اثر باکتری‌های جنس سودوموناس بر خواص شیمیایی- زیستی خاک، عملکرد و اجزای عملکرد دو رقم برنج

To evaluate the effect of plant growth promoting bacteria (PGPB) on soil physical and chemical indices, yield and its components of two rice cultivars, an experiment was arranged in Rice Researches Institute of Guilan Province during 2009. The experiment design consisted of four randomized complete blocks in a factorial arrangement having 16 treatments in every block. In this research, two factors were evaluated: first, two cultivars (Khazar and Hashemi) and second, eight levels of seed inoculation with PGPB (P.fluorescens strain 168, P.fluorescens strain 93, P.fluorescens strain 177, P.fluorescens strain 136, P.fluorescens strain 103, P.fluorescens strain 169, P.fluorescens strain 4 and control (without inoculation)). Investigated characteristics consisted of: soil minerals, no.microorganisms in soil, grain yield, number of seed per panicle, number of seed per plant, 1000-seed weight, biological and economic yield. In this experiment, effect of cultivar and bacteria were significant in the most of studied characteristics, but effect of cultivar*bacteria (except yield components) wasn’t significant. The results of experiment showed that inoculation with bacterial strains had a stimulating effect on growth and development of rice cultivars. In this experiment, Khazar had positive effect on the most of studied characteristics in compared with Hashemi. Between bacterial different strains, seed inoculation with 168, 177 and 93 strains in compared with other strains increased evaluated characteristics significantly. Seed inoculation with PGPB improved studied characteristics and microorganisms in soil, too.