Occurrence And Bio-control Of Cereal Cyst Nematode(Heterodera Avenae)in Inner Mongolia

Cereal Cyst Nematode which damage wheat and barley, oats and other cereal crops is a soil-borne disease, serious impact on wheat production. From1989our country is found for the first time since Cereal cyst nematode, nowadays it has been already throughout China’s10provinces,autonomous regions, causing very large loss, which must have received enough attention. Therefore, in view of Inner Mongolia’s climate and environment, we analyze the occurrence and distribution of the Cereal cyst nematode and preliminary study. After the test, the results show that:From the random investigation of wheat distribution of CCN in Inner Mongolia,we make sure the occurrence distribution of the CCN.2009-2010in the Inner Mongolia wheat and oat, we have wheat soil sampling272,in25county of9region,finding the suburb of the Hohhot,wuchuan,siziwang,liangcheng,huade,chayouzhongqi,ningcheng,keshiketeng,zhalan tun,yakeshi,the infection rate of which reach100%.we have oats soil sampling51sampling,in11county of6region finding hude,taipusi,zhenglanqi, the infection rate of which reach100%,but the number of cysts is Small.On the basis of the random investigation in2009-2010,we have the systematic investigation of wheat distribution of CCN in Inner Mongolia in2011. We have wheat soil sampling95,in14county of6region,finding kalaqinqi,ningcheng,linhe,hangjinqi, the infection rate of which reach100%. We have oats soil sampling50sampling,in6county of3region,finding the infection rate of chayouzhongqi reach83.3%, but the number of cysts is0-5.Cereal cyst nematode biological characteristics and occurrence regularity of to do a preliminary study, investigated the CCN of soil distribution characteristics, temperature on larval hatching,15℃sustained40days incubation and hatching rate of approximately60%in30℃,25℃50%hatching rate, only36%,35℃of nematode eggs fail to hatch. In addition, experiments were conducted in the field and Cereal cyst nematode occurrence were investigated in before Qingming is wheat sowing time, sowing of oats, and in May, July in the middle of the plant roots have started to appear white females,8at the end of volume changes basically no longer.wheat, oats, barley, infection of basically the same, compared with oats and barley, wheat and more susceptible to infection, oat relatively lesser incidence, possible and sowing date later on, wheat seeding after that ushered in the Caenorhabditis elegans hatching peak, sowing late, missed the sporangium germination and hatching the peak, so reducing the infected degree. The paper reviewed research progress on the distribution of CCN in Wheat Rhizosphere.In the0-10cm deep,there is the largest number of cyst, With the deeper soil,the number of cyst decreased.But horizontal distance was no difference.And domestic reported instances of the same, our country cultivates wheat varieties have little resistance, relatively speaking test for oat varieties of incidence light in wheat varieties, We appraisal with12species,the oat varieties Bai Yan8is higher, the average female digital20.2. But the wheat varieties in9high,13in moderately susceptible, and heavy disease. The species is not found in resistant varieties.From the random investigation of wheat distribution of CCN, we have wheat soil sampling50and isolated inselective medium from wheat roots and CCN cyst,which has been happened CCN. by screening to20fungal strains were indoor screening test, obtains two control effect better fungal strains, the disease control effect reaches50%, decay cyst rates were81.4%and72.9%, Preliminary studies on the biocontrol mechanism against wheat cereal cyst nematode,the results showed that Z2and Z4strain had inhibition on egg-hatching,Z2and Z4strains were parasitic on eggs and J2,the fatality rate to eggs and J2were more than50%, Z2and Z4strains were parasitic on eggs and J2,the parasite rate to eggs were respectively10.9%and28.3%.and parasite rate of fungus to juveniles were respectively27.3%and32.8%.Through the observation on morphology and molecular identification, strain Z2was identified as Alternaria cavity Mucorales is an ascomycete, because of this, there are more than80species, all available records and reports and no exactly the same, so this fungus has not been identified to genus, the need for further study on it. In these two bacteria were found in the study of biological characteristics of strains of Z2, either in the pH range or adaptive temperature range is wide, and the bacteria on carbon, nitrogen source and strong adaptability, which is conducive to the late. Z4strains in carbon, nitrogen source adaptability is strong, but the bacteria in alkaline conditions, not suitable for the growth of, and is not suitable for high temperature environment.