中文摘要：

通过考察短梗霉素 A（AbA）对灰葡萄孢菌野生株 BcAUR1及其 AUR1基因内含子缺失突变株 BcAUR1a 生长的影响,明确 AbA 抑制真菌生长的机理。AbA 敏感性试验表明,低浓度 AbA （8μg/mL）显著抑制野生株BcAUR1菌体的生长,高浓度 AbA（50μg/mL）存在下观察不到 BcAUR1的生长迹象。突变株 BcAUR1a 则不受AbA 的影响,在低浓度和高浓度 AbA 存在下均能正常生长。AbA 抑制 BcAUR1侵染柑橘果实,但 BcAUR1a 在高浓度 AbA 存在下也能够有效感染柑橘果实。这两个试验均证实了突变株 BcAUR1a 具有 AbA 抗性。电镜观察表明,AbA 引起 BcAUR1细胞质膜和内膜系统形态异常,质膜和液泡膜断裂,细胞内物质泄露。AbA 抑制灰葡萄孢菌生长的机制是由于 IPC 合成酶受到抑制,导致鞘磷脂类物质合成不足,细胞膜结构破坏,胞内物质外漏。

英文摘要：

In order to clarify the mechanism of aureobasidin A（AbA）inhibiting the growth of fungi,the effects of AbA on the growth of B .cinerea wild strain BcAUR1 and strain BcAUR1a with deletion of the intron of AUR 1 gene were investigated.The experiments of AbA sensitivity showed that low concentration of AbA （8 μg/mL）sig-nificantly inhibited the growth of BcAUR1,and there was no sign of BcAUR1 growth under high concentrations of AbA （50 μg/mL）.However,AbA had no impacts on BcAUR1a,which could grow normally at low or high concentrations of AbA.Additionally,AbA could inhibit infection of BcAUR1 to citrus fruits,but BcAUR1a could infect citrus fruits effectively even at the presence of high concentration of AbA.Both results confirmed that BcAUR1a had a resistance to AbA.The observation by electron microscopy showed that AbA caused morphologi-cal abnormality of BcAUR1 cell membrane and inner membrane system,the fracture of plasmalemma and tono-plast,and the leakage of intracellular substances.The mechanisms that AbA inhibited the growth of B .cinerea was that IPC synthetase was inhibited,which caused insufficient synthesis of sphingomyelin substances,damage of cell membrane structure and leakage of intracellular substances.