ABSTRACT

In this study, endophytic fungi were isolated from Euphorbia larica Boiss. and their antagonistic potential against phytopathogenic fungi viz. Fusarium sp., Rosellinia sanctae-cruciana and Cladosporium sp. was evaluated using an in vitro confrontation assay. A total of four endophytic fungi were isolated from the roots of E. larica. Among them, two fungal isolates (SQUCC-F1-1 and SQUCC-F6-2) showed inhibitory activity against Fusarium sp. None of the fungal endophytes restricted the growth of Rosellinia sanctae-cruciana and Cladosporium sp. On the basis of multi-gene phylogenetic analysis, these two endophytic fungi were identified as Neocosmospora sp. (SQUCC-F1-1) and Alternaria alternata (SQUCC-F6-2). Scanning electron microscopic observation of hyphae of the phytopathogenic fungi from the dual culture plate revealed morphological abnormalities such as loss of turgidity, shrinkage and disintegration of the hyphae. Analysis of the metabolites produced by these endophytic fungi by GC-MS revealed the existence of various fatty acids, fatty acid methyl esters, hydrocarbons and alkanes, which have been previously demonstrated to have antimicrobial activity. The antagonistic activities of fungal endophytes from E. larica are reported for the first time.

摘要

在这项研究中，从大戟大戟中分离出内生真菌。及其对植物病原真菌的拮抗潜力。镰刀菌属，玫瑰蔷薇科和克鲁索菌属。使用体外对抗试验评估。从毛E的根中分离出总共4种内生真菌。其中，两种真菌分离株（SQUCC-F1-1和SQUCC-F6-2）表现出对镰孢属sp的抑制活性。没有一种真菌内生菌能限制玫瑰茄和十字花科植物的生长。sp。在多基因系统发育分析的基础上，将这两种内生真菌鉴定为新孢子虫。（SQUCC-F1-1）和链格孢菌（SQUCC-F6-2）。扫描电子显微镜观察双培养板中植物病原性真菌的菌丝，发现形态异常，例如菌丝的失去度，收缩和崩解。通过GC-MS对这些内生真菌产生的代谢产物的分析表明，存在多种脂肪酸，脂肪酸甲酯，烃和烷烃，这些物质先前已被证明具有抗菌活性。首次报道了来自E. larica的真菌内生菌的拮抗活性。