Maize/peanut intercropping improves nutrient uptake of side-row maize and system microbial community diversity

Xinhua Zhao,Yi Han,Xiaolong Shi,Chunji Jiang,Qiqi Dong,Xibo Liu,Yang Yuan,Haiqiu Yu,Dongying Zhou,Xiaoguang Wang,Kai Wang,Kezhao Zhang,Xu Yang,He Zhang,Zhimeng Zhang

doi:10.1186/s12866-021-02425-6

Abstract

BackgroundIntercropping, a diversified planting pattern, increases land use efficiency and farmland ecological diversity. We explored the changes in soil physicochemical properties, nutrient uptake and utilization, and microbial community composition in wide-strip intercropping of maize and peanut.ResultsThe results from three treatments, sole maize, sole peanut and intercropping of maize and peanut, showed that intercropped maize had a marginal advantage and that the nutrient content of roots, stems and grains in side-row maize was better than that in the middle row of intercropped maize and sole maize. The yield of intercropped maize was higher than that of sole cropping. The interaction between crops significantly increased soil peroxidase activity, and significantly decreased protease and dehydrogenase activities in intercropped maize and intercropped peanut. The diversity and richness of bacteria and fungi decreased in intercropped maize rhizosphere soil, whereas the richness of fungi increased intercropped peanut. RB41, Candidatus-udaeobacter, Stropharia, Fusarium and Penicillium were positively correlated with soil peroxidase activity, and negatively correlated with soil protease and dehydrogenase activities. In addition, intercropping enriched the functional diversity of the bacterial community and reduced pathogenic fungi.ConclusionIntercropping changed the composition and diversity of the bacterial and fungal communities in rhizosphere soil, enriched beneficial microbes, increased the nitrogen content of intercropped maize and provided a scientific basis for promoting intercropping in northeastern China.

Highlights

Intercropping, a diversified planting pattern, increases land use efficiency and farmland ecological diversity
The maize grain nitrogen uptake was increased by 25.5% in strip intercropping of maize and soybean in southwestern of China [11]
Legumes have a symbiotic relationship with nitrogen-fixing bacteria and through increased abundance of the nitrogen-fixing gene nifH, leguminous crops are able to obtain nitrogen from the air; intercropping with legumes allows neighbouring crops to absorb more nitrogen from the soil [14,15,16]

Summary

Introduction

Intercropping, a diversified planting pattern, increases land use efficiency and farmland ecological diversity. We explored the changes in soil physicochemical properties, nutrient uptake and utilization, and microbial community composition in wide-strip intercropping of maize and peanut. Previous studies have shown that crop nutrient uptake was affected by soil nutrient distribution and neighbouring crops in an intercropping system [9]. The intercropping of proso millet and mung bean has increased the nitrogen absorption efficiency by 96 and 71.6%, respectively, on the Loess Plateau of China, due to the complementarity of crops [10]. The maize grain nitrogen uptake was increased by 25.5% in strip intercropping of maize and soybean in southwestern of China [11]. By changing the spatial distribution of roots, delaying root senescence and increasing root activity to achieve niche complementation, the nitrogen uptake and utilization of maize can be improved [12, 13]. Studies have shown that maize root exudates promote the expression of chalconeflavanone isomerase and the synthesis of flavonoids in bean roots, increasing nodulation and nitrogen fixation [17,18,19]

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Results

Discussion

Conclusion