Dual effect of cytokinene on root-nodule bacteria and their host legumes, in relation to their symbiosis

The stimulatory effect of cytokinene was also reflected on the growth parameters of the legume plants, measured by the length of roots and stems and dry weight of shoots. This effect was most intensive at the combined treatment of with specific rhizobia. The bioassay test using barley as test plant, also revealed that cytokinene extracted from liquid culture media, of different species of rhizobia, had a positive effect on the retension of chlorophyll by the first leaves of test plant. Rhizobium, leguminosarum was the most effective strain in this respect

use of biofertilizers and conditioners in citrus nurseries in relation to microflora contributing to soil fertility

The effect of polyacrylamide gel soil conditioner, phosphate biofertilizer and rock-phosphate application on the microflora of a virgin sandy soil, was studied under sour orange at nursery stage in a pot experiment. There was a noticeable increase in the total bacterial counts in all treatments. Combinations of the three amendments exhibited the highest total bacterial, fungal and phosphate dissolving bacterial counts and extended the stationary phase. The treatments increased the asymbiotic nitrogen fixers, especially the aerobic Azotobacter, more than the anaerobic N fixing clostridia. The counts of nitrifying bacteria also increased more than the control

Field assessment of plant density effect on biological nitrogen fixation by faba beans [vicia faba]

Field experiments were conducted to study the effects of increasing plant density on symbiotic nitrogen fixation by the faba bean /Rhizobium leguminosarum system. Increasing plant density increased the dry matter content of plants. The well nodulated plants had a greater N-uptake, than those plants fertilized with nitrogen. Plant densities up to 160,000 plants/feddan increased pod and seed yields. The results also showed that biological N2-fixation by faba beans was sufficient to supply all the N needed for the plants. However, the limiting factor for yield response, with increasing plant density, is likely to be due to a reduced photosynthetic capacity of the plant population within the limited area