Screening Of Soybean Resistant To Soybean Aphid And Primary Identification Of Soybean Aphid

Soybean (Glycine max) is one of the most important sources of oiland protein. Oil made from soybean is highly quality and nutritional.Soybean seed is rich in plant protein and is regarded as complete protein,which can provide essential amino acid for humans and livestock. Thus,soybean is known as an alternative of animal protein.Soybean aphid is one of the most severe pests to soybean, reducingthe yield and quality of soybean. In China, soybean productivity could bedecreased by20-30%generally, and by50%with severe aphid outbreak,with enormous economic loss. Recently, as the global warming, soybeanaphis are spreading to more regions. Native to Asia, this invasive specieswas first discovered in North America in July2000and has rapidly spreadthroughout the north central United States, much of southeastern Canada,and the northeastern United States.Therefore, the prevention and cures of soybean aphid have become acritical step during the cultivation of soybean. And screening host plantsresistant to soybean aphid has become the most promising and effectiveway. As the discovery of aphid biotypes, using resistant soybeans toidentify soybean aphid biotypes, and screening high resistant plants have been put priority in the soybean breeding research. The experiment aimedat screening soybean materials resistant to soybean aphid and exploringthe aphid biotypes in some areas of China.From July to October in2010,2011and2012respectively,nonselective test and selective test are designed to screen soybean linesresistant to soybean aphid and to identify aphid biotypes in thegreenhouse of School of Agriculture and Biology, Shanghai Jiao TongUniversity.In2010,14materials were screened to be promising ones resistant toaphid from127resources through selective test based on the aphidnumbers per plant14d and21d after inoculation Shanghai Aphid isolate,including Jiangxi8, Jiangxi9, Jiangxi10, Jiangxi16, Jiangxi22, Jiangxi33,Jiangxi34, Jiangxi35, Jiangxi37, Jiangxi46, Jiangxi2, Jiangxi69,Jiangxi72, Jiangxi75. This experiment laid the foundation for furtherresearches of conforming their resistance and the discovery of aphidbiotypes.In2011, Williams82, PI200538, PI230977, PI567301B, PI567543C,PI243540, PI71506, Dwight, Jiangxi33, Jiangxi22, Jiangxi16, Jiangxi9,Jiangxi8, Dongnong47, Jackson were inoculated with Shanghai aphidisolate, Harbin aphid isolate and Jinan aphid isolate in unselective tests.The results indicated that Dongnong47was susceptible to the three aphidisolates, Williams82and Dwight were also susceptible to the three aphid isolates. PI200538and PI243540were resistant to Shanghai aphid isolate,but susceptible to Harbin isolate. PI230977, PI567301B and PI567543Cwere resistant to Shanghai and Harbin isolates, while PI71506wassusceptible to Shanghai and Harbin isolates. Jiangxi8was susceptible toShanghai and Harbin isolates, while Jiangxi9was resistant to the twoaphid isolates. Jiangxi16and Jiangxi33were susceptible to Shanghaiisolate, but resistant to Harbin isolate. Jiangxi22was resistant to Shanghaiisolate, but susceptible to Harbin isolate. In addition, PI200538wassusceptible to Jinan aphid isolate. However, PI230977, PI567301B,PI567543C, PI243540and PI71506were slightly damaged by Jinan aphidisolate. Therefore, Shanghai, Harbin and Jinan aphid isolates wereregarded as three different soybean aphid biotypes.In2012, Jiangxi33, Jiangxi22, Jiangxi16, Jiangxi8, Jiangxi69,Jiangxi9, Jiangxi37, P746, Dongnong47and Jackson were inoculatedShanghai, Harbin and Guizhou aphid isolates in three differentunselective tests, and were inoculated Shanghai and Harbin aphid isolatesin two selective tests. Results showed that P746and Jiangxi9wereresistant to Shanghai, Harbin and Guizhou aphid isolates. andDongnong47, Jiangxi8and Jiangxi16were susceptible to the three aphidisolates. In addition, Jiangxi22was resistant to Shanghai and Guizhouisolates, but susceptible to Harbin isolate; while Jiangxi33, Jiangxi69,Jiangxi37and Jackson were susceptible to Shanghai and Guizhou isolates, but resistant to Harbin isolate. Therefore, Guizhou aphid isolate wasdifferent from Harbin aphid isolate, but was same as Shanghai aphidisolate.