Identification Of Species And Pathotypes From Four Cereal Cyst Nematode Populations In Huanghui Wheat Plant Area And Evaluation Of Main Wheat Cultivars Resistance To Two Populations

The Cereal Cyst Nematode (CCN) has become an important disease in the wheat production and cause serious economic losses at present in China. This article studied the species and pathotypes of four CCN populations in Huanghui wheat plant area and the resistance of 47 domestic cultivars to Xingyang and Xuchang populations in the greenroom and in the field. The main research contents and results as follows:The morphological characteristics of cysts and larvae are observed and measured by 1ight microscope. The results showed that the pououlation in Xuchang has distinct udbridge which was different from the populations in Xingyang,Angyang and Baoding. According to the main morphological measurements of cysts and the second juvenile.The pououlation in xuchang was identified as Heterodera filipjevi, and the other populations were Heterodera avenae.The pathotypes of four populations of CCN in Huanghuai wheat plant area were identified by using the International Host Differentials Set (IHDS). The results showed that the three H. avenae poulations were different from each other and also different from the 13 pathotypes that have been described and nominated.The pathotype of Xingyang population is similar to Ha13 which is the dominant pathotype in Australian. The resistance reactions of the population in Xingyang to 13 cutivars of group A of IHDS which has 12 cultivars aggregately is same to the pathotype Ha13. the population in Xingyang and the pathotype Ha13 have 12 similar resistance reactions aggregately to 13 cutivars of group A of IHDS ,except that the IskamishK-2-light is resistant to Xingyang population and susceptible to the Ha13. The pathotype of Baoding is the same as the pathotype of Dingzhou which is reported 1996 by Pengdeliang. There are the same resistance reactions in the 19 common test host.The pathotype of Anyang is similar to the pathotype of Baoding. Only the KVL191 is resistant to Anyang population but susceptible to the Baoding population in group A .there are also two hosts which have different resistance reactions in group B.The pathotype of Xuchang H. filipjevi population is similar to the"Gotland strain West"which is reported in 1985 by Ireholm in Sweden. Except that Psathias was susceptible to Xuchang population and resistant to the"Gotland strain West"obviously in the17 common test host, the other 16 were relatively similar.The disease resistance of 47 cultivars (lines) which are planted in Huanghuai area to H.avenae Xingyang population and H. filipjevi Xuchang population were identified and evaluated in the greenroom and in the field respectively. The results indicated that most of 47 domestic cultivars are susceptible or high susceptible. Few of them are resistant cultivars. According to the relative resistance index (RRI), the results of the Xingyang population in the field indicated that there were no immune cultivars in all cultivars. Only Taikong 6 was the high range of resistant cultivars. Xinmai 18 ,Zhongyu 6 and Xinmai 11 were the range of resistant cultivars; the 20 cultivars(Kaimai 18 ,Wenmai 4, Xinmai 19 and so on ) were the range of moderately susceptible cultivars;the 12 cultivars(Zhoumai 17,Xinmai 9-998,Yumai 58 and so on ) were the range of susceptible cultivars; the 11 cultivars (Wenmai 19,Aikang 58,Fanmai 5 and so on ) were the range of high susceptible cultivars. Investigated the initial population (PI) and final population (PF) of wheat rhizosphere, the result showed that Taikong 6 ,Xinmai 11, Zhongyu 6 and Xinmai 18 were range of resitance cultivars which PF/PI were≤1.The others cultivars were range of susceptible cultivars which PF/PI were>1. The result in greenroom is similar to the result in the field. In all tested cultivars, there were no immune and high resistant cultivars. 4 cultivars (Taikong 6, Zhongyu 6, Xinmai 11, Xinmai 18) were the range of resistant cultivars: the 22 cultivars (Xinmai 19,Zhoumai 20, Zhoumai 17, Xinmai 208, Yunong 201, Wenmai 4, Yumai 49 and so on) were the range of moderately susceptible cultivars; the 14 cultivars( Huaimai 16, Puyou 938, Zhengmai 9023,Xinyuan 958 and so on) were the range of susceptible cultivars; the 8 cultivars( Zhoumai 18, Yumai 18, Wenmai 19, Yumai 58 and so on) were the range of high susceptible cultivars.The identification result of resistance to H.filipjevi Xuchang population in the field showed that there were also no immune cultivars in all cultivars. Only Taikong 6 and Zhongyu 6 were the range of high resistant cultivars. Yanzhan 4110, Pumai 9, Yunong 202 and Yunong 949 were the range of resistant cultivars. The 31 cultivars (Aikang 58, Xinyuan 958, and Zhoumai 17 and so on) were range of moderately susceptible or susceptible cultivars. The 13 cultivars (Wenmai 19, Lankao 906 and so on) were range of high susceptible cultivars. There was also remarkable difference of PF/PI. The 4 cultivars (Taikong 6, Zhongyu 6, Pumai 9 and Puyou 938) can inhibit the proliferation of cysts because of PF/PI≤1. They were the range of resistance cultivars.The others cultivars were range of susceptible cultivars because of PF/PI>1. The results in greenroom are different from the resuls in the field. There were no immune, high resistant and resistant cultivars. Only 4 culativars (Taikong 6, Zhongyu 6, Pumai 9 and Puyou 938) were the range of moderately susceptible cultivars. The others cultivars were the range of susceptible or high susceptible cultivars.