Qingshan Li, Yu Zhu, Zhiyu Liao, Yan Yin, Liyuan Liao, Xinni Li, Jinyan Huang, Guifen Li, Yi He, Zhiyang Wei, Shangdong Yang
{"title":"Variations in rhizosphere microbial community structure and function among diploid, triploid, and tetraploid watermelon cultivars","authors":"Qingshan Li, Yu Zhu, Zhiyu Liao, Yan Yin, Liyuan Liao, Xinni Li, Jinyan Huang, Guifen Li, Yi He, Zhiyang Wei, Shangdong Yang","doi":"10.1186/s40538-026-01026-7","DOIUrl":null,"url":null,"abstract":"<div><h3>Purpose</h3><p>The rhizosphere microbiome, as the “second genome” of plants, plays a crucial role in nutrient acquisition, stress resistance, and soil health maintenance. Polyploidization is a key breeding strategy for watermelon: triploids are valued for seedlessness and high stress resistance, while tetraploids serve as important parental materials for triploid hybridization. However, how ploidy level (diploid, triploid, tetraploid) shapes the micro-ecological environment and microbial community assembly remains unclear. This study aims to investigate the associations between ploidy level and rhizosphere microbiota composition in watermelon.</p><h3>Methods</h3><p>High-throughput sequencing (Illumina MiSeq PE300 for bacteria, PE250 for fungi) targeting the bacterial 16S rRNA gene and fungal ITS region was used to analyze rhizosphere microbial communities of diploid (HLL40-3), triploid (Guixi No.5), and tetraploid (MT410n-1) watermelons. α diversity, β diversity, taxonomic composition and functional prediction were performed to compare differences among groups.</p><h3>Results</h3><p>The Shannon index and richness indices (Ace and Chao1) of bacteria in the triploid were significantly higher than those in the diploid and tetraploid. Regarding fungi, only the richness in the triploid was significantly higher than that in the diploid and tetraploid. There was no significant difference in the fungal Shannon index between the triploid and diploid, and both were significantly higher than that of the tetraploid. β diversity analysis confirmed distinct separation of microbial communities across ploidy levels (<i>p</i> < 0.05). Taxonomically, diploid rhizospheres were enriched in <i>Proteobacteria</i>, <i>Melanconiella</i>, and <i>Hypomyces</i>; triploids were enriched in <i>Bacteroidota</i>, <i>Microvirga</i>, <i>Mortierellomycota</i>, <i>Cercophora</i>, and <i>Neocosmospora</i>; tetraploids were specifically enriched in <i>Patescibacteria</i>, <i>Gaiella</i>, <i>Trichoderma</i>, and <i>Papiliotrema</i>. Functional prediction showed diploids were dominated by plant/wood saprotrophs; triploids harbored diverse functional guilds (animal pathogens, endophytes, soil saprotrophs, etc.); tetraploids had the highest relative abundance of undefined saprotrophs.</p><h3>Conclusions</h3><p>Triploid watermelons establish a more diverse microbial community via selective recruitment, which might contribute to their superior agronomic characteristics.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":512,"journal":{"name":"Chemical and Biological Technologies in Agriculture","volume":"13 1","pages":""},"PeriodicalIF":5.8000,"publicationDate":"2026-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1186/s40538-026-01026-7.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemical and Biological Technologies in Agriculture","FirstCategoryId":"97","ListUrlMain":"https://link.springer.com/article/10.1186/s40538-026-01026-7","RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"AGRICULTURE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Purpose
The rhizosphere microbiome, as the “second genome” of plants, plays a crucial role in nutrient acquisition, stress resistance, and soil health maintenance. Polyploidization is a key breeding strategy for watermelon: triploids are valued for seedlessness and high stress resistance, while tetraploids serve as important parental materials for triploid hybridization. However, how ploidy level (diploid, triploid, tetraploid) shapes the micro-ecological environment and microbial community assembly remains unclear. This study aims to investigate the associations between ploidy level and rhizosphere microbiota composition in watermelon.
Methods
High-throughput sequencing (Illumina MiSeq PE300 for bacteria, PE250 for fungi) targeting the bacterial 16S rRNA gene and fungal ITS region was used to analyze rhizosphere microbial communities of diploid (HLL40-3), triploid (Guixi No.5), and tetraploid (MT410n-1) watermelons. α diversity, β diversity, taxonomic composition and functional prediction were performed to compare differences among groups.
Results
The Shannon index and richness indices (Ace and Chao1) of bacteria in the triploid were significantly higher than those in the diploid and tetraploid. Regarding fungi, only the richness in the triploid was significantly higher than that in the diploid and tetraploid. There was no significant difference in the fungal Shannon index between the triploid and diploid, and both were significantly higher than that of the tetraploid. β diversity analysis confirmed distinct separation of microbial communities across ploidy levels (p < 0.05). Taxonomically, diploid rhizospheres were enriched in Proteobacteria, Melanconiella, and Hypomyces; triploids were enriched in Bacteroidota, Microvirga, Mortierellomycota, Cercophora, and Neocosmospora; tetraploids were specifically enriched in Patescibacteria, Gaiella, Trichoderma, and Papiliotrema. Functional prediction showed diploids were dominated by plant/wood saprotrophs; triploids harbored diverse functional guilds (animal pathogens, endophytes, soil saprotrophs, etc.); tetraploids had the highest relative abundance of undefined saprotrophs.
Conclusions
Triploid watermelons establish a more diverse microbial community via selective recruitment, which might contribute to their superior agronomic characteristics.
期刊介绍：
Chemical and Biological Technologies in Agriculture is an international, interdisciplinary, peer-reviewed forum for the advancement and application to all fields of agriculture of modern chemical, biochemical and molecular technologies. The scope of this journal includes chemical and biochemical processes aimed to increase sustainable agricultural and food production, the evaluation of quality and origin of raw primary products and their transformation into foods and chemicals, as well as environmental monitoring and remediation. Of special interest are the effects of chemical and biochemical technologies, also at the nano and supramolecular scale, on the relationships between soil, plants, microorganisms and their environment, with the help of modern bioinformatics. Another special focus is the use of modern bioorganic and biological chemistry to develop new technologies for plant nutrition and bio-stimulation, advancement of biorefineries from biomasses, safe and traceable food products, carbon storage in soil and plants and restoration of contaminated soils to agriculture.
This journal presents the first opportunity to bring together researchers from a wide number of disciplines within the agricultural chemical and biological sciences, from both industry and academia. The principle aim of Chemical and Biological Technologies in Agriculture is to allow the exchange of the most advanced chemical and biochemical knowledge to develop technologies which address one of the most pressing challenges of our times - sustaining a growing world population.
Chemical and Biological Technologies in Agriculture publishes original research articles, short letters and invited reviews. Articles from scientists in industry, academia as well as private research institutes, non-governmental and environmental organizations are encouraged.
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
