Symbiotic Properties Of Rhizobia I solates Obtained From Birnin Gwari And Shika In Kaduna State, Northern Guinea Savanna Zone Of Nigeria

A pot experiment was set up in the screenhouse of School of Agriculture and Agricultural Technology, Minna. The experiment consists of 2 factors namely nitrogen sources and soybean varieties. The nitrogen sources are 0 Kg N ha-1, 100 kg N ha-1, USDA110 and rhizobia isolates obtained from soils of Birnin gwari and Shika in Kaduna State (Bg 1-2, Bg 4-2, Bg 5 and Sk 6-3). These treatments were replicated three times and arranged in a Completely Randomized Design (CRD). Prior to the commencement of the experiment, coarse sand was obtained from the river sand, washed thoroughly to remove sediments, dirts and dissolved salts and then autoclaved at 1210C and pressure of -15 bar to destroy microbes. Thereafter, poly pots were filled with 2 Kg of the autoclaved sand and watered with sandsman nutrient solution to field capacity before planting of four seeds of soybeans per poly pot. At 5 days after planting, seedlings were thinned to two, followed by the application of the treatments. At 5 weeks after planting, plants were harvested and nodules were counted before oven-drying alongside shoots and roots to constant weight at 650C for three days. Dry weights of shoots of inoculated plants and that of 100 Kg N ha-1 plants were used for calculation of % Symbiotic Effectiveness = (Shoot Biomass of inoculant/ Shoot Biomass of +N) × 100. Data obtained were subjected to Analysis of Variance (ANOVA) and means were separated using Least Significance Difference (LSD). Results revealed that the highest shoot biomass and percentage symbiotic effectiveness were recorded when TSB 4810 was inoculated with Bg 4-2 while the highest nodulation characteristics were recorded when TGx 1998- 2E was inoculated with USDA110. The heaviest root biomass was observed with TGx 1998-2E plants inoculated with Bg5.