Received: 03-11-2014 / Accepted: 04-06-2015
A pot experiment was conducted in greenhouse conditions at Viet NamNational University of Agriculture to determine the effects of waterloggingon agronomical and physiological traits related to nitrogen fixation ability of nodule bacteria (Rhizobium) in soybean at the flowering stage. Seeds of each cultivarwere sown in pots containing 6 kg dry soi. When plantstartedflowering, each pot was subjected to flood and maintained 3cm-water for one week at flowering stage. The results showed that the number of nodules and mass of nodules, leaf area, total chlorophyll content, carbon exchange rate, dry matter accumulation, total protein content and individual plant yieldwere significantly reduced underflooding conditions. D140 and D912 varieties showed better growth, recovery and final yield under flooding conditions (4.85 and 4.67 g/plant) while AK03 variety was the most affected by flooding stress(3.55 g/plant).
