橙黄乳菇对马尾松和华山松幼苗生长及根系代谢物的调控

Regulation of Lactarius akahatsu on the Growth and Root Metabolites of Pinus massoniana and Pinus armandii Seedlings

【目的】探究接种橙黄乳菇对马尾松和华山松幼苗生长、根系发育及代谢物的影响,为橙黄乳菇与2种松树菌根化苗木培育及共生栽培提供参考。【方法】以马尾松和华山松幼苗为研究对象,基于大棚盆栽试验,测定分析接种和未接种橙黄乳菇的2种松树幼苗菌根侵染情况、地上和地下生长指标、根系构型性状(根长、表面积、根体积、根尖数、分叉数)、形态性状(比根长、组织密度、比表面积)及根系代谢物差异。【结果】橙黄乳菇与2种松树幼苗均形成明显的菌根形态,并有较高的菌根侵染率和菌根依赖性。接种橙黄乳菇对2种松树幼苗生长具有一定促进作用,但存在差异,接种后马尾松幼苗株高和地上部分干质量显著增加,华山松幼苗株高和地下部分干质量显著增加,2种松树幼苗总根长、根表面积、根体积、根尖数和分叉数均明显提高,根系活力和阳离子交换量降低。接种橙黄乳菇明显影响2种松树幼苗根系代谢物含量,接种后马尾松幼苗根系总酚和总黄酮质量分数降低,总三萜、总生物碱和总甾醇质量分数升高,华山松幼苗根系代谢物变化趋势与马尾松相反。【结论】接种橙黄乳菇可改善2种松树幼苗根系形态、提高生物量、影响根系主要代谢物含量,在松树菌根化苗木培育即外生菌根真菌共生栽培方面具有可行性。

【Objective】The study is aimed to investigate the effects of Lactarius akahatsu inoculation on the growth,root development,and metabolites of Pinus massoniana and Pinus armandii seedlings,and to provide a scientific basis to cultivate pine mycorrhizal seedlings and symbiotic cultivation of Lactarius akahatsu.【Method】Potted seedlings of Pinus massoniana and Pinus armandii were placed in the greenhouse and applied with two treatments of Lactarius akahatsu inoculation and noninoculation,the difference in the mycorrhizal colonization rate and mycorrhizal dependency,shoot and root growth indicators,the root architecture traits(total root length,root surface area,root volume,root tips,bifurcation),the root morphology traits(specific root length,root tissue density,specific root surface area)and main root metabolites were studied.【Result】Evident mycorrhizal morphology of the Lactarius akahatsu was formed in the seedlings of the two pines,and displayed a high mycorrhizal colonization rate and mycorrhizal dependency.The inoculation of Lactarius akahatsu promoted the growth of seedlings to a certain extent,but significant differences were found between the two species.Lactarius akahatsu inoculation significantly increased the plant seedling’s height and dry aboveground weight of Pinus massoniana seedlings,whereas the plant height and dry underground weight of Pinus armandii.The total root length,root surface area,root volume,root tip number,and bifurcation of the two pine species increased by Lactarius akahatsu inoculation,while root vigor and cation exchange capacity decreased.Inoculation with Lactarius akahatsu significantly affected the content of main metabolites in the roots of the two pine species.After Lactarius akahatsu inoculation,the total phenols content and total flavonoid content in the roots of Pinus massoniana seedlings decreased,while the total triterpenoid content,total alkaloid content and total sterol content increased.The trends in metabolites in the root of Pinus armandii seedlings was opposite to that of Pinus massoniana seedlings.【Conclusion】Lactarius akahatsu inoculation improves the root morphology and biomass of the seedlings,and affects the content of main metabolites in the roots,and therefore Lactarius akahatsu inoculation is feasible to cultivate pine mycorrhizal seedlings and symbiotic cultivation of ectomycorrhizal fungi.