内生真菌对禾草类植物抗旱性的影响

综述了国内外近年来关于内生真菌Neotyphodium对禾草类植物抗旱性方面的研究成果。结果表明:与不带菌禾草相比,带菌禾草的抗逆性强、产量高,特别是内生真菌的侵染可增加宿主植物的抗旱性。据报道,内生真菌主要是通过促进植株根系发育、叶片生长、气孔开闭、渗透调节、抗氧化保护系统等来提高禾草类植物的抗干旱胁迫能力。但也有学者认为并非所有内生真菌对宿主禾草的抗旱性都有增益作用,内生真菌与禾草的共生关系还很大程度上决定于宿主、内生真菌基因型和生境的相互关系。在未来的研究中应以内生真菌-禾草共生体的抗旱机理、生物学特性和群体特征为重点;此外利用真菌-禾草共生体的抗旱特性开展优良牧草草坪草选育,发挥内生真菌在天然草地中的生态作用也是重要的研究方向。

Effect of endophyte infection on drought-resistance of graminaceous grasses

In this paper research progress on effect of endophyte infection on drought-resistance of graminaceous grasses both in China and overseas in recent years was reviewed and key areas for future study were suggested.Experimental researches showed that compared with endophyte free(E-) grass,endophyte infected(E ) grass performed better adaptation to biotic and abiotic stresses,and produced higher herbage dry matter yield,especially endophytes could enhance drought-resistance of grass.The proposed mechanisms improving drought tolerance by endophytes included enhanced root growth,leaf growth,stomatal regulation osmotic adjustment and activity of protective antioxidant.But some researches indicated that not all endophytes had beneficial effects on drought-resistance of the host grass,the relation of endophyte-grass association was also determined by the interaction of the host,endophyte genotype and environmental conditions.Key areas for future research should focus on mechanism of drought-resistance,biological characteristic and ecological characteristic of endophyte-grass association.Additional important research direction was to breed new drought-resistance pasture and turfgrass cultivars by incorporating endophytes into existed cultivars,and to improve ecological functions in native grassland as well.