Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
Environ Sci Pollut Res Int. 2021 Sep;28(35):48080-48096. doi: 10.1007/s11356-021-14033-y. Epub 2021 Apr 26.
Sugarcane monoculture (SM) often leads to soil problems, like soil acidification, degradation, and soil-borne diseases, which ultimately pose a negative impact on agricultural productivity and sustainability. Understanding the change in microbial communities' composition, activities, and functional microbial taxa associated with the plant and soil under SM is unclear. Using multidisciplinary approaches such as Illumina sequencing, measurements of soil properties, and enzyme activities, we analyzed soil samples from three sugarcane fields with different monoculture histories (1-, 2-, and 4-year cultivation times, respectively). We observed that SM induced soil acidity and had adverse effects on soil fertility, i.e., soil organic matter (OM), total nitrogen (TN), total carbon (TC), and available potassium (AK), as well as enzyme activities indicative for carbon, phosphorus, and nitrogen cycles. Non-metric multidimensional scaling (NMDS) analysis showed that SM time greatly affected soil attribute patterns. We observed strong correlation among soil enzymes activities and soil physiochemical properties (soil pH, OM, and TC). Alpha diversity analysis showed a varying response of the microbes to SM time. Bacterial diversity increased with increasing oligotrophs (e.g., Acidobacteria and Chloroflexi), while fungal diversity decreased with reducing copiotrophs (e.g., Ascomycota). β-Diversity analysis showed that SM time had a great influence on soil microbial structure and soil properties, which led to the changes in major components of microbial structure (soil pH, OM, TC, bacteria and soil pH; TC, fungi). Additionally, SM time significantly stimulated (four bacterial and ten fungal) and depleted (12 bacterial and three fungal) agriculturally and ecologically important microbial genera that were strongly and considerably correlated with soil characteristics (soil pH, OM, TC, and AK). In conclusion, SM induces soil acidity, reduces soil fertility, shifts microbial structure, and reduces its activity. Furthermore, most beneficial bacterial genera decreased significantly due to SM, while beneficial fungal genera showed a reverse trend. Therefore, mitigating soil acidity, improving soil fertility, and soil enzymatic activities, including improved microbial structure with beneficial service to plants and soil, can be an effective measure to develop a sustainable sugarcane cropping system.
甘蔗连作（SM）通常会导致土壤问题，如土壤酸化、退化和土传病害，这最终会对农业生产力和可持续性产生负面影响。目前尚不清楚与 SM 下植物和土壤相关的微生物群落组成、活性和功能微生物类群的变化。本研究采用 Illumina 测序、土壤性质测量和酶活性等多学科方法，分析了三个具有不同连作历史（分别为 1、2 和 4 年种植时间）的甘蔗田的土壤样本。我们观察到 SM 导致土壤酸化，并对土壤肥力产生不利影响，例如土壤有机质（OM）、总氮（TN）、总碳（TC）和有效钾（AK）以及指示碳、磷和氮循环的酶活性。非度量多维尺度分析（NMDS）表明 SM 时间极大地影响了土壤属性模式。我们观察到土壤酶活性与土壤理化性质（土壤 pH、OM 和 TC）之间存在强烈的相关性。α多样性分析表明微生物对 SM 时间的反应不同。细菌多样性随着寡营养菌（如酸杆菌门和绿弯菌门）的增加而增加，而真菌多样性随着富营养菌（如子囊菌门）的减少而减少。β多样性分析表明 SM 时间对土壤微生物结构和土壤性质有很大影响，这导致了微生物结构的主要成分（土壤 pH、OM、TC、细菌和土壤 pH；TC、真菌）发生变化。此外，SM 时间显著刺激（4 种细菌和 10 种真菌）和消耗（12 种细菌和 3 种真菌）对农业和生态重要的微生物属，这些微生物属与土壤特性（土壤 pH、OM、TC 和 AK）密切相关。总之，SM 会导致土壤酸化、降低土壤肥力、改变微生物结构并降低其活性。此外，由于 SM，大多数有益的细菌属显著减少，而有益的真菌属则呈现相反的趋势。因此，缓解土壤酸化、提高土壤肥力和土壤酶活性，包括改善对植物和土壤有益的微生物结构，可以是开发可持续甘蔗种植系统的有效措施。
