2016-10-24 03:39:06
Root nodulating soil bacteria called rhizobia are being used as bio-fertilizer to increase the quality and quantity of crops. Soybean is a highly used oil-producing crop. It also a leguminous has a good symbiosis with gram-negative soil bacteria. Bradyrhizobium japonicum and Rhizobium Japonicum are well-characterized rhizobia which interact with soybean root nodules.
Bradyrhizobium japonicum is a slow growing species takes 6-8 hours doubling time and Rhizobium japonicum is a fast grower takes 2-3 hours to become double. These bacteria create nodules on the root of the leguminous plant and convert free atmospheric nitrogen to nitrogenous salt or complex through nitrogen fixation. Nitrogen is an important element for plants’ growth and health.
Root nodulating species of rhizobia has a wild number of varieties and every variety does not function similarly even some of them do not form a nodule. As a result, it is very necessary to identify better one to produce bio-fertilizer at large scale. Bio-fertilizer reduces cost and increases the yield of soybean which will ensure our food security and sufficiency.
In Bangladesh, it is found that slow-growing strains are moderate sensitive to salt, pH, temperature and antibiotics and produce a high number of nodules but the majority of fast growers do not form nodule significantly but can tolerate high salt and antibiotic concentrations. However, every criterion can be used in different purposes; for example, pH tolerant strains can be used as bio-fertilizer at the either acidic or basic area. Moreover, High salt tolerant strains can be used at the coastal area to raise the yield of crops; temperature tolerant strains can be used at the sub-tropical area and intrinsic antibiotics tolerant strains can be used at stressful are
