ĐÁNH GIÁ HIỆU LỰC CỦA CHẾ PHẨM VI SINH CỐ ĐỊNH ĐẠM ĐỐI VỚI CÂY ĐẬU TƯƠNG TẠI SƠN LA

Soybean is one of the main legume crops in Vietnam with continuous increase in area and production in the past 5 years. However yields are still low in comparison to other Asian countries with similar soil and climatic conditions. Therefore, a very large unexploited potential for production exists. The experiments conducted in Son La province to determine the effect of rhizobial inoculant on growth and yields of soybean showed that rhizobial inoculant increased number of nodule, plant height and grain yield of soybean. Grain yield was higher than control from 20,07% to 52,47% in Co Noi - Mai Son; 12,89% to 70,03% in Chieng Ban - Mai Son and from 27,16% to 69,13 in Muong Chum - Muong La. Rhizobial inoculant containing CB1809 have given to highest in grain yields. Using rhizobial inoculant can replace N- fertilizer with dose 30 Kg ha-1 and gave to high yield. Indeed, cash income increased from 1.158.000 VNĐ/ha to 2.934.000 VNĐ/ha.