Screening High Symbiotic Matching Combinations Of Rhizobia And Different Alfalfa Varieties

Alfalfa is one kind of perennial leguminous forage with high value of cultivation and utilization in the world. It is also known as the most important green feed because of its salient features including high quality forage, better palatability and high nutritional value, so alfalfa is widely cultivated in our country. One of the most effective methods of increasing the alfalfa yield is vaccination of the matching nodule bacteria on it. In this study, 15 symbiotic strains of alfalfa rhizobia from Daan, Jilin, Nongan, Jilin and Heilongjiang and 3 alfalfa varieties were investigated preliminarily. The growth effect of growth indicators and nitrogen fixation function were analyzed in the pot experiment, 9 alfalfa rhizobia strains were screened out. Therefore, a total of 27 combinations(3 alfalfa varieties × 9 alfalfa rhizobia strains) were made. Then 5 groups high symbiotic matching combinations of rhizobia and different alfalfa varieties were screened out through field trial. The results may provide some theoretical basis for the actual application of rhizobiaand in the agricultural production.The results are shown as following:1. Soil pot experiment simulated soil environment of the field trial, the soil is not applied sterilization in the test of the vaccination of matching the 15 nodule bacteria on the 3 alfalfa varieties. The nodulation rate, nodule numbers, height of plant, fresh weight of plant, dry weight and total nitrogen content of the plant were analyzed. The results suggested that the good nodule bacteria are NACC1001, NACC1004, NACC1005, DACC2001, DACC2003, HLCC3001, HLCC3002, HLCC3003 and HLCC3005.2. Then the 9 nodule bacteria screened out from the soil pot experiment were matched with the 3 alfalfa varieties. The nodulation rate, nodule numbers, height of plant, fresh weight of plant, dry weight and total nitrogen content of the plant were analyzed. Five high symbiotic matching combinations of alfalfa rhizobia and alfalfa varietie were screened out as Gongnong1- NACC1004, Gongnong1- HLCC3002, Gongnong2- HLCC3002, Gongnong5- HLCC3002 and Gongnong5- DACC2001. Our data suggested that HLCC3002 is a widely fine nodule bacteria which can be further applied to practical production.