A significant difference was observed in seed coat structure and phytochemical properties between brown and black seeds of S. glauca. Total 9 phyla, 13 classes, 31 orders, 53 families, 102 genera were identified in the dimorphic seeds. The dominant phyla were Proteobacteria, Firmicutes, and Actinobacteria. The results showed that seed dimorphism had little impact on the diversity and richness of endophytic bacterial communities but significantly differs in the relative abundance of the bacterial community between brown and black seeds. At the phylum level, Actinobacteria tend to be enriched significantly in brown seeds. At the genus level, Rhodococcus, Ralstonia, Pelomonas and Bradyrhizobium tend to be enriched significantly in brown seeds, while Marinilactibacillus was mainly found in black seeds. Besides, brown seeds harbored a large number of bacteria with plant-growth-promoting traits, whereas black seeds presented bacteria with enzyme activities (i.e., pectinase, cellulolytic and xylanolytic activities).
The endophytic bacterial community compositions were significantly different between dimorphic seeds of Suaeda glauca, and play an important role in the ecological adaptation of dimorphic seeds by performing different biological function roles. The endophytic bacterial communities of the dimorphic seeds may be influenced mainly by the seed coat structureand partly by the seed phytochemical characteristics. These findings provide valuable information for better understanding of the ecological adaptation strategy of dimorphic seeds in the disturbed environment.
在棕褐色种子和黑色种子之间观察到种皮结构和植物化学特性的显着差异。总共9门,13班,31个订单,53个家庭,在双态种子中鉴定出102属。优势门是变形杆菌,Firmicutes,和放线菌.结果表明,种子二态化对内生细菌群落的多样性和丰富度影响不大,但棕色和黑色种子的细菌群落相对丰度差异显著。在门一级,放线菌倾向于在棕色种子中显著富集。在属一级,红球菌,Ralstonia,Pelomonas和缓生根瘤菌倾向于在棕色种子中显著富集,而Marinilactibacillus主要存在于黑色种子中。此外,棕色种子含有大量具有植物生长促进特性的细菌,而黑色种子呈现具有酶活性的细菌(即,果胶酶,纤维素分解和木聚糖分解活性)。
碱蓬双态种子的内生细菌群落组成差异显著,并通过发挥不同的生物学功能在二态种子的生态适应中发挥重要作用。双态种子的内生细菌群落可能主要受种皮结构的影响,部分受种子植物化学特性的影响。这些发现为更好地理解双态种子在受干扰环境中的生态适应策略提供了有价值的信息。