禾草内生真菌研究及应用进展

内生真菌感染大部分禾草形成互惠共生体,提高共生体对环境适应性,并进而对动物、微生物以及整个生态系统产生广泛的影响,使该领域成为近年来研究的热点问题。分子生物学技术、基因组学、蛋白组学和代谢组学以及相应的信息生物学技术的应用加快了禾草内生真菌的研究,尤其是内生真菌全基因组序列的测定,明确了次生代谢物多样性及其与基因的关系,鉴定相关的功能基因和蛋白,基因敲除技术阐释了维持内生真菌与寄主动态平衡的分子机制。利用基因组学等技术筛选对家畜无毒的内生真菌菌株, 通过接种技术建立新的既具有抗逆性,又对家畜无毒的禾草-内生真菌共生体,提高禾草的品质并确保对动物的安全性,在牧草及草坪草育种上获得了巨大成功。但是内生真菌的寄主特异性限制了内生真菌可利用的范围,因此后续应继续利用基因组学和代谢组学新技术深入研究内生真菌与寄主相互作用的机制,利用基因工程技术人工创造无毒菌株,克服共生体创制的瓶颈。本研究旨在对以上内容进行综述,以期为更广泛利用内生真菌进行牧草和草坪草育种奠定基础。

Advances in research on grass endophytes in agricultural systems and applications in forage breeding

The Epichloё endophyte forms mutually beneficial associations with its hosts, which enhance their survival under abiotic and biotic stresses. Modern techniques in molecular biology, genomics, proteomics, metabolomics, and bioinformatics have accelerated research on endophytes. The diversity of secondary metabolites and the genes related to their biosynthesis have been identified and the molecular mechanisms of mutualism between the Epichloё endophyte and its hosts have been clarified. These endophytes are widely utilized in agriculture as they are animal-safe grass endophytes that improve the growth and stress resistance of their hosts, leading to increased pasture persistence, sustainability, and production. Thus, several Epichloё endophytes have been developed and commercialized. In this paper, we review recent research on the interactions between grasses and endophytes, and the effects of endophytes on livestock and on microbial and pasture ecosystems. We also discuss the selection of endophyte strains and forage breeding based on multidisciplinary research.