بررسي اثرات تلقيح توأم بذر ارقام لوبيا قرمز با باكتري هاي ريزوبيوم و افزايش دهنده رشد (PGPT) بر عملكرد و اجزاي آن

Evaluation of red bean (Phaseolus vulgaris) seeds co-inoculation with Rhizobium phaseoli and plant growth promoting Rhizobacteria (PGPR) on grain yield and its components

To evaluate seeds inoculation effects on Iranian bean {Phaseolus vulgaris L.) cultivars with different strains of Rhizobium leguminosarum biovar phaseoli with Plant growth promoting bacteria (PGPR) on yield, N2 fixation rate and determining the best bacteria* cultivar combination, a spilt plot experiment in randomized complete block design was conducted in the training farms in Islamic Azad University Shahrekord, Iran in 2006 and 2007. The factor A was six bacterial strains Rb-133, Rb-133 + Azospirillum, Rb-133 + Pseudomonas, Rb-136, Rb-136 + Azospirillum, Rb-136 + Pseudomonas and non-inoculated controls including with and without application of nitrogen fertilizer treatment (100 kgN ha"1). Three bean cultivars Sayad, Akhtar and Goli were assigned as factor B to subplots. The results revealed that there were significant differences among factor A in grain yield, number of pods per plants, number of seeds per pods, number and weight of nods at early flowering (45-50 days after emergence), shoot nitrogen content and N2 fixation rate. Treatment of inoculated seeds with strain bacteria x Pseudomonas and non-inoculated control (without N-fertilizer application) demonstrated the highest and lowest grain yield, respectively. The interaction between strains x cultivars effects in seed yield were not of significant difference, but the results of mean comparison by DMRT (at 5% level) showed the highest and lowest seed yield associated to Akhtar + Rb-133 + Pseudomonas and Goli + control respectively. The results showed that all treatments of bacteria were capable of nodulation; however, strains Rb-133 gave highest nodule dry weight, N total (shoot) and percent of fixed N2. An efficient symbiosis was achieved with strain Rb-133, since total N content of plants inoculated with these strains and N content in soil after harvesting in main plots were similar to that of plants supplied with N -fertilizer treatment.