Song Fang, Bai Fuxi, Wang Juanjuan, Wu Liming, Jiang Yingchun, Pan Zhiyong
Institute of Fruit and Tea, Hubei Academy of Agricultural Sciences, Wuhan 430064, China.
Institute National Agro-Technical Extension and Service Center (NATESC), Ministry of Agriculture, Beijing 100000, China.
Plants (Basel). 2020 Jul 16;9(7):901. doi: 10.3390/plants9070901.
Citrus is vegetatively propagated by grafting for commercial production, and most rootstock cultivars of citrus have scarce root hairs, thus heavily relying on mutualistic symbiosis with arbuscular mycorrhizal fungi (AMF) for mineral nutrient uptake. However, the AMF community composition, and its differences under different citrus scion/rootstock genotypes, were largely unknown. In this study, we investigated the citrus root-associated AMF diversity and richness, and assessed the influence of citrus scion/rootstock genotypes on the AMF community composition in a controlled condition, in order to exclude interferences from environmental factors and agricultural practices. As a result, a total of 613,408 Glomeromycota tags were detected in the citrus roots, and 46 AMF species were annotated against the MAARJAM database. Of these, 39 species belonged to , indicating a dominant role of the AMF in the symbiosis with citrus. PCoA analysis indicated that the AMF community's composition was significantly impacted by both citrus scion and rootstock genotypes, but total samples were clustered according to rootstock genotype rather than scion genotype. In addition, AMF α diversity was significantly affected merely by rootstock genotype. Thus, rootstock genotype might exert a greater impact on the AMF community than scion genotype. Taken together, this study provides a comprehensive insight into the AMF community in juvenile citrus plants, and reveals the important effects of citrus genotype on AMF community composition.
柑橘通过嫁接进行无性繁殖以用于商业生产，并且大多数柑橘砧木品种的根毛稀少，因此在矿质养分吸收方面严重依赖与丛枝菌根真菌（AMF）的共生关系。然而，AMF群落组成及其在不同柑橘接穗/砧木基因型下的差异在很大程度上尚不清楚。在本研究中，我们调查了柑橘根系相关的AMF多样性和丰富度，并在可控条件下评估了柑橘接穗/砧木基因型对AMF群落组成的影响，以排除环境因素和农业实践的干扰。结果，在柑橘根系中总共检测到613,408个球囊菌门标签，并根据MAARJAM数据库注释了46种AMF物种。其中，39种属于，表明在与柑橘的共生关系中占主导地位。主坐标分析表明，AMF群落组成受柑橘接穗和砧木基因型的显著影响，但总样本是根据砧木基因型而非接穗基因型聚类的。此外，AMFα多样性仅受砧木基因型的显著影响。因此，砧木基因型可能比接穗基因型对AMF群落产生更大的影响。综上所述，本研究全面深入地了解了幼年柑橘植株中的AMF群落，并揭示了柑橘基因型对AMF群落组成的重要影响。
