In vitro effects of different fungicides (botanicals, chemicals, and bio-agents) on mycelial growth of Sclerotium rolfsii causing betel vine (Piper betle L) foot rot disease in Bangladesh

Sclerotium rolfsii Sacc causing foot rot disease which is one of the major limiting factor for betelvine cultivation in Bangladesh. In this study, we have evaluated the antifungal activity of medicinal plant extracts, chemical fungicides, and antagonistic fungal isolates on mycelial growth of Sclerotium rolfsii. Among the tested medicinal plants, the highest percent inhibition was exhibited by leaf extracts of Datura metel and Lowsonia inermis L. in all three solvents (aqueous; ethanol and acetone) and concentrations. The chemicals fungicides - Bavistin DF (Carbendazim) and Dithane M-45 (Mancozeb), effectively inhibited the growth of the S. rolfsii. However, at lower concentrations, other tested fungicides were found to be less effective. Among the six biological control agents, Trichoderma harzianum showed the highest percent inhibition of radial growth of S. rolfsii. The secondary metabolites of T. harzianum and T. viride significantly reduced the mycelial growth of S. rolfsii.

齐整小核菌（Sclerotium rolfsii Sacc）引发的基腐病，是孟加拉国蒌叶栽培的主要限制因素之一。本研究针对齐整小核菌的菌丝生长，评估了药用植物提取物、化学杀菌剂及拮抗真菌分离物的抗真菌活性。在所测试的药用植物中，曼陀罗（Datura metel）与散沫花（Lawsonia inermis L.，原文拼写为Lowsonia，应为Lawsonia）的叶片提取物在三种溶剂（水、乙醇及丙酮）及所有浓度梯度下，均表现出最高的菌丝生长抑制率。化学杀菌剂中，宝丽安DF（多菌灵，Carbendazim）和大生M-45（代森锰锌，Mancozeb）可有效抑制齐整小核菌的菌丝生长。但在低浓度条件下，其余供试杀菌剂的抑菌效果相对较弱。在6种生防菌剂中，哈茨木霉（Trichoderma harzianum）对齐整小核菌的菌丝径向生长抑制率最高。哈茨木霉与绿色木霉（T. viride）的次生代谢产物均可显著抑制齐整小核菌的菌丝生长。