Ye Yueyu, Li Shiqing, Li Xiaomei, Chen Man, Chen Haimin, Yuan Qiang, Yang Dongfeng, Li Meiya, Jiang Fusheng, Zhang Chunchun
College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, 310053, China.
Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, 310018, China.
Fungal Biol. 2025 May;129(3):101553. doi: 10.1016/j.funbio.2025.101553. Epub 2025 Feb 28.
The orchids usually coexist with mycorrhizal fungi during their growth and development. Numerous studies have substantiated the pivotal regulatory role of Tulasnella sp. mycorrhizal fungi in the germination and growth of orchid seeds. However, there remains a dearth of research elucidating the effects and underlying mechanisms of Tulasnella sp. on the growth, development, and metabolite accumulation in Bletilla striata seedlings. In the current study, metabolomics and transcriptomic analysis were used to reveal the key role of the mycorrhizal fungus Tulasnella sp.BJ1 in the growth and accumulation of secondary metabolites in B. striata. The results demonstrated that the application of BJ1 significantly enhanced the growth and development of B. striata seedlings. In September, the plant weight, tuber diameter, and tuber weight in the BJ1 treatment group reached 44.27 ± 6.79 g, 6.13 ± 0.53 cm, and 23.35 ± 3.06 g, respectively, surpassing those in the control group. The polysaccharide content in the BJ1 treatment group and control group peaked in June, reaching 14.91 ± 2.26 % and 14.38 ± 0.25 %, respectively. Total phenol content in both groups decreased in May and June, and the total phenol content in BJ1 treatment group was significantly lower than that in control group. The significant decrease observed in total phenol content during May and June may be attributed to an increase in proportion of polysaccharides promoted by BJ1. The transcriptome results showed that BJ1 upregulated polysaccharide biosynthesis-related genes, such as mannose phosphatase, transferase, mannose 6-phosphate isomerase, hexokinase, fructose kinase, and glucose 6-phosphate isomerase, as well as genes involved in stilbenes biosynthesis, including hydroxycinnamyltransferase and transcinnamate 4-monooxygenase. Metabolomics data indicated that the content of mannose and seven stilbene compounds in the tubers increased significantly after BJ1 treatment. Interestingly, the accumulation of these compounds corresponds to the pathway of upregulated genes. These findings suggest that an upregulation in mannose synthesis may facilitate the accumulation of polysaccharides in B. striata. Therefore, the current study uncovered that the mycorrhizal fungus Tulasnella sp. BJ1 can not only promote the growth and development of B. striata seedlings and increase tuber yield but also promote the accumulation of polysaccharides and stilbenes.
兰花在其生长发育过程中通常与菌根真菌共存。大量研究证实了土氏菌属菌根真菌在兰花种子萌发和生长中的关键调节作用。然而，关于土氏菌属对白及幼苗生长、发育和代谢产物积累的影响及其潜在机制的研究仍然匮乏。在本研究中，采用代谢组学和转录组学分析来揭示菌根真菌土氏菌BJ1在白及次生代谢产物生长和积累中的关键作用。结果表明，BJ1的应用显著促进了白及幼苗的生长发育。9月，BJ1处理组的植株重量、块茎直径和块茎重量分别达到44.27±6.79 g、6.13±0.53 cm和23.35±3.06 g，超过了对照组。BJ1处理组和对照组的多糖含量在6月达到峰值，分别为14.91±2.26%和14.38±0.25%。两组的总酚含量在5月和6月均下降，且BJ1处理组的总酚含量显著低于对照组。5月和6月总酚含量显著下降可能归因于BJ1促进了多糖比例的增加。转录组结果显示，BJ1上调了多糖生物合成相关基因，如甘露糖磷酸酶、转移酶、甘露糖6-磷酸异构酶、己糖激酶、果糖激酶和葡萄糖6-磷酸异构酶，以及参与芪类生物合成的基因，包括羟基肉桂酰转移酶和反式肉桂酸4-单加氧酶。代谢组学数据表明，BJ1处理后块茎中甘露糖和七种芪类化合物的含量显著增加。有趣的是，这些化合物的积累与上调基因的途径相对应。这些发现表明，甘露糖合成的上调可能促进白及中多糖的积累。因此，本研究发现菌根真菌土氏菌BJ1不仅能促进白及幼苗的生长发育并提高块茎产量，还能促进多糖和芪类化合物的积累。
