Greenhouse pot experiments were done on biofertilizers P ( B. megaterium ) : Experiment 1(Exp 1) and K (B. circulans ) : Experiment 2 (Exp 2). Rock sources for P (RP) and K and (RK) were rock phosphate and feldspars .The design was a randomized complete block ,factorial. Addition of biofertilizer (B1) and no addition of it (B0) were tested with the rock source (A1) or without it (A0) with 4 treatment combinations of : neither (B0A0), bio only (B1A0) , rock only(B0A1) and both combined (B1A1). Rock phosphate “RP” (150 g P kg-1) and feldspar “RK” (152 g K kg-1) were used at rates of 300 mg P kg-1 , and 240 mg K kg-1 to soil during preparation. Increases in yield of whole plant (shoots+roots) growth (47 days) were 14.0% (B1A0) , 28.7% (B0A1) and 31.1% ((B1A1) in Exp1 and 45.9, 63.6 and 75.1% respectively for Exp2. Respective increases in uptake were 28.9, 42.3 and 71.2% for N , 113 , 131 and 162% for P , and 9.3 , 17.8 and 29.3% for K in Exp 1; 12.7, 10.4 and 47.5 % for N , 42.6, 36.9 and 57.8 % for P and 35.5, 40.2 and 85.0% for K in Exp2. Most positively affected yield as well as P was in the P experiment most affected for K uptake was in the K experiment .Available nutrients after end of growth increased by 75.0 and 50.0 and 77.4% respectively for N ; 26.2% , 1.3 and 56.4 % for P , but no increase for K in Exp1. As for Exp2 no increase occurred to N , and only both sources combined gave an increase (14.5%) ; increases for K were 4.6 , 42.4 and 48.1 % respectively.
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