Abstract: To ascertain the efficacy of various biocides as a means of biological control for diseases affecting Guizhou pepper，the pathogenic fungi Botrytis cinerea and Fusarium graminearum were selected as the research subjects，and the inhibitory efficacy of four biocides on the growth of hyphae，the virulence in an indoor environment，their conductivity，and the leakage of nucleic acids were determined.A propidium iodide solution（PI） staining test was carried out to further investigate the effects of the biocides on the cell membranes of the fungi to ascertain their effectiveness.The results demonstrated that among the four biofungicides，0.5% picrasidine aqueous solution exhibited the most significant inhibitory effect on Botrytis cinerea，with a half‑maximum effect concentration（EC₅₀）of 156.675 1 mg/L.This was followed by 10% polymyxin wettable powder，4% kasugamycin aqueous solution and 28% validamycin soluble powder，with EC₅₀ of 598.681 4，1 485.473 9，2 449.178 1 mg/L，respectively. 0.5% picrasidine aqueous solution exhibited the greatest inhibitory effect on Fusarium graminearum，with an EC₅₀ of 162.536 8 mg/L.This was followed by 10% polymyxin wettable powder，28% validamycin soluble powder，and 4% kasugamycin aqueous solution，with EC₅₀ of 577.307 7，1 833.176 6，1 963.849 1 mg/L.The mycelial conductivity of pathogenic fungi increased following biocide treatment，with the absorbance value at OD₂₆₀ of the treated group exhibiting a significantly higher level than that of the control（untreated with biocide）at 8 h（P<0.05）.The results of the PI test indicated that the biocides had an obvious damaging effect on the cell membrane of pathogenic fungi，exerting their inhibitory effect by destroying the integrity of the cell membrane. In conclusion，the results demonstrate that both 0.5% picrasidine aqueous solution and 10% polymyxin wettable powder inhibit the mycelial growth of both Botrytis cinerea and Fusarium graminearum.The two biofungicides can be employed as biocontrol agents for pepper diseases caused by Botrytis cinerea and Fusarium graminearum.

Key words: Capsicum annuum, Biological fungicide, Pathogenic fungi, Indoor virulence, Guizhou

摘要： 为了获得贵州线椒病害生物防治的有效杀菌剂，以引起贵州线椒果实病害的病原菌灰葡萄孢霉（Botrytis cinerea）和禾谷镰刀菌（Fusarium graminearum）为研究对象，测定4种生物杀菌剂对病原菌菌丝抑制率、室内毒力、电导率以及核酸泄露情况的影响，并开展碘化丙啶溶液（PI）染色试验探究生物杀菌剂对致病菌细胞膜完整性的影响。结果表明，4种生物杀菌剂中，0.5%苦参碱水剂对灰葡萄孢霉的抑制效果最显著，其半数最大效应浓度（EC₅₀）为156.675 1 mg/L，其次为10%多抗霉素可湿性粉剂、4%春雷霉素水剂和28%井冈霉素可溶性粉剂，EC₅₀分别为598.681 4、1 485.473 9、2 449.178 1 mg/L；0.5%苦参碱水剂对禾谷镰刀菌的抑制效果最显著，其EC₅₀为162.536 8 mg/L，其次为10%多抗霉素可湿性粉剂、28%井冈霉素可溶性水剂和4%春雷霉素水剂，EC₅₀分别为577.307 7、1 833.176 6、1 963.849 1 mg/L。致病菌经过生物杀菌剂处理后菌丝电导率增加，在8 h时OD260处吸光值显著（P<0.05）高于对照（未用生物杀菌剂处理）。PI试验结果表明，生物杀菌剂对致病真菌细胞膜具有明显的损伤作用并通过破坏细胞膜完整性发挥其抑制作用。综上，0.5%苦参碱水剂和10%多抗霉素可湿性粉剂能抑制灰葡萄孢霉和禾谷镰刀菌菌丝生长，可作为灰葡萄孢霉和禾谷镰刀菌侵染引起的线椒病害的生物防治药剂。

关键词: 线椒, 生物杀菌剂, 致病菌, 室内毒力, 贵州