Soybean Cultivar Mixtures for Managing Soybean Cyst Nematode

The soybean cyst nematode(SCN) resistant variety Kangxian 4 and local soybean variety Heinong 35 were used for planting alone,mixed planting and interval planting in soybean soybean-maize and continuous cropping(15 a) system in Northeast China.This experiment was to examine the effect of using crop genetic diversity to control soybean cyst nematode.The results showed that the soil juvenile 2,cyst on soybean root and SCN eggs at harvesting stage were significantly decreased when the ratio of Kangxian 4 to Heinong 35 was 1:1,and were all lower than those in Heinong 35 planting field alone,while the result was similar to that of Kangxian 4 planting alone.The control was the most effective in soybean mixed planting and interval planting fields.The soybean yield was the highest in soybean-maize rotation and continuous cropping(15 a) system when the ratio of Kangxian 4 to Heinong 35 was 1:1,and it was higher than that in Heinong 35 planting field alone by 8.2%~8.8%,and was higher than that in ratio 4 alone planting field by 2.8%~7.4%.Mixed planting of SCN-resistant variety and SCN-nonresistant variety can effectively control soybean cyst nematode and improve soybean yield.