水稻白叶枯病菌抗药性现象的室内研究

水稻白叶枯病是水稻的主要病害,目前我国防治该病的药剂主要是噻枯唑(川化—018),在含药含菌培养基上,筛选出了叶枯净(5—氧酚嗪)抗性菌,其突变率为2×10~(-6),抗性指数为333。未发现噻枯唑和渝—7802抗性菌。而在活体上直接喷药筛选时既发现了叶枯净抗性菌(抗性指数大于108),又发现了噻枯唑抗性菌(抗性指数大于196),仍然未发现渝—7802抗性菌,进一步的试验证明,噻枯唑活体抗性菌,离体测定时无抗药性,说明噻枯唑活体抗性和离体抗性不一致,而叶枯净的活体抗性和离体抗性一致。交互抗性测定证明,噻枯唑、叶枯净、渝—7802三者之间无交互抗性现象,而噻枯唑与敌枯双之间存在着强烈的正交互抗性。

A RESEARCH ON THE RESISTANCES OF XANTHOMONAS ORYZAE PV.ORYZAE TO BACTERICIDES UNDER LABORATORY CONDITIONS

Rice bacterial leaf blight is a main disease of rice.Now in China the bacteri-cide used to control this disease is saikuzuo (chuanhua-018).The purpose of this research was to study chemical resistance of the bacteria to saikuzuo,etc.the phenazine-resistant bacteria (P^r) were screened out in vitro.Their mutant rate was 2×10^-6,and resistant factor 333.No saikuzuo-resistant basteria (Sa^r) or Yu-7802-resistant ones (Yr) were screened out in vitro.In vivo Pr were easily found,too,with resistant factor more than 108.Sar were also easily found with resistant factor higher than 196 in vivo.No Yr were found either.Further research showed that Sar in vivo were sensitive to saikuzuo in vitro.But Pr in vivo also resisted phenazine in vitro.Cross resistance tests demonstrated that there were no cross resistances among saikuzuo,phenazine,and Yu-7802.