ABSTRACT

Maize-peanut intercropping (M//P) is widely used in the North China Plain, but little is known about the changes in soil microorganism and its interactions with soil nutrient availability. Based on 3 years of field experiment, this study systematically investigated the soil microorganisms and soil properties in the 0–10 cm, 10–20 cm and 20–40 cm soil layers. This study found that M//P changed the soil microbial community composition compared to monoculture modes in all the studied soil layers but had the most effects in the 10–20 cm soil layer. Soil organic carbon, available phosphorus and available potassium explained the most variation in the microbial composition, while Proteobacteria, Acidobacteria and Planctomycetes were the phyla that were most affected by environmental factors. Based on the correlations and microbial function analysis, we speculated that: 1) M//P increased the relative abundance of Chlorobi, Parcubacteria and Chlamydiae, which promoted carbon and nitrogen metabolism; 2) M//P increased the relative abundance of Chlamydiae, Saccharibacteria, and Parcubacteria and then enhanced phosphonate and phosphinate metabolism, providing more available phosphorus for crops; 3) some KEGG pathways related to immunity and disease were increased in M//P, which may be related to disease control.

摘要

玉米-花生间作（M//P）在华北平原广泛应用，但对土壤微生物的变化及其与土壤养分有效性的相互作用知之甚少。本研究基于3年的田间试验，系统地研究了0~10 cm、10~20 cm和20~40 cm土层的土壤微生物和土壤性质。本研究发现，在所有研究的土层中，与单一栽培模式相比，M//P 改变了土壤微生物群落组成，但在 10-20 cm 土层中的影响最大。土壤有机碳、速效磷和速效钾解释了微生物组成的最大变化，而变形菌、酸菌和浮游菌是受环境因素影响最大的门。基于相关性和微生物功能分析，我们推测：1）M//P增加了绿藻、Parcubacteria和衣原体的相对丰度，促进了碳和氮代谢；2）M // P增加的相对丰度衣原体，Saccharibacteria，和Parcubacteria然后增强的膦酸酯和次膦酸酯代谢，对于农作物提供更多的可用的磷; 3）M//P中一些与免疫和疾病相关的KEGG通路增加，可能与疾病控制有关。