内生真菌Subsessila turbinata RG170对肉桂幼苗生理特性及次生代谢的影响

Effects of endophytic fungus Subsessila turbinata RG170 on physiological characteristics and secondary metabolite in Cinnamomum cassia seedlings

关键词:  肉桂, 内生真菌, 促生特性, 生理特性, 肉桂醛, 微生物菌剂

Key words:  Cinnamomum cassia, endophytic fungi, growth-promoting properties, physiological characteristics, cinnamaldehyde, microbial agents

摘要:

为探究内生真菌RG170(Subsessila turbinata)对肉桂(Cinnamomum cassia)幼苗生理特性及次生代谢产物积累的影响,该研究以分离自健康肉桂叶片的内生真菌RG170为对象,通过体外促生活性测定(包括溶磷、解钾和固氮能力)及无菌共培养体系,评价其促生潜力,并进一步采用盆栽试验验证其对肉桂生长与代谢的实际效应。结果表明:(1)在无菌共培养条件下,接种RG170显著促进了肉桂幼苗的生长,与对照组相比,株高、鲜重、侧根数和叶面积分别提高了15.4%、54.2%、40.1%和29.5%,除株高外,其他均达到显著性差异。(2)盆栽试验中,接种RG170显著提高了肉桂幼苗地下部分的干物质量。(3)与对照组相比,接种RG170幼苗的叶片可溶性糖和可溶性蛋白含量分别显著增加51.9%和63.8%,超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性分别显著提升66.5%和279.0%。(4)接种还显著提高了叶片总黄酮和总酚含量,增幅分别为115.3%和113.9%; 叶片和茎皮中肉桂醇、肉桂酸以及肉桂醛含量均显著上升,其中肉桂醛含量分别提高35.5%和68.8%。综上,接种具有多种促生特性的RG170菌株,不仅能促进肉桂幼苗生长、提高其生理活性,还能促进总黄酮、肉桂醛等关键次生代谢物的积累,为肉桂微生物菌剂的开发提供了依据。

Abstract:

To investigate the effects of the endophytic fungus RG170(Subsessila turbinata)on the physiological characteristics and secondary metabolite accumulation of Cinnamomum cassia seedlings, the endophytic fungus RG170, isolated from healthy leaves of C. cassia, was used as the research subject. The plant growth-promoting potential was evaluated through in vitro assays assessing phosphate solubilization, potassium solubilization, and nitrogen fixation, as well as through a sterile co-culture system. Pot experiments were further conducted to verify its actual effects on C. cassia growth and metabolism. The results were as follows:(1)Under sterile co-culture conditions, inoculation with RG170 significantly promoted the growth of C. cassia seedlings. Compared with the control, plant height, fresh weight, number of lateral roots, and leaf area increased by 15.4%, 54.2%, 40.1%, and 29.5%, respectively, with all parameters except plant height showing significant differences.(2)In pot experiments, inoculation with RG170 significantly increased the dry biomass of the underground parts of C. cassia seedlings.(3)Compared with the control, the RG170-inoculated seedlings exhibited significantly higher levels of soluble sugars and soluble proteins in leaves, with increases of 51.9% and 63.8%, respectively, while the activities of superoxide dismutase(SOD)and catalase(CAT)were significantly enhanced by 66.5% and 279.0%, respectively.(4)Inoculation also significantly increased total flavonoid and total phenolic contents in leaves by 115.3% and 113.9%, respectively; the contents of cinnamyl alcohol, cinnamic acid, and cinnamaldehyde in both leaves and stem bark were significantly elevated, with cinnamaldehyde content increasing by 35.5% and 68.8%, respectively. In conclusion, inoculation with the RG170 strain, which possesses multiple growth-promoting traits, not only promotes the growth and enhances the physiological activity of C. cassia seedlings but also facilitates the accumulation of key secondary metabolites, such as total flavonoids and cinnamaldehyde. This study provides a basis for the development of microbial inoculants for C. cassia.