Nitrogen fixation by common beans in crop mixtures is influenced by growth rate of associated species

BMC Plant Biology

Research Article

Akanksha Singh¹  Christian Schöb²  Pietro P. M. Iannetta³ 

[1] Agricultural Ecology Group, Institute of Agricultural Sciences, ETH Zurich, Zurich, Switzerland;Department of International Cooperation, Research Institute of Organic Agriculture, Frick, Switzerland;Agricultural Ecology Group, Institute of Agricultural Sciences, ETH Zurich, Zurich, Switzerland;Área de Biodiversidad y Conservación, Universidad Rey Juan Carlos, 28933, Móstoles, Madrid, Spain;Department of Ecological Sciences, The James Hutton Institute, DD2 5DA, Dundee, Scotland, UK;

关键词: Biological nitrogen fixation;    Common bean;    Legumes;    Crop mixtures;    Plant nutrients;   

DOI  :  10.1186/s12870-023-04204-z

 received in 2022-10-26, accepted in 2023-03-29,  发布年份 2023

来源: Springer

【 摘 要 】

BackgroundLegumes can fix atmospheric nitrogen (N) and facilitate N availability to their companion plants in crop mixtures. However, biological nitrogen fixation (BNF) of legumes in intercrops varies largely with the identity of the legume species. The aim of our study was to understand whether BNF and concentration of plant nutrients by common bean is influenced by the identity of the companion plant species in crop mixtures. In this greenhouse pot study, common beans were cultivated with another legume (chickpea) and a cereal (Sorghum). We compared BNF, crop biomass and nutrient assimilation of all plant species grown in monocultures with plants grown in crop mixtures.ResultsWe found beans to exhibit low levels of BNF, and to potentially compete with other species for available soil N in crop mixtures. The BNF of chickpeas however, was enhanced when grown in mixtures. Furthermore, biomass, phosphorous and potassium values of chickpea and Sorghum plants were higher in monocultures, compared to in mixtures with beans; suggesting competitive effects of beans on these plants. Concentration of calcium, magnesium and zinc in beans was higher when grown with chickpeas than with Sorghum.ConclusionsIt is generally assumed that legumes benefit their companion plant species. Our study highlights the contrary and shows that the specific benefits of cereal-legume mixtures are dependent on the growth rate of the species concerned. We further highlight that the potential of legume-legume mixtures is currently undervalued and may play a strong role in increasing N use efficiency of intercrop-based systems.

【 授权许可】

CC BY   
© The Author(s) 2023

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