Mycorrhization of strawberry plantlets potentiates the synthesis of phytochemicals during ex vitro acclimatization

ABSTRACT. Ex vitro strawberry plantlets from micropropagation and coinoculated with arbuscular mycorrhizal fungi (AMF) and biochar can provide beneficial health effects. In the present study, we evaluated the effects of different proportions of biochar in the presence and absence of AMF on the production of secondary metabolites in the leaves and roots of strawberry plantlets during ex vitro acclimatization. Additionally, the enzymatic activity of the substrate enriched with AMF and biochar was analyzed. The experiment consisted of the control (absence of the mycorrhizal community) and four biochar proportions (0, 3, 6, and 9% of the volume of the container) coinoculated with AMF. Plantlets produced on substrates enriched with AMF showed higher levels of polyphenols, flavonoids, phenolic acids, and tannins in the tissues analyzed than control plantlets. The combination of AMF and 9% biochar increased the content of total flavonoids in the leaves of strawberry plantlets and increased the activity of phosphatase. The substrate with up to 6% biochar and mycorrhizae showed increased β-glucosidase activity. In conclusion, mycorrhizae are excellent tools to improve the phytochemical quality of strawberry plantlets acclimatized ex vitro. The association between host plants, mycorrhizal symbionts, and bioactivators of these fungi potentiates properties beneficial to health, which can be exploited efficiently in sustainable agriculture.

摘要：经微繁殖（micropropagation）获得的草莓组培幼苗，若与丛枝菌根真菌（arbuscular mycorrhizal fungi，AMF）及生物炭（biochar）共接种，可产生有益的健康效应。本研究评估了在接种与不接种AMF的条件下，不同比例生物炭对离体移栽驯化过程中草莓幼苗叶片与根系次生代谢产物生成的影响。此外，本研究还分析了接种AMF并添加生物炭的栽培基质的酶活性。本实验设置了对照组（无菌根群落）与4组不同生物炭添加比例（占容器体积的0%、3%、6%、9%）的处理组，所有处理组均与AMF共接种。结果显示，接种AMF的基质培育的草莓幼苗，其被测组织中的多酚类、黄酮类、酚酸类及单宁类物质含量均高于对照组幼苗。AMF与9%生物炭的组合可提升草莓幼苗叶片的总黄酮含量，并增强磷酸酶活性。添加6%及以下比例生物炭并接种AMF的基质，其β-葡萄糖苷酶活性有所提升。综上，菌根真菌是提升离体移栽驯化草莓幼苗植物化学品质的优良工具。宿主植物、菌根共生体与这类真菌的生物活化剂之间的协同作用，可强化有益健康的特性，该成果可在可持续农业中得到高效应用。