National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, 430070, People's Republic of China.
Laboratory of Risk Assessment for Oilseeds Products (Wuhan), Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, 430061, People's Republic of China.
Microbiome. 2024 Oct 31;12(1):224. doi: 10.1186/s40168-024-01933-7.
Soybean seeds are rich in protein and oil. The selection of varieties that produce high-quality seeds has been one of the priorities of soybean breeding programs. However, the influence of improved seed quality on the rhizosphere microbiota and whether the microbiota is involved in determining seed quality are still unclear. Here, we analyzed the structures of the rhizospheric bacterial communities of 100 soybean varieties, including 53 landraces and 47 modern cultivars, and evaluated the interactions between seed quality traits and rhizospheric bacteria.
We found that rhizospheric bacterial structures differed between landraces and cultivars and that this difference was directly related to their oil content. Seven bacterial families (Sphingomonadaceae, Gemmatimonadaceae, Nocardioidaceae, Xanthobacteraceae, Chitinophagaceae, Oxalobacteraceae, and Streptomycetaceae) were obviously enriched in the rhizospheres of the high-oil cultivars. Among them, Oxalobacteraceae (Massilia) was assembled specifically by the root exudates of high-oil cultivars and was associated with the phenolic acids and flavonoids in plant phenylpropanoid biosynthetic pathways. Furthermore, we showed that Massilia affected auxin signaling or interfered with active oxygen-related metabolism. In addition, Massilia activated glycolysis pathway, thereby promoting seed oil accumulation.
These results provide a solid theoretical basis for the breeding of revolutionary soybean cultivars with desired seed quality and optimal microbiomes and the development of new cultivation strategies for increasing the oil content of seeds. Video Abstract.
大豆种子富含蛋白质和油脂。选育优质种子的品种一直是大豆育种计划的重点之一。然而，改善种子质量对根际微生物群的影响，以及微生物群是否参与决定种子质量，仍然不清楚。在这里，我们分析了 100 个大豆品种的根际细菌群落结构，包括 53 个地方品种和 47 个现代品种，并评估了种子质量性状与根际细菌之间的相互作用。
我们发现，根际细菌结构在地方品种和品种之间存在差异，这种差异与它们的油含量直接相关。有 7 个细菌科（鞘氨醇单胞菌科、真杆菌科、诺卡氏菌科、黄杆菌科、几丁质噬菌科、草酸杆菌科和链霉菌科）在高油品种的根际中明显富集。其中，草酸杆菌科（马西利亚）是由高油品种的根分泌物特异地组装而成，与植物苯丙烷生物合成途径中的酚酸和类黄酮有关。此外，我们表明，马西利亚影响生长素信号或干扰活性氧相关代谢。此外，马西利亚激活糖酵解途径，从而促进种子油脂的积累。
这些结果为培育具有理想种子质量和最佳微生物群的革命性大豆品种提供了坚实的理论基础，并为提高种子含油量的新种植策略的发展提供了理论依据。
