Xiao Wanting, Zhang Zhanling, Wang Hai, Han Guiqi, Yan Zhu-Yun, He Dongmei
Key Laboratory of Characteristic Chinese Medicinal Resources in Southwest, Chengdu, Sichuan, China.
School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China.
PeerJ. 2023 Jul 26;11:e15579. doi: 10.7717/peerj.15579. eCollection 2023.
Long-term asexual reproduction can easily lead to the degradation of plant germplasm, serious diseases and insect pests, reduction of production and even catastrophic crop failure. "Mountain Breeding and Dam Cultivation" is the main cultivation mode of Hort., which successfully avoided the germplasm degradation caused by long-term asexual reproduction. The recombination of endophytic fungi of caused by off-site transplantation was considered to be an important reason for its germplasm rejuvenation. However, whether bacteria have the same regularity is not yet known.
In this study, we carried out the experiment of cultivating propagation materials of in different regions and transplanting them to the same region. High-throughput sequencing was performed to analyze the bacterial communities in and its soil.
The results showed that after transplanting, the plant height, tiller number, fresh weight, . of in mountainous areas were significantly higher than those in dam areas. At the same time, significant changes had taken place in the endophytic bacteria in reproductive material stem nodes (Lingzi, abbreviated as LZ). The diversity and abundance of bacteria in dam area LZ (YL) are significantly higher than those in mountainous area LZ (ML). The relative abundance of bacteria such as Xanthobacteraceae, Micromonosporaceae, Beijerinkiaceae, Rhodanobacteria, in ML is significantly higher than YL, mainly classified in Proteobateria and Actinobacteriota. In addition, the abundance advantage of Actinobacteriota still exists in MY (underground mature rhizomes obtained by ML). Meanwhile, the bacterial community was different in different area of transplanting. The diversity of bacterial communities in dam soil (YLS) is significantly higher than that in mountain soil (MLS). MLS had more Acidobacteriota than YLS. Comparative analysis showed that 74.38% of bacteria in ML are found in MLS, and 87.91% of bacteria in YL are found in YLS.
We can conclude that the community structure of endophytic bacteria recombined after the transplantation of , which was related to the bacterial community in soils. Moreover, after transplanting in mountainous areas, LZ accumulated more potentially beneficial Actinobacteriota, which may be an important reason for promoting the rejuvenation of germplasm in . However, this hypothesis requires more specific experiments to verify. This study provided a new idea that off-site transplanting may be a new strategy to restore vegetative plant germplasm resources.
长期无性繁殖容易导致植物种质退化、病虫害严重、产量降低甚至作物灾难性歉收。“山地育种与坝区栽培”是某园艺作物的主要栽培模式，该模式成功避免了长期无性繁殖导致的种质退化。异地移栽引起的该作物内生真菌重组被认为是其种质复壮的重要原因。然而，细菌是否具有相同规律尚不清楚。
在本研究中，我们进行了在不同区域培育该作物繁殖材料并将其移栽到同一区域的试验。采用高通量测序分析该作物及其土壤中的细菌群落。
结果表明，移栽后，山区该作物的株高、分蘖数、鲜重等均显著高于坝区。同时，繁殖材料茎节（令仔，简称LZ）中的内生细菌发生了显著变化。坝区LZ（YL）中细菌的多样性和丰度显著高于山区LZ（ML）。ML中黄杆菌科、小单孢菌科、拜叶林克氏菌科、红杆菌科等细菌的相对丰度显著高于YL，主要分类于变形菌门和放线菌门。此外，放线菌门在MY（由ML获得的地下成熟根茎）中的丰度优势仍然存在。同时，移栽不同区域的细菌群落不同。坝区土壤（YLS）中细菌群落的多样性显著高于山区土壤（MLS）。MLS中的酸杆菌门比YLS多。比较分析表明，ML中74.38%的细菌存在于MLS中，YL中87.91%的细菌存在于YLS中。
我们可以得出结论，该作物移栽后内生细菌群落结构发生重组，这与土壤中的细菌群落有关。此外，在山区移栽后，LZ积累了更多潜在有益的放线菌门，这可能是促进该作物种质复壮的重要原因。然而，这一假设需要更多具体实验来验证。本研究提供了一个新思路，即异地移栽可能是恢复无性繁殖植物种质资源的新策略。
