Pili synthesized by the type III secretion system of Rhizobium species strain NGR234 are essential for protein secretion and thus for efficient symbiosis with many legumes. Isolation and partial purification of these pili showed that they are composed of at least three proteins, NopA, NopB, and NopX. Using biochemical assays, we show here that these proteins interact directly with one another.

We used six rhizobium-legume systems to test the reliability of the most-probable-number (MPN) technique for enumerating rhizobia introduced into 14 sites representing four soil orders. The range-of-transition values (the number of dilution steps between the first not-entirely-positive and the last not-entirely-negative growth units) were compared for each species and for each soil. The probabi...

Family Rhizobiaceae includes fast growing bacteria currently arranged into three genera, Rhizobium, Ensifer and Shinella, that contain pathogenic, symbiotic and saprophytic species. The identification of these species is not possible on the basis of physiological or biochemical traits and should be based on sequencing of several genes. Therefore alternative methods are necessary for rapid and r...

In a field experiment conducted during Rabi 2002-03 at Pantnagar, seed inoculation with Rhizobium leguminosarum bv. viceae (LB-4), PSB (Bacillus megaterium) and PGPR LK-786 (Kurthia sp.) alone significantly increased the nodule number at different intervals, nodule dry weight at 45 and 90 DAS, plant dry weight at 70 and 90 DAS and N uptake by grain and straw in lentil over the uninoculated cont...

Molybdenum (Mo) is required by the enzymes involved in many metabolic processes related to plant growth and development. However, effects of Mo addition on beneficial microorganisms mixed grasslands are unclear. We conducted a greenhouse experiment examine different levels (10 20 mg kg−1 soil form Na2MoO4) perennial ryegrass–white clover two low-Mo soils, as well their symbiotic microorganisms....

Fifty-seven strains of various Rhizobium species were analyzed by two-dimensional gel electrophoresis. Since the protein pattern on such gels is a reflection of the genetic background of the tested strains, similarities in pattern allowed us to estimate the relatedness between these strains. All group II rhizobia (slow growing) were closely related and were very distinct from group I rhizobia (...