瘤菌根菌对铁皮石斛根系形态的影响及其共生关系的研究

Effect of Epulorhiza sp. on Root Morphology of Dendrobium officinale and Their Symbiotic Relationship

为了解瘤菌根菌(Epulorhizasp.)与铁皮石斛(Dendrobiumofficinale)根系的共生关系及其对根系农艺性状的影响,用液体培养瘤菌根菌浇灌无菌盆栽铁皮石斛苗根部共培养,观察石斛根的表型和超微结构变化,并用分子检测鉴定菌丝是否定殖根中。结果表明,瘤菌根菌菌丝能侵入根的皮层细胞,诱导生成菌丝团形成共生关系。共生后的菌丝能提高IAA含量,诱导根系结构发生改变生成侧根,增大了根系体积,促进根系的生长并显著提高根系活力。瘤菌根菌与铁皮石斛根共培养后建立共生关系形成菌根且能定殖于根中,诱导根系结构的变化,侧根的形成对石斛生长具有重要作用。

In order to understand the symbiotic relationship between Epulorhiza sp. and the roots of Dendrobium officinale, and also to make certain the influence of Epulorhiza sp. on root morphology, the roots of D. officinale were irrigated with liquid cultured Epulorhiza sp., the changes in phenotype and ultrastructure of roots were observed after three months. The results showed that the cortical cells of root were invaded by mycelia, which induced the formation of mycelium group to form a symbiotic relationship between Epulorhiza sp. and the roots. The content of IAA in root increased after co-cultured with Epulorhiza sp., and the lateral roots were induced for increasing root volume, as well as the root vitality was significantly improved. Therefore, Epulorhiza sp. co-cultured with the roots of D. officinale not only could generate mycorrhizal to establish a symbiotic relationship, but also the symbiotic mycelium could colonize in roots, induced the changes in root structure, and the formation of lateral root played an important role in growth of D. officinale.