Detection Of Seed-Borne Fungi And Resistance Comparison To Downey Middew,Rust Of Diverse Alfalfa Varieties

In resistance to alfalfa downy mildew among the varieties, But they were susceptible to alfalfa rust.Chen dong, Zhong mu3,Xin mu1 have a certain resistance toalfalfa rust,but they were susceptible to alfalfa downy mildew. With the gradual expansion of alfalfa acreage, Alfalfa diseases occur more serious. Infected seed can provide the conditions for longdistance spread of germs in the field. Sowing the infected seeds has become the primary infection source of disease. In this study,with detecting species from home and abroad 11 alfalfa varieties of fungi, and determine its pathogenicity, and in the field comparison test varieties to downy mildew and rust resistance.The main findings are as follows:13 genera and 16 species of fungi were detected in eleven alfalfa seeds from the United States, Canada, Australia, China, Xinjiang, Heilongjiang, Ningxia, Gansu the different regions at home and abroad. The carrier rate of without the seed surface disinfection was13.5%?87.5%,the average carrier rate was 36.9% and the carrier rate of the seed surface disinfection was3.5%?46.5%,the average carrier rate was 19.6%,There is a big difference between the seed infection rates of the same origin and diffirent origin, The seed infection rate of the United States, Canada, Australia are higher than domestic alfalfa seed infectnon rate.The carrier rate of Aergangjin is higher than Xinjiangdaye,Longmu806,Xinmu1 hao,Sandeli,Liangmu,Gannong1 hao for 55.5%,61.5%,64.5%,70.5%,72.5%,74%.After Inoculations, 15 kinds of fungi can significantly reduce the the germination rate and germination potential, delay germination rate, inhibit the growth of seedlings, reduce the biomass of seedlings,They are Aspergillus niger, A.flavus, A.sydowii, A.versicolor, Penicillium italicum, Bipolaris sorokiniana, Chaetomium elatum, Rhizopus stolonifera, Stachybotrys atra, Cladosporium sp, Gliomastix murorum, Atemphylium botryosum, Verticillium dahlia,Alternaria alternata, Fusarium sp.But Paecilomyces persicinus can promote the seed germination and significantly improve the germination rate and germination vigor index.Shun lu,3010,Ju neng 2,Jing xi,San de li,Ju neng 7,A di na,Liang mu,4020,Ju neng 6,WL343 HQ,Gan nong 4,Xian xing zhe 13 varieties have better resistance to alfalfa downy middew and rust,Xin jiang da ye,Huang hou,Xin mu2,Cao yuan2 were susceptible varieties and not suitable for large-scale cultivation in the local.Kang sai,Tai yang shen,4010,Chao yin su,Jin huang hou,Gan nong 6,A er gang jin,4030,Gan nong 3,WL319 HQ have a certain resistance to alfalfa downy mildew among the varieties, But they were susceptible to alfalfa rust.