影响水稻纹枯病菌营养体亲和性分化的因子

The im pact factors on differentiation of som atic com patibility of Rhizoctonia solani AG-1-IA

为了探明影响水稻纹枯病菌营养体亲和性分化的因子,将水稻纹枯病菌菌株cx-2在不同水稻品种继代接种,并在含不同杀菌剂、具不同p H及不同温度条件的PDA平板上继代培养,用对峙法测定继代菌株与原始接种菌株的营养体亲和性。此外,对营养体亲和性分化菌株与原始菌株的AFLP指纹图谱进行比较。结果显示,在供试的30个水稻品种上连续接种4次后,从9个水稻品种中分离出与原始菌株营养体不亲和的菌株。菌株在不同p H值的PDA平板继代培养4次后,在p H偏碱性端(p H 10、p H 11)开始出现营养体亲和性分化的菌株。在不同农药和温度条件下继代培养10次的菌株中没有分离到营养体亲和性分化的菌株。营养体亲和性分化菌株与原始菌株的AFLP指纹图谱没有差异。

To clarify the factors influencing differentiation of somatic compatibility in Rhizoctonia solani AG-1-IA causing rice sheath blight,the pathogen strain cx-2 w as consecutively inoculated into different rice varieties and subcultured on PDA plates w ith different fungicides / p Hs or at different temperatures. The comparison of somatic compatibility w as made betw een the recovered / subcultured isolates and their original strain（ cx-2）based on barrage zone formation on the face-to-face cultures. M eanw hile,amplified fragment length polymorphism（ AFLP） w as used to determine genetic difference betw een the recovered / subcultured isolates w ith alterations in somatic compatibility and their original strain（ cx-2）. The results show ed that the isolates w ith alterations in somatic compatibility w ere recovered from 9 out of 30 rice varieties tested after four consecutive inoculations. The subcultured isolates w ith alterations in somatic compatibility w ere also detected after four consecutive transfers on the PDA plates w ith alkaline p H levels 10 and 11. How ever,no subcultured isolates w ith alterations in somatic compatibility w ere found even after ten consecutive transfers on the PDA plates containing different fungicides or at different temperatures. The isolates w ith alterations in somatic compatibility show ed the same AFLP fingerprint patterns w ith their original strain（ cx-2）.