鲁西南蒜–椒不同轮作年限土壤养分特征和微生物特性

Soil Nutrients and Microbial Characteristics of Garlic-Pepper in Different Continuous Rotation Years in Southwest Shandong Province

摘要: 以鲁西南地区蒜–椒不同轮作年限土壤为研究对象，对连作1年、3年、5年、7年等不同轮作年限的土壤养分特征、土壤微生物学特性、土壤酶活性、蒜–椒发病指数进行研究。结果表明：随着蒜–椒轮作年限的增加，蒜–椒产量逐年降低，且降低幅度逐渐增大；土壤pH值显著升高，土壤弱碱化进程加速；土壤有机质含量降低；土壤氮、磷、钾比例失调，碱解氮、有效磷和速效钾含量逐年升高，其中速效钾含量已呈偏高水平。同时，蒜–椒轮作年限也会对土壤微生物特征产生显著影响，具体表现为随着轮作年限的增加，细菌数量先低后高，真菌数量持续升高，B/F和A/F值逐年下降，土壤酶活性降低，大蒜根腐病和辣椒炭疽病等真菌性病害逐年加重。蒜–椒轮作至第5年出现明显重茬障碍，是改变单一蒜–椒轮作模式的最佳时期。

Abstract: In this paper, the soil of different continuous garlic/pepper rotation years in Southwest Shandong Province was studied with the treatments including continuous rotation for 1 year, 3years, 5years and 7 years. Soil nutrient characteristics, biological characteristics, enzyme activity, garlic and pepper disease indexes were studied. The results showed that the yield of garlic and pepper de-creased with the increasing of rotation planting years, and the lowered range increased year by year. The pH value and weak alkalization process significantly increased. Soil organic matter con-tent decreased; meanwhile, the content of available nitrogen, phosphorus and potassium increased year by year, and there was a proportional imbalance among nitrogen, phosphorus and potassium nutrients; especially the available potassium content was too high. The continuous rotation planting years of garlic/pepper also had significant effects on soil microbial characteristics. With the increasing of rotation planting years, the bacteria amount decreased first and increased afterwards; fungi amount continuously increased. Soil enzyme activity, B/F and A/F ratio all decreased; meanwhile, the fungi disease such as garlic root rot and pepper anthrax aggravated year by year. The replantation obstacles were significantly aggravated at the 5th year, which was the optimum period of changing the continuous garlic/pepper rotation planting pattern.