الفهرس | Only 14 pages are availabe for public view |
Abstract Salt affected soils occupy vast areas especially in the northern part of the Nile Delta. In addition, spots of deteriorated soils are now scattered along the Nile valley. The present investigation was designed to study the effect of certain salts on root nodule bacteria and growth of certain leguminous plants namely berseem and soybean. The beneficial effects of inoculation with Rhizobia need no emphasize. Fourty eight isolates of Rhizobium trifolii and 73 isolates of Rhizobium Japonicum were isolated from berseem and soybean plants grown on different saline soils in Egypt. Only 7 and 11 strains of R. trifolii and R. japonicum respectively were chosen for the present study. The experiments and results obtained could be summarized as follows : A- Effect of Na+ on the growth of rhizobial isolates : The yeast extract mannitol agar (Allen, 1959) was used to test the ability of rhizobial strains to grow on different concentrations of Na+ Great variation was recorded between the different strains. Rhizobium trifolii isolates were found to be more tolerant to the high concentrations of NaCl than that of Rhizobium japonicum. Two and 3 isolates of R. trifolii tolerated 2% and 1% Na+ respectively. |