Rhizosphere microbial diversity analysis of tobacco using carbon source utilization pattern

Biolog Eco plates (Biolog, Inc., Hayward, CA, USA) were used to determine the carbon source utilization pattern in rhizosphere (soil) samples collected from plants of aforesaid four treatments as described earlier [39]. Data were recorded for 7 days at 590 nm and the result obtained at 3rd day was used for statistical analysis. Microbial activity in each microplate expressed as average well color development (AWCD). Diversity and evenness indices, principal component analysis were performed as described earlier. Statistical analyses were performed using SPSS 16.0 and Statistica 7.0.