Botany Department, Faculty of Science, Tanta University, Egypt.
Microb Pathog. 2017 Dec;113:135-143. doi: 10.1016/j.micpath.2017.10.041. Epub 2017 Oct 23.
The present study represents, for the first time, the detailed studies about the hyphal interactions of Aspergillus piperis, as a new antagonist, against some isolated plant pathogenic fungi (Alternaria alternata, Alternaria solani, Botrytis cinerea, Sclerotium cepivorum and Sclerotinia sclerotiorum) in vitro. The bio-controlling capability of A. piperis against the tested phytopathogens was tested using the dual culture method. This experiment revealed that A. piperis had antagonistic activity and reduced the growth of the tested phytopathogens and grew over their mycelia in the paired plates. Also, several antagonistic mechanisms were recorded, in this study, between A. piperis and the tested phytopathogens using the microscopic examination. The bio-controlling activity and the antagonistic mechanisms exhibited by the new antagonist, A. piperis were compared with those obtained by the common antagonist, Trichoderma harzianum against the same phytopathogens. The obtained results showed that, A. piperis was more effective than T. harzianum in inhibiting all the tested species in the dual culture plates. The best result was 81.85% inhibition percentage against S. sclerotiorum by A. piperis while, T. harzianum exhibits only 45.18%. Moreover, several antagonistic mechanisms and hyphal interactions were investigated among the hyphae of both A.piperis and T. harzianum and the hyphae of the tested phytopathogens. These mechanisms were summarized as; mycoparasitism (coiling and penetration of the hyphae) and antibiosis in the form of lysis of the hyphal cells and spores, denaturation and breaking of the hyphae. The indirect interaction (antibiosis) and the direct mycoparasitism were observed by A. piperis against all the tested phytopathogens, but it attacked the hyphae and conidiophores of A. alternata by only the antibiosis interaction. The microscopic examination revealed also that T. harzianum attacked the tested phytopathogens by both antibiosis and mycoparasitism except against A. solani which attacked only by mycoparasitism.
本研究首次详细研究了作为新拮抗物的胡椒曲霉（Aspergillus piperis）与几种分离的植物病原菌（Alternaria alternata、Alternaria solani、Botrytis cinerea、Sclerotium cepivorum 和 Sclerotinia sclerotiorum）在体外的菌丝相互作用。使用双层培养法测试了 A. piperis 对测试植物病原菌的生物防治能力。实验表明，A. piperis 具有拮抗活性，可以减少测试植物病原菌的生长，并在配对平板上生长在它们的菌丝上。此外，在这项研究中，通过显微镜检查记录了 A. piperis 与测试植物病原菌之间的几种拮抗机制。将新拮抗物 A. piperis 的生物防治活性和拮抗机制与常见拮抗物哈茨木霉（ Trichoderma harzianum ）对相同植物病原菌的活性和机制进行了比较。结果表明，在双层培养平板中，A. piperis 比 T. harzianum 更有效地抑制所有测试物种。对 S. sclerotiorum 的最佳抑制率为 81.85%，而 T. harzianum 的抑制率仅为 45.18%。此外，还研究了 A.piperis 和 T. harzianum 的菌丝以及测试植物病原菌的菌丝之间的几种拮抗机制和菌丝相互作用。这些机制总结如下：菌丝寄生（菌丝缠绕和穿透）和抗生作用，表现为菌丝细胞和孢子的溶解、变性和断裂。间接相互作用（抗生作用）和直接菌丝寄生作用被 A. piperis 观察到对所有测试的植物病原菌，但它仅通过抗生作用攻击 A. alternata 的菌丝和分生孢子。显微镜检查还表明，T. harzianum 通过抗生作用和菌丝寄生作用攻击测试植物病原菌，除了仅通过菌丝寄生作用攻击 A. solani 之外。
