AMELIORATION OF SALT STRESS IN SOYBEAN BY Rhizobium BIOFERTILIZER

Abstract

A pot experiment was conducted at Sher-e-Bangla Agricultural University, Dhaka during the period of September to November- 2020 to ameliorate the salt stress in soybean by application microbial biofertilizer. The two factor experiment was conducted by following CRD design with four replications. Factor A consisted of three levels of NaCl viz; S 0 = 0 ppm NaCl pot -1 (Control), S 1 = 1800 ppm NaCl pot

and S 2 = 3600 ppm NaCl pot -1 and Factor B consisted of four levels of biofertilizer viz; B 0 = 0 g Rhizobium @ 50 kg seed, B 1 = BARI RGm-907 @ 25 g/50 kg seed, B = BARI RGm-922 @ 50 g/50 kg seed and B = BARI RGm-928 @ 75 g/50 kg seed. Result revealed that salinity decreases plant height, leaf number, SPAD value, RWC, pod plant -1 3 , seed yield and other yield attributes. Exposure of 1800 ppm and 3600 ppm NaCl decreased seed yield by 48.34% and 56.83% in soybean compared to control by decreasing pod number. Application of different biofertilizers significantly influences growth and yield of soybean. BARI RGm-922 (50 g/50 kg seed) application recorded the highest number of pods plant -1 , seeds pod (3.11), 1000 seeds weight (88.61 g), seed yield (6.54 g pot -1 -1 ), stover yield (19.75 g pot ), biological yield (35.56 g pot -1 ) and harvest index (24.69 %). Different types of biofertilizer application under salt stress condition recovered growth and yield loss of soybean. Among the biofertilizers BARI RGm-922 (50 g/50 kg seed) gave highest seed yield in all stresses viz S 0 B 2 (9.77 g pot -1 ), S 1 B 2 (5.14 g pot -1 ) and S (4.70 g pot -1 ) comparable to others treatment combinations. So, it might be concluded that, the growth and yield of soybean decreased with the increasing dose of salt and application of different biofertilizers recovered growth and yield of soybean by ameliorating salt stress. However, application of BARI RGm-922 (@ 50 g/50 kg seed) as biofertiizer might be the best approach to reduce the salt induced damages in soybean.