Enhancement of Maize Growth Using Some Plant Growth Promoting Rhizobacteria (PGPR) Under Laboratory Conditions

Abstract

Abstract: Thirty one bacterial isolates were isolated and identified in nine genera, with twelve taxa as Pseudomonas putida, P. fluorescens, P. areuginosa, Serratia marcences, Xanthomonas sp., Bacillus cereus, Microccoucs sp., B. subtilis, B. megaterium, B. amyloliquefaciencs, Pseudomonas sp., Staphylococcus sp. The highest percentage distribution was B. subtilis, followed by P. putida, P. areuginosa and S. marcences. Eight isolates had the ability for production of IAA and siderophores. S. marcences then P. putida followed by P. fluorescens were the highest in IAA production. The eight isolates of PGPR were increased seed germination by 7 to 13% over control. The highest seed germination was recorded when seeds were pretreated with S. marcences, then P. putida followed by B. subtilis. The highest seedling height and shoot dry weight were observed in seeds treated with S. marcences then P. putida followed by B. cereus and B. subtilis. The use of S. marcences produced the highest root length and weight, and also increased the chlorophyll contents. The MDG was the highest in case of seed soaking and inoculums added with irrigation water treatments, while was the lowest at spry the inoculums on the soil surface. Also, the best results for MGT and GI was found in seed soaking and inoculums added with irrigation water treatments. The best PGPR bacteria for MDG, MGT and GI in seed soaking treatment were B. megaterium, P. putida, S. marcences and P. areuginosa, while in adding inoculums with irrigation water were B. subtilis, B. cereus, S. marcences and P. fluorescens. When cultured the high efficacy isolates of Serratia marcences with Pseudomonas pitida and Bacillus subtilis without any antagonistic effect between them