Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: 8/3/2006
Publication Date: 11/12/2006
Citation: Hashem, F., Dadson, R., Javaid, I., Green, B., Devine, T.E., Butler, L., Joshi, J. 2006. Response of genetically diverse soybean cultivars to various bradyrhizobium japonicum inoculants [abstract]. American Society of Agronomy Meetings. Interpretive Summary:
Technical Abstract: The economy of the Delmarva Peninsula of the United States is highly dependant on the productivity of soybean. The low cost of soybean production is essential in enhancing the prosperity of farming communities in this region. This can be achieved by minimizing the use of expensive nitrogen fertilizers, and substituting with inexpensive and environmentally friendly rhizobia inoculants. Field studies were conducted in a Randomized Complete Block Design during the last four soybean growing seasons to examine the effect of various Bradyrhizobium japonicum strains and commercial inoculants on nodulation, growth and yield of diverse grain and forage soybean cultivars grown under the Delmarva Peninsula environmental conditions. Surface sterilized soybean seeds were coated with each of the following inoculants before sowing: T11NOD+, NOD+, NOD+ with Extender, NOD+ with Subtilex, Nitragin Cell Tech Sci, Nitragin Optimize, HiStik L N/T containing bradyrhizobia and Bacillus subtilis, Soy inoculant containing strains 532c, NSI and Urbana 212 or uninoculated controls. Soybean nodulation and nitrogenase activity were determined eight weeks after planting while soybean seed and biological yields were determined at maturity. Nodulation, nitrogenase activity and soybean yield varied significantly, and this variation depended on the soybean cultivar tested and the legume inoculant applied. Legume inoculants NOD+ with Subtilix and NOD+ with Extender produced the highest nodule number and seed yield on soybean cv. AG4903. Forage soybean cv. Tyrone was nodulated best and provided a higher seed yield when it was inoculated with TA11NOD+ inoculant.