Occurrence And Distribution Of Cereal Cyst Nematode And Screening Of Resistance And Tolerance Wheat Varieties To Cereal Cyst Nematode In Xiaoxian County In Anhui Province

Cereal cyst nematode （CCN） is a important nematode disease on wheat and othercereal crops, seriously impacting on wheat yield，which potential threaten to wheat yieldand food safty. The CCN distribution had been reported [20₂1] in Australia, South Africa,Mexico，Japan and other countries and regions as well as most of the European countries.Including more than40wheat producing countries, such as United States, Russia andChina, totally caused a loss of about$300million per year. Much heavy loss occurredin Europe, Asia and Australia. CCN becomes one of very econimically inportant cerealdisease all over the global[22]. Anhui Province is the third largest wheat-producing area inChina, it’s also the major wheat production base in China, wheat planting area reaching2.36million hectares, accounting for85%of the arable land, the total output reaching11.854million tons, accounting for10.5%of the country’s total wheat output of10.5million tons in2010，accounting for36.7%of the province’s total grain output of28.6million tons. The CCN distribution is clear in Anhui Province,but little is known of CCNspecies, for the purpsoe to extablish a comprehensive measures to control CCN disease inAnhui Province, we idenified CCN species, investiagted CCN distribution rule in theNorthern Anhui province, and carried on ifeld resistance and tolerance screening trials inXiaoxian county.For the purpose of survey CCN species occurred in Wanbai wheat area in AnhuiProvince, soil smaples of”wheat rhizosphere were collected b“y zig-zag method inDangshan County, Xiaoxian County, Chuzhou County and Shouxian County in December2012， CCN cysts were isolated by Fenwick&Oostenbrink meathod, Juvinile2（J2） ofCCN were isolated by Baermann funnel method, morphorlogical idenitifcate of CCNwas carried on under an optical microscope, morphorlogical data was measured by de-Manformula, species was determined based on the morphological characteristics of the cystsvulva cone. The results show: CCN species occurred in Dangshan County, XiaoxianCounty, Chuzhou County and Shouxian County was Heterodera avenaes.A ifeld survey was carried out from2007to2010，in Xiaoxian county of AnhuiProvince aiming to investigate the CCN occurrence and CCN distribution rule of underdifferent altitude, soil type and cultural practice, such as crop rotation. Totally360soilsamples were collected by random survey method, cysts were isolated by lfoat method,calculating both the number of white female and cyst, also nematode occurrence; egg density was determined based on30cysts of each sample site, egg density occurrencequantity （EDQ） frequency was analyzed by Frequency statistic, EDQ values underdifferent altitude, soil type and cultural practice were compared by variance analysis. CCNspecies was identiifed based on the morphological characterizations of female vulva coneand de Man data. The results show that CCN occurred in wheat ifeld in Xiaoxian countywas identified as Heterodera avenae, CCN occurred in87%surveyed sampling fields inXiaoxian county. Wheat ifeld EDQ of higher altitude （31-40m） was signiifcantly higherthan that of lower altitude ifeld （21-30m）（p <0.05）; wheat ifeld EDQ with soybean aspro-crop was signiifcantly higher than that with maize as pre-crop in sandy soil type wheatifeld {p <0.05); EDQ varied in different soil type ifled not signiifcantly. This paperindicated CCN occurrence and distribution follow certain rules in Xiaoxian county for theifrst time, thus provided theory foundation for the relevant government departments tobuilt control measures against CCN in this area.For dedueing CCN hating time in the ifeld in Anhui province, providing forcastingstudy data, a indoor experiments was designed for studying the correlation between storagetime and J2hatch. The results show, hatch number increased by the time in4weeks in4°C，and reached high peak at the end of4th week at the same temperature. Hatching timeand infection time in ifled in certen wheat area was discussed based the optimum hatchtime and tempeature combining with meteorological data.For the purpose of screening wheat varieties for the resistance to Xiaoxian countyCCN, from September2011to May2013，making use of the Xiaoxian ifeld trials, weidentiifcated the resistance of17wheat varieties such as Han3475and the tolerance ofseven wheat varieties patience such as Luomai the8th. Identiifcation results showed that:Handan3475，the new wheat26，Xumai31，Su553，Wanmai53is moderately susceptible,anther11wheat varieties such as Huapei8th，Shannong22is highly susceptible; Luomai8and Yunong035has tolerance, other ifve wheat varieties such Xuzhou954has notolerance.Failed to ifnd immune varieties.