College of Horticulture, Gansu Agricultural University, Lanzhou, China.
Vegetable Research Institute, Gansu Academy of Agricultural Sciences, Lanzhou, China.
PLoS One. 2023 Aug 11;18(8):e0289772. doi: 10.1371/journal.pone.0289772. eCollection 2023.
Cucumber is an important cash crop; however, continuous cropping obstacles readily occur within the intensive production processes of facility horticulture. This study aimed to determine the effects of continuous cropping on soil quality and the microbial community in the rhizosphere soil of cucumbers. Rhizosphere soil of cucumber planted continuously for 4, 8, and 12 years was investigated, and soil that was not continuously planted was used as the control. Soil physicochemical properties, enzyme activity, microbial diversity, and richness were determined. The results showed that with the increase in continuous cropping years (0, 4, 8, and 12 years), soil total salt content continuously increased, while the pH value significantly decreased. Compared with the control, soil organic matter, alkali-hydrolyzed nitrogen, available phosphorus, available potassium, and nitrate nitrogen contents increased significantly after 4 and 8 years of continuous cropping. Spearman correlation analysis showed that pH was negatively correlated with sucrase or sucrose and available phosphorus was positively correlated with alkaline phosphatase. Compared with the control, the diversity and abundance of bacterial and fungal communities in cucumber rhizosphere soil decreased after 4 and 12 years of continuous cropping. Continuous cropping led to a significant increase in the richness of the dominant phylum of cucumber rhizosphere soil. Principal coordinates analysis showed that, compared with the control, the soil microbial community structure was significantly separated after 4, 8, and 12 years of continuous cropping, and the microbial community structure was most similar after 4 and 8 years of continuous cropping. In addition, redundancy analysis showed that pH was the main driver of soil microbial dominance. In conclusion, continuous cropping of cucumber along the Yellow River irrigation area has led to the deterioration of soil nutrients and microbial communities in that region. This experiment provides a theoretical foundation for addressing the challenges associated with continuous cropping in cucumber cultivation.
黄瓜是一种重要的经济作物；然而，在设施园艺的集约化生产过程中，连续种植障碍很容易出现。本研究旨在确定连续种植对黄瓜根际土壤质量和微生物群落的影响。调查了连续种植 4、8 和 12 年的黄瓜根际土壤，未连续种植的土壤作为对照。测定了土壤理化性质、酶活性、微生物多样性和丰富度。结果表明，随着连续种植年限（0、4、8 和 12 年）的增加，土壤全盐含量持续增加，而 pH 值显著下降。与对照相比，连续种植 4 年和 8 年后，土壤有机质、碱解氮、有效磷、速效钾和硝态氮含量显著增加。Spearman 相关分析表明，pH 值与蔗糖酶或蔗糖呈负相关，有效磷与碱性磷酸酶呈正相关。与对照相比，黄瓜根际土壤细菌和真菌群落的多样性和丰度在连续种植 4 年和 12 年后均降低。连续种植导致黄瓜根际土壤优势门的丰富度显著增加。主坐标分析表明，与对照相比，连续种植 4、8 和 12 年后，土壤微生物群落结构明显分离，连续种植 4 年和 8 年后，土壤微生物群落结构最为相似。此外，冗余分析表明，pH 值是土壤微生物优势的主要驱动因素。总之，黄河灌区黄瓜连作导致了土壤养分和微生物群落的恶化。该实验为解决黄瓜连作栽培中面临的挑战提供了理论基础。
