Tao Liang, Zhang Chunsheng, Ying Zhiping, Xiong Zhi, Vaisman Haim Shalom, Wang Changming, Shi Zhuogong, Shi Rui
Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Landscape Architecture Engineering Research Center of National Forestry and Grassland Administration, Southwest Forestry University, Kunming, Yunnan, China.
Office of Academic Affairs, Yunnan University of Finance and Economics, Kunming, Yunnan, China.
Front Microbiol. 2022 Oct 6;13:952092. doi: 10.3389/fmicb.2022.952092. eCollection 2022.
is the most economically important Proteaceae crop known for its edible nuts. The present study was conducted to examine the effect of continuous cultivation (for 1, 5, and 20 years) of on soil quality, bacterial diversity, and metabolites. Soil rhizospheres from three different rhizosphere orchards, 1-year monoculture orchard (CK), 5-year monoculture orchard (Y5), and 20-year monoculture orchard (Y20), were analyzed through metagenomic and metabolomic profiling. The soil physicochemical properties, including organic matter, and available nutrients (P, N, and K) were first increased significantly ( < 0.05) from the CK to the Y5 group and then decreased ( < 0.05) from the Y5 to the Y20 group. The soil pH continuously decreased ( < 0.05) over time from CK to Y20. Metagenomic profiling revealed that Actinobacteria, Acidobacteria, and Proteobacteria were the top three abundant phyla with their inconsistent relative abundance patterns from CK to Y20 (CK: 23.76%, Y5: 34. 06%, and Y20: 31.55%), (CK: 13.59%, Y5: 18.59%, and Y20: 21.35%), and (CK: 27.59%, Y5: 15.98%, and Y20: 17.08%), respectively. Furthermore, the Y5 rhizospheres had a higher number of beneficial bacterial genera belonging to Proteobacteria and Actinobacteria than the Y20 rhizospheres. The KEGG annotation analysis revealed that cellular processes, organism systems, metabolism, and genetic information were the most enriched functional categories. CAZy database screening indicated the highest enrichment of glycoside hydrolases following the glycoside transferases and carbohydrate-binding modules. Differential metabolite analysis revealed the highest number of metabolites (11) in the Y5 group than in the Y20 group (6). It is concluded that continuous monoculture of improves the soil physicochemical properties, bacterial diversity, and metabolite contents in short-term planted orchards which, however, are deteriorated in long-term planted orchards.
是最具经济重要性的山龙眼科作物，以其可食用坚果而闻名。本研究旨在考察连续种植（1年、5年和20年）对土壤质量、细菌多样性和代谢产物的影响。通过宏基因组学和代谢组学分析，对来自三个不同的根际果园的土壤根际进行了分析，这三个果园分别是1年单作果园（CK）、5年单作果园（Y5）和20年单作果园（Y20）。土壤理化性质，包括有机质和有效养分（磷、氮和钾），首先从CK组到Y5组显著增加（P<0.05），然后从Y5组到Y20组下降（P<0.05）。土壤pH值从CK到Y20随时间持续下降（P<0.05）。宏基因组分析表明，放线菌门、酸杆菌门和变形菌门是丰度最高的三个门类，它们从CK到Y20的相对丰度模式不一致（CK：23.76%，Y5：34.06%，Y20：31.55%），（CK：13.59%，Y5：18.59%，Y20：21.35%），以及（CK：27.59%，Y5：15.98%，Y20：17.08%）。此外，Y5根际中属于变形菌门和放线菌门的有益细菌属数量比Y20根际更多。KEGG注释分析表明，细胞过程、生物系统、代谢和遗传信息是最丰富的功能类别。CAZy数据库筛选表明，糖苷水解酶在糖苷转移酶和碳水化合物结合模块之后富集程度最高。差异代谢物分析显示，Y5组中的代谢物数量（11种）比Y20组（6种）最多。得出的结论是，连续单作对短期种植果园的土壤理化性质、细菌多样性和代谢物含量有改善作用，但在长期种植果园中会恶化。
