N ha -1 interaction. Key words: Green gram, Bradyrhizohium, NPK uptake, VAM fungi and Glomus Legume and Rhizobium symbiosis contributes at least 90 × 10 6 metric tonnes of N per year (Subba Rao 1982). Nitrogen requirements of pulses are much greater than the cereals or oil seed crops, for producing the equal among of grain. Application of Rhizobium has contributed to the increase of about 4 quintals grain ha -1 matching to about 32 kg N ha -1 application through fertilizers in soybean (Subba Roa et al. 1982). It has been established that vesicular arbuscular mycorrhizal fungi improve plant growth through increased uptake of mineral nutrients especially those which are relatively immobile in soil such as phosphorus, zinc and copper. Under low fertility conditions inoculation with VA- mycorrhizae fungi increases nodulation, root- colonization, drymatter accumulation in shoot, nutrient uptake and soil fertility status (Singh and Singh 1993). Tarafdar and Rao (2001) also reported positive interaction between Rhizobium and VAM inoculation on nodulation and nutrient uptake. Therefore, an attempt was made to assess response of different species of VAM fungi and Rhizobium with or without nitrogen levels in respect to nodulation (dry weight of nodules plant -1 ), fertilizer substitution, straw and grain yield and nutrient uptake (NPK –uptake). MATERIALS AND METHODS A field experiment on green gram var SM-1 (Vigna raidata L. Wilczek var SM-1) was conducted in typical alfisols during kharif season of 2005 at experimental farm of SKUAST-K, Shalimar. The soil was silty clay loam in texture, with initial organic carbon 0.81%, alkaline KMno 4 N328.6 kg ha -1 , Olsen’s P 9-6 kg ha -1 , NH 4 O AC K 115.8 kg ha -1 , pH of 6.8, solubridge conductivity (EC dsm -1 ) at 25 o C) of 0.26. The experiment was laid out in a randomized block design with factorial arrangement of eighteen treatments replicated thrice. The treatments consisting of 3 levels each of N (0, 15 and 30 kg ha -1 ), VAM fungi (M 0 (un- inoculated), M 1 (G. fasiculatum) and M 2 (G. mosseae) and two levels of Bradyrhizobium spp. vigna (R 0 ) uninoculated and R 1 (inoculated with Bradyrhizobial spp. vigna). Soil based VAM inocula of both strains containing hyphae, spors, spore carp and infected root fragments were applied to the open furrous @ 15kg ha -1 using field soil to bulk the carrier in a uniform layer at a depth of about 5cm. Bold and health seed of green gram (Vigna radiate var SM-1) were sown immediately and open furrows were covered with small amount of soil. Inoculation of Bradyrhizobium spp. vigna was done through seed @ 500g ha -1 as per package of practice. Nitrogen was applied in the form of urea as per the treatment as basal dose. Phosphorus and potassium was also applied as per package of practice (i e 60kg P 2 O 5 ha -1 and 40kg K 2 O ha -1 ). The grain and straw samples were analysed for nitrogen content by Kjeldahl method, P content by Vanadomolybdo yellow colour method of Koening and Johnson (1942) and K content by flame photometry by Jackson (1973). RESULTS AND DISCUSSION Research Journal of Agricultural Sciences 2011, 2(1): 17-20 17 www.rjas.info