The Races Of Physiological Differentiation For Different Populations And The Developing Of Assistant Differential Hosts For Heterodera Glycines In China

The soybean cyst nematode (SCN, Heteradera glycines Ichinohe) groups virulence diversity as a starting point to analyze the genetic diversity and genetic differentiation of soybean cyst nematode virulence phenotype and geographic populations, from the level of virulence phenotype to analyze soybean cyst nematode populations of different geographic differentiation of pathogenicity. The main research results are as follows:1.SCN population density was detected at 82 soil samples of 15 groups from the fields of soybean production in China from 2013 to 2014, and all the groups were found SCN, the total detection rate of SCN was 69.4%. And among 15 populations were identified races that had 5 races, race 1, race 2, race 3, race 4, race 6 and race 14. The sample collected from Xuzhou city of JiangSu province, Kangping county of Liaoning province and Jinan city of Shandong province is race 1; The sample collected from Qiqihaer of Heilongjiang province is race 2; The sample collected from Suzhou city of Anhui province, Daqing city of Hwilongjiang province, Shenyang city of Liaoning province and Yinchuan city of Ningxia province is race 3; The sample collected from Zhenyuan County of Gansu Province,Shangqiu city of Henan province, Zhengzhou city of Henan province, Fenyang city of Shanxi province and Yan’an city of Shanxi province is race 4; The sample collected from Dalian city of Liaoning province and ChiFeng city of Mongolia is race 14. Wherein the identification results of Suzhou city of Anhui province, Zhenyuan County of Gansu Province, ChiFeng city of Mongolia, Yan’an city of Shanxi province, Ningxia city of Yinchuan province have not been reported previously.2. From 2014 to 2015,37 soybean cultivars were evaluated for the resistance to SCN in the filed of Shenysng,Kangpina and Daqing. The result from the tests of SCN race 1 in the filed of Kangping showed that 33 out of 37 soybean cultivars were high resistance and lwere medium resistance,2 soybean cultivars were medium susceptible and 1 were susceptible and there were 3 soybean cultivars were immune. In teses to SCN race 3 in the field of Shenyang showed that among the 37 cultivars,32 were high resistance,3 were medium resistance,1 were susceptible and only Wuzhai soybean were immune. The result from the tests of SCN race 3 in the filed of Daqing showed that 34 soybean cultivars were high resistance,2 were medium resistance,1 were susceptible and the immune cultivars were Pingdingshan black soybean.3. SCN race 3 continuoused propagation 5 generations with the method of individual gravid females inoculation, the result showed that two single-female lines changed from race 3 to race 1 and 6. Verified SCN populations genetic diversity from the level of virulence phenotype verified.4.8 groups of race 4 were comparaed with females index as evaluation criteria, the result showed that infection ability was significantly different in the 8 groups for the differential host and susceptibility cultivar. The female index of Yan’an group were higher than the other groups, so the group was the strongest infection and higest virulent. The groups from Shangqiu, Zhengzhou and Fenyang were lower than other groups in femals index and infection. The result of resistance identification showed that the cultivars of Huipizhi, Wuzhai, Yingxian black soybean were high resistance, two cultivars of Haerbin and Xiaoli black soybean cultivars had ability to distinguish the 8 groups to 3 categories. The two soybean cultivars could regionalization the groups of race 4 more detailed with the original differential hosts, became the secondary differential hosts.