Department of Genetics, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan Rd, Lat Yao, Chatuchak, Bangkok, 10900, Thailand.
Omics Center for Agriculture, Bioresources, Food and Health, Kasetsart University (OmiKU), Bangkok, 10900, Thailand.
Folia Microbiol (Praha). 2022 Apr;67(2):329-337. doi: 10.1007/s12223-022-00948-7. Epub 2022 Jan 11.
Earthworms and their casts have been widely used for organic waste degradation and plant growth promotion. The microbial communities that reside in the guts and casts of earthworms markedly influence both applications. In the present study, next-generation sequencing was applied to identify the microbial communities in the guts and casts of three epigeic earthworm species, Eudrilus eugeniae, Perionyx excavatus, and Eisenia fetida, reared under two different feeding conditions. A total of 580 genera belonging to 43 phyla were identified. By comparing bacterial diversity among samples divided into groups based on the earthworm species, sample types, and conditions, the beta diversity analysis supported the impact of the sample type and suggested that there was significant dissimilarity of the bacterial diversity between the gut and cast. Besides, bacterial Phylum compositions within the group were compared. The result showed that the top three high relative frequency phyla found in the casts were the same regardless of earthworm species, while those found in the gut depended on both the condition and earthworm species. Focusing on the cellulolytic and plant growth-promoting bacteria, certain cellulolytic bacteria, Paenibacillus, Comamonas, and Cytophaga, were found only in the cast. Citrobacter and Streptomyces aculeolatus were detected only in the guts of earthworms reared in the bedding containing vegetables and bedding alone, respectively. Besides, Actinomadura and Burkholderia were detected only in the gut of E. eugeniae and E. fetida, respectively. The results proved that the microbial composition was affected by sample type, condition, and earthworm species. In addition, the proportion of these beneficial bacteria was also influenced by these factors. Hence, the information from this study can be used as a guide for selecting earthworm species or their casts for more efficient organic waste decomposition and plant growth promotion.
蚯蚓及其排泄物广泛应用于有机废物降解和植物生长促进。栖息在蚯蚓肠道和排泄物中的微生物群落显著影响这两个应用。在本研究中，应用下一代测序技术鉴定了在两种不同饲养条件下饲养的三种表栖蚯蚓（Eudrilus eugeniae、Perionyx excavatus 和 Eisenia fetida）的肠道和排泄物中的微生物群落。共鉴定出 580 个属，属于 43 个门。通过比较基于蚯蚓种类、样本类型和条件将样本分为组后的细菌多样性，β多样性分析支持样本类型的影响，并表明肠道和排泄物之间的细菌多样性存在显著差异。此外，还比较了组内细菌门组成。结果表明，无论蚯蚓种类如何，在排泄物中发现的前三个高相对频率的门都是相同的，而在肠道中发现的门则取决于条件和蚯蚓种类。关注纤维素分解菌和植物促生菌，某些纤维素分解菌（如 Paenibacillus、Comamonas 和 Cytophaga）仅在粪便中发现。Citrobacter 和 Streptomyces aculeolatus 仅在分别以蔬菜和单独垫料饲养的蚯蚓肠道中检测到。此外，Actinomadura 和 Burkholderia 仅在 E. eugeniae 和 E. fetida 的肠道中检测到。结果表明，微生物组成受样本类型、条件和蚯蚓种类的影响。此外，这些有益细菌的比例也受到这些因素的影响。因此，本研究的信息可用于指导选择蚯蚓种类或其排泄物，以更有效地进行有机废物分解和植物生长促进。
