ABSTRACT

Endophytic fungi usually establish a symbiotic relationship with the host plant and affect its growth. In order to evaluate the impact of endophytic fungi on the Chinese herbal medicinal plant Houttuynia cordata Thunb., three endophytes isolated from the rhizomes of H. cordata, namely Ilyonectria liriodendra (IL), unidentified fungal sp. (UF), and Penicillium citrinum (PC), were co-cultured individually with H. cordata in sterile soil for 60 days. Analysis of the results showed that the endophytes stimulated the host plant in different ways: IL increased the growth of rhizomes and the accumulation of most of the phenolics and volatiles, UF promoted the accumulation of the medicinal compounds afzelin, decanal, 2-undecanone, and borneol without influencing host plant growth, and PC increased the fresh weight, total leaf area and height of the plants, as well as the growth of the rhizomes, but had only a small effect on the concentration of major secondary metabolites. Our results proved that the endophytic fungi had potential practical value in terms of the production of Chinese herbal medicines, having the ability to improve the yield and accumulation of medicinal metabolites.

摘要

内生真菌通常与寄主植物建立共生关系并影响其生长。为了评估内生真菌对中草药植物鱼腥草的影响，从鱼腥草的根茎中分离出三种内生菌，即Ilyonectria liriodendra (IL)，未鉴定的真菌 sp。(UF) 和柑橘青霉(PC) 分别与H. cordata共培养在无菌土壤中放置 60 天。结果分析表明，内生菌以不同的方式刺激寄主植物：白介素促进根茎的生长和大部分酚类物质和挥发物的积累，超滤促进药用化合物afzelin、癸醛、2-十一酮和冰片不影响寄主植物生长，而PC增加了植物的鲜重、总叶面积和高度，以及根茎的生长，但对主要次生代谢产物的浓度影响不大。我们的研究结果证明，内生真菌在中药材生产方面具有潜在的实用价值，具有提高药用代谢产物产量和积累的能力。