Effect of cogenerated bagasse ash on microbial population and enzyme activities in sugarcane grown soil

A field experiment was conducted during 2016-18 on an Inceptisol of Rahuri, Maharashtra to study the effect of cogenerated bagasse ash on microbial population and enzyme activities in preseasonal sugarcane (Sachharum officinarum) var. CoM 0265. The results indicated that the treatments which received 150 % RDK through cogenerated bagasse ash recorded the higher total bacteria (44.11, 45.89 and 32.78 cfu x 106 g-1 soil), fungi (17.78, 18.89 and 15.89 cfu x 105 g-1 soil) and actinomycetes (18.33, 19.22 and 15.78 cfu x 105 g-1 soil) count at earthing up, grand growth and harvest stage of preseasonal sugarcane, respectively. On the other hand, the highest dehydrogenase (13.38, 14.03 and 7.92 µg TPFg-1 soil h-1), urease (49.35, 51.68 and 38.15 µg NH4-N g-1 soil h-1), acid phosphatase (17.92, 18.85 and 13.23 µg PNP g-1 soil h-1) and alkaline phosphatase (64.81, 65.94 and 39.07 µg PNP g-1 soil h-1) enzyme activity in soil were also recorded in T9 (150 % RDK through cogenerated bagasse ash) at earthing up, grand growth and harvest stage of preseasonal sugarcane, respectively. The results of the present study revealed that the microbial population and enzymatic activities of the soil were increased at initial stages and thereafter, progressively decreased with crop growth stages by the application of cogenerated bagasse ash. Application of 150 % RDK through CBA (6.62 t ha-1) along with recommended dose of nitrogen and phosphorous (340 and 170 kg ha-1) through inorganic fertilizers and 20 t ha-1 FYM has improved the microbial population as well as enzymatic activities in sugarcane grown soil.