通过构建单一内生真菌-石蒜〔Lycoris radiata (L’Hér.) Herb.〕无菌组培苗互作体系，探究亚虫草属(Metacordyceps Sung)内生真菌LrRF8对石蒜叶、鳞茎、根干质量及NO、H2O2、IAA、SA、GA积累及石蒜科生物碱合成关键基因表达的影响，探究LrRF8促进石蒜中生物碱积累的机制。结果表明：与对照(未接菌)组相比，接种LrRF8显著提高了叶和鳞茎中加兰他敏及根中水仙环素、石蒜碱和加兰他敏的含量。进一步研究发现，接种LrRF8能够诱导石蒜不同组织中NO和H2O2的差异迸发，其诱导效果在根中最显著；同时，接种LrRF8引起了IAA、SA、GA在石蒜不同组织中的差异积累，主要促进了叶中GA及根中IAA和SA的积累。此外，接种LrRF8 7 d显著提高了石蒜叶、鳞茎中PAL和OMT及根中PAL的相对表达量，接种LrRF8 14 d显著提高了叶中PAL和CYP96T1，鳞茎中PAL及根中PAL、TYDC、CYP96T1的相对表达量。从整株看，施加外源信号分子和植物激素能够提高石蒜中生物碱的积累，并且外源施加SNP提高了石蒜中CYP96T1的相对表达量，外源施加H2O2提高了TYDC、OMT和CYP96T1的相对表达量，外源施加IAA提高了TYDC的相对表达量，外源施加SA提高了PAL和CYP96T1的相对表达量，外源施加GA提高了OMT和CYP96T1的相对表达量。综上所述，相较于盆栽体系，本研究构建的单一内生真菌-石蒜无菌组培苗互作体系排除了环境微生物的干扰，证实接种LrRF8有利于促进石蒜中生物碱的积累，其中NO和H2O2及IAA、SA和GA信号在基因表达层面发挥重要调控作用。

The effects of endophytic fungus Metacordyceps Sung LrRF8 on dry mass of leaves, bulbs, and roots of Lycoris radiata (L‘Hér.) Herb., accumulation of NO, H2O2, IAA, SA, and GA, and expression of key genes involved in Amaryllidaceae alkaloid biosynthesis were investigated by establishing a interaction system of single endophytic fungus-sterile tissue-cultured L. radiata seedlings, and the mechanism by which LrRF8 promotes alkaloid accumulation in L. radiata was elucidated. The results show that compared with the control (non-inoculation) group, LrRF8 inoculation significantly increases the contents of galanthamine in leaves and bulbs and narciclasine, lycorine, and galanthamine in roots. Further studies reveal that LrRF8 inoculation can induce differential bursts of NO and H2O2 in different tissues of L. radiata, with the most significant induction effect in roots; meanwhile, LrRF8 inoculation causes differential accumulation of IAA, SA, and GA in different tissues of L. radiata, primarily promotes GA accumulation in leaves and IAA and SA accumulation in roots. Additionally, LrRF8 inoculation for 7 d significantly increases the relative expression of PAL and OMT in leaves and bulbs, and PAL in roots of L. radiata; LrRF8 inoculation for 14 d significantly increases the relative expression of PAL and CYP96T1 in leaves, PAL in bulbs, and PAL, TYDC and CYP96T1 in roots. In the whole seedling, exogenous application of signaling molecules and plant hormones can promote alkaloid accumulation in L. radiata, the exogenous application of SNP increases the relative expression of CYP96T1, exogenous application of H2O2 upregulates those of TYDC, OMT, and CYP96T1, exogenous application of IAA elevates that of TYDC, exogenous application of SA enhances those of PAL and CYP96T1, and exogenous application of GA promotes those of OMT and CYP96T1. In conclusion, compared with pot culture systems, the single endophytic fungus-sterile tissuecultured L. radiata seedlings interaction system established in this study eliminates the interference from environmental microorganisms and demonstrates that LrRF8 inoculation promotes alkaloid accumulation in L. radiata, among which NO, H2O2, and IAA, SA and GA signals play crucial regulatory roles at gene expression level.