The effects of application of different doses of molybdenum on the Rhizobium bacteria population in the bean (Vicia faba L.) growing soil

In this study the effect of increasing doses of molybdenum on Rhizobium bacteria whic is effective on the symbiotic nitrogen fixation of bean plant.investigated.Research was conducted in unheated plastic greenhouses located at COMU Agricultural Faculty, Department of Soil, between October 15, 2010 and, April 28, 2010.Eresen 87 bean cultivars were used as an experimental material for the study. The bean seeds were planted in the pots, filled with the equal amount of farm soil and treatmets included; control, 5 doses of molybdenum (0; 0,05; 0,10; 0,15;0,20 ppm that were applied as Amonyummolibdat (NH4) 6Mo7O24.4H2O).In the experiment, the effects of molybdenum doses on the growing bean plants, the number of nodules in plant roots, nodules activity status, wet weight of nodules, nodule dry weight and number of soil bacteria Rhizobium issues were investigated by examining the changes in flowering and harvesting periods.As a result, doses of molybdenum did not significantly effect on number of nodules, nodule activity, nodule age weight, nodule dry weight and Rhizobium bacteria but periods showed statistically significant effect on the plants nodule activity, nodule age weight, nodule dry weight.Besides, it is concluded that the periods have not an important effect on the number of Rhizobium bacteria. (p< 0,01).Key words: Bean, Molybdenum, Rhizobium