山东省不同地区蔬菜菌核病菌对四霉素的敏感性

Sensitivity of Sclerotinia sclerotiorum from vegetables to tetramycin in Shandong Province

采用菌丝生长速率法测定了四霉素对采自山东省不同地区不同蔬菜作物的151株菌核病菌的毒力作用,同时比较了其对蔬菜菌核病菌不同生育阶段的抑制活性,并通过离体叶片法评价了四霉素对蔬菜菌核病的防治效果。结果表明：菌核病菌对四霉素比较敏感,敏感性频率呈单峰正态分布,151株病菌菌丝生长的平均EC50值为（0.29±0.01）μg/mL,该值可作为蔬菜菌核病菌对四霉素的敏感基线。此外,经四霉素处理后,该病菌的菌核数量以及干重明显降低,菌核明显变小;2μg/mL的处理对菌核萌发的抑制率达到100.00%。离体黄瓜叶片接种试验表明,四霉素对菌核病具有较好的保护和治疗效果,且保护作用较为显著。在质量浓度为20μg/mL时,四霉素对该病的防效显著高于对照药剂多菌灵和异菌脲。因此,四霉素具有防治蔬菜菌核病的潜在价值,可进一步通过田间试验验证其应用效果。

The sensitivities of 151 Sclerotinia sclerotiorum isolates from various vegetables in Shandong Provice to tetramycin were determined by the mycelial growth rate method. Furthermore, the inhibitory activities of tetramycin against sclerotial production and sclerotial germination were also determined. The efficacy of tetramycin against S. sclerotiorum was assessed on detached cucumber leaves. The results showed that 151 S. sclerotiorum isolates were all sensitive to tetramycin, with the mean EC50 values of（0.29 ± 0.01） μg/mL. And the frequency distribution of sensitivities was a unimodal curve, which indicated that the averaged EC50 values can be regarded as the sensitivity baseline of tetramycin against S. sclerotiorum from vegetables. In addition, after treated with tetramycin, the number and dry weight of sclerotia was significantly decreased, and the shape of sclerotia also became smaller. Using tetramycin at 2 μg/mL can completely inhibit the myceliogenic germination of sclerotia. The results of in vitro leaf tests showed that tetramycin had protective activity and curative activity in the control of sclerotinia stem rot, and the protective activity was satisfactory.Applying tetramycin at 20 μg/mL, the efficacy against S. sclerotiorum was significantly higher than that of carbendazim and iprodione. In conclusion, good bioactivity of tetramycin against S. sclerotiorum demonstrates its potential application in the control of sclerotinia stem rot in the future.