Abstract Leaf fall disease of rubber tree caused by Neopestalotiopsis cubana has been reported to negatively impact rubber cultivation in southern Thailand. The aim of this study was to test and select effective fungicides to control this disease. Effects of fungicides, namely metalaxyl, prochloraz, hexaconazole, carbendazim, captan, mancozeb, propineb, aironae, copper oxychloride, sulfur, zinc oxide nanoparticles (ZnO NP), and salicylic acid (SA) were tested for inhibition of conidia germination, mycelial growth, and reduction of disease severity index (%). Systemic fungicide 2 × carbendazim suppressed conidia germination (0.67%) and inhibited mycelial growth (100%) more than the other fungicides or control. Furthermore, 2 × carbendazim showed a lesser disease severity index (36.1%) than those other fungicides and control. Enzyme activities of β-1,3-glucanase, chitinase and peroxidase in carbendazim treated rubber leaves were significantly higher than those observed in control, suggesting that application of carbendazim induced disease resistance in rubber tree leaves. No phytotoxicity (chlorosis, necrosis or leaf blight) was observed in carbendazim treated rubber leaves from level of chlorophyll content. The results reveal that a systemic fungicide, carbendazim, shows antifungal activity against N. cubana, reduces disease development, and induces defense responses in rubber tree leaves.

中文翻译：

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内吸性杀菌剂在橡胶树（巴西橡胶树）抗真菌活性和诱导防御反应中的作用，对抗由古巴新疫霉引起的落叶病

摘要 据报道，由 Neopestalotiopsis cubana 引起的橡胶树落叶病对泰国南部的橡胶种植产生了负面影响。本研究的目的是测试和选择有效的杀菌剂来控制这种病害。测试了杀菌剂，即甲霜灵、丙氯灵、己唑菌、多菌灵、克菌丹、代森锰锌、丙磺草、氧氯化铜、硫磺、氧化锌纳米颗粒 (ZnO NP) 和水杨酸 (SA) 对分生孢子萌发、菌丝体生长的抑制作用, 以及疾病严重程度指数 (%) 的降低。内吸性杀菌剂 2 × 多菌灵抑制分生孢子萌发 (0.67%) 和抑制菌丝体生长 (100%) 比其他杀菌剂或对照更多。此外，与其他杀菌剂和对照相比，2×多菌灵显示出较低的疾病严重程度指数（36.1%）。多菌灵处理的橡胶叶片中β-1,3-葡聚糖酶、几丁质酶和过氧化物酶的酶活性显着高于对照，表明施用多菌灵诱导了橡胶树叶的抗病性。从叶绿素含量水平来看，在多菌灵处理的橡胶叶中未观察到植物毒性（萎黄病、坏死或叶枯病）。结果表明，内吸性杀菌剂多菌灵对古巴猪瘟显示出抗真菌活性，减少疾病发展，并诱导橡胶树叶的防御反应。从叶绿素含量水平观察，在多菌灵处理的橡胶叶中观察到坏死或叶枯病。结果表明，内吸性杀菌剂多菌灵对古巴猪瘟显示出抗真菌活性，减少疾病发展，并诱导橡胶树叶的防御反应。从叶绿素含量水平观察，在多菌灵处理的橡胶叶中观察到坏死或叶枯病。结果表明，内吸性杀菌剂多菌灵对古巴猪瘟显示出抗真菌活性，减少疾病发展，并诱导橡胶树叶的防御反应。