Thakur Abhinay, Kaur Sanehdeep, Kaur Amarjeet, Singh Varinder
Department of Zoology, Guru Nanak Dev University, Amritsar (Punjab), India.
Environ Entomol. 2013 Apr;42(2):240-6. doi: 10.1603/EN12001.
Endophytic fungi, which live within host plant tissues without causing any visible symptom of disease, are important mediators of plant-herbivore interactions. These endophytes enhance resistance of host plant against insect herbivores mainly by productions of various alkaloid based defensive compounds in the plant tissue or through alterations of plant nutritional quality. Two endophytic fungi, i.e., Nigrospora sp. and Cladosporium sp., were isolated from Tinospora cordifolia (Thunb.) Miers, a traditional indian medicinal plant. Cauliflower (Brassica oleracea L.) plants were inoculated with these two endophytic fungi. The effect of endophyte infected and uninfected cauliflower plants were measured on the survival and development of Spodoptera litura (Fab.), a polyphagous pest. Endophyte infected cauliflower plants showed resistance to S. litura in the form of significant increase in larval and pupal mortality in both the fungi. Inhibitory effects of endophytic fungi also were observed on adult emergence, longevity, reproductive potential, as well as hatchability of eggs. Thus, it is concluded that antibiosis to S. litura could be imparted by artificial inoculation of endophytes and this could be used to develop alternative ecologically safe control strategies.
内生真菌生活在宿主植物组织内，不会引起任何明显的病害症状，是植物与食草动物相互作用的重要调节者。这些内生真菌主要通过在植物组织中产生各种基于生物碱的防御化合物或改变植物的营养质量，来增强宿主植物对昆虫食草动物的抗性。从印度传统药用植物心叶青牛胆（Tinospora cordifolia (Thunb.) Miers）中分离出两种内生真菌，即黑孢霉属（Nigrospora sp.）和枝孢属（Cladosporium sp.）。用这两种内生真菌接种花椰菜（Brassica oleracea L.）植株。测定了内生真菌感染和未感染的花椰菜植株对多食性害虫斜纹夜蛾（Spodoptera litura (Fab.)）存活和发育的影响。内生真菌感染的花椰菜植株对斜纹夜蛾表现出抗性，两种真菌处理下幼虫和蛹的死亡率均显著增加。还观察到内生真菌对成虫羽化、寿命、繁殖潜力以及卵的孵化率有抑制作用。因此，得出结论：人工接种内生真菌可赋予对斜纹夜蛾的抗菌性，这可用于制定替代性的生态安全控制策略。
