Fig 4. Population of culturable bacteria (cfu.g^-1 of soil) on LB medium in rhizosheath of wheat.

Wheat-rice rotation (A) and wheat-cotton rotation (B). Plants were inoculated with Azospirillum sp. WS-1, Bacillus sp. T-34 or non-inoculated (control). Bacterial population sizes were measured in rhizosheath soil samples by plating of serial dilutions on LB agar. Log values were calculated for colony forming units (cfu). Given values are the mean of 3 replications. Four different predominant types of colonies (A, B, C, D) could be distinguished as based on 16S rRNA gene sequence analysis.