Soybean cyst nematode Heterodera glycines is one of the most serious soil-borne pathogens in soybean production. However, the researches were limited in China due to lack of an effective pathosystem. In this study, we screened 21 legume Medicago plants in both Medicago truncatula and Medicago sativa to obtain candidate model plants for establishing a new pathosystem for legume-H. glycines interactions. The nematode infection of tested plants was assayed with Race 3 and 4 respectively, which were two dominant H. glycines inbred races in China soybean producing areas. The results showed that the model legume plant M. truncatula A17 failed to allow Race 3 of H. glycines to complete its life cycle, in contrast, it provided the Race 4 population to form several cyst nematodes, however, the female index(FI) value was approximately 1.6. Three M. sativa cultivars, including Xunlu, Aergangjin and Junren, provided either Race 3 or 4 of H. glycines to develop into mature cysts with their FI value below 5 as well. Our results demonstrated that legume plants in both M. truncatula and M. sativa were not likely to be a model plant for H. glycines because of an extreme high resistance.
KONG Ling-anWU Du-qingHUANG Wen-kunPENG HuanHE Wen-tingPENG De-liang
The cereal cyst nematode(CCN, Heteroder aavenae) causes serious yield loss on cereal crops, especially wheat, worldwide. Daxing population in Beijing City and Huangyuan population in Qinghai Province, China, are two CCN populations. In this study, the CCN pathotypes of Daxing and Huangyuan populations were characterized by tests on 23 standard "International Test Assortment" with the local species Wenmai 19 as the susceptible control. Tested materials were grouped by three nematode populations' virulence on resistant genes(Rha1, Rha2, Rha3, Cre1) and nonresistant genes, varieties and lines. Both Daxing and Huangyuan populations were avirulent to Ortolan(Ha1). Barley cvs. Ortolan, Siri, Morocco, Bajo Aragon 1-1, and Martin 403-2 were all resistant to both populations. Cultivars Herta, Harlan 43 and wheat Iskamish-K-2-light were all susceptible to Huangyuan population, all of them, however, were resistant to Daxing population. The other five oats were all resistant to the two tested CCN populations. Except Iskamisch K-2-light, all the other wheat cultivars(Capa, Loros×Koga, AUS 10894, and Psathias) were susceptible to Daxing population. Because the pathotypes of the two tested CCN populations in Beijing and Qinghai were not identical to any of the 13 pathotypes previously characterized by the test assortment, we classified Daxing and Huangyuan populations as the new pathotypes, named Ha91.
CUI Jiang-kuanHUANG Wen-kunPENG HuanLIU Shi-mingWANG Gao-fengKONG Lin-anPENG De-liang
