Effect of Proteus vulgaris B70 on palisade mesophyll development and root hair growth of French bean

摘要

Plant growth-promoting-rhizobacterium Proteus vulgaris B70, was investigated for its effect on growth pattern, spatial root distribution, leaf palisade dimension in French bean (Phaseolus vulgaris L.). The strain B70 significantly enhanced the growth of the plants in the field. Specific leaf weight (SLAV), net assimilation rate (NAR) and relative growth rate (RGR) were increased by 37%, 74% and 230%, respectively compared to control. Inoculated plants had a greater proportion of root hairs in the zone > 2.5 cm compared to the control. B70 also induced a 93% increase in palisade layer thickness resulting in 26% increase in leaf thickness compared to control. Root colonization studies showed that the strain made up 20%-23% of the total aerobic bacteria. The plant growth-promoting B70 produced siderophores that involved in plant-growth-promotion. From this investigation, conclusion can be drawn that the tested strain could be successfully exploited for sustainable agricultural production without upsetting the environment.