Study of micro-organisms from root regions of rice

Abstract

The qualitative and quantitative features of micro-organisms occurring in association with rice var IR-8 were studied. A comparison between the micro-organisms present in the soil, rhizosphere and rhizoplane regions of fertilized and unfertilized plots was made. A total of 49 species of fungi were isolated and identified during the course of this work. A higher number of fungal and bacterial colonies was present in the soil of root zone than the root-free soil. The highest number of fungal and bacterial colonies was found in the rhizosphere region of the fertilized plots. The work further revealed that more fungal representatives were present in the fertilized plots than the unfertilized plots. The bacterial isolates comprised rod and sphere forms, the former out numbering the latter in number of colonies. Both spore formers and non-spore formers constituted the rod forms. The bacterial colonies were more in number than the fungal colonies. One of the most dominant bacterial colony was studied and identified asBacillus subtilis. There is no report of a detailed study about micro-organisms present in association with rice plants of Bangladesh.