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Aims: The objective of this study was to propose a maize–peanut intercropping system for traditional sole maize to increase economic benefits and decrease environmental pollution for dryland farming. Methods: The treatments comprised sole maize, sole peanut, maize–peanut intercropping, maize–peanut intercropping–rotation (rotation of the maize and peanut planting strips every year), and maize–peanut intercropping–rotation with 20% and 40% N reduction in maize planting strip. Soil water and total N stock, photosynthetic traits, yield, greenhouse gas emissions, economic income, and interspecific relationships were evaluated. Results: Intercropped maize absorbed more moisture but lost more N than sole maize. Maize–peanut intercropping had higher economic benefits and less N2O emissions than sole maize, but had no intercropped advantage on land equivalent ratio. In addition, intercropping increased the continuous cropping barriers of peanuts than a sole peanut. Rotation of the planting strips in intercropping increased the peanut yield and economic benefits compared with not rotating the planting strips, and the economic benefits reached the highest level in the third planting year. A 20% N reduction in maize planting strips can decrease the global warming potential without affecting economic benefits. A 40% N reduction in maize planting strips could reduce soil N stock, maize yield, water use efficiency, N use efficiency, land equivalent ratio, and income. Conclusions: A maize–peanut intercropping–rotation system is recommended for dryland farming since it promoted efficient use of N and economic benefits and decreased N2O emission. The proper N reduction in maize planting does not lead to N stress but decreased global warming potential. [ABSTRACT FROM AUTHOR]

Background and Aims: In communities, plants often simultaneously interact with intra- and inter-specific neighbours and heterogeneous nutrients. How plants respond under these conditions and then affect the structure and function of communities remain important questions. Methods: Maize ( Zea mays L.) was intercropped with potatoes ( Solanum tuberosum L.). In the field experiment, we applied fertilizer both homogeneously and heterogeneously under monocropping and intercropping conditions. The heterogeneous nutrient treatment in intercropping was designed with different fertilizer placements, at intraspecific and interspecific rows, respectively. In the pot experiment, crops were grown under both homogeneous and heterogeneous nitrogen conditions with single plant, intraspecific and interspecific competition. Shoot and root biomass and yield were measured to analyse crop performance. Results: In the field experiment, the heterogeneous nitrogen, compared with the homogenous one, enhanced the performance of the intercropped crop. Importantly, this effect of heterogeneous nitrogen was greater when fertilizer was applied at interspecific rows, rather than at intraspecific rows. Moreover, in pot experiments, the root foraging precision of the two crops was increased by interspecific neighbours, but only that of potatoes was increased by intraspecific neighbours. Conclusions: The integrated responses of plants to heterogeneous neighbours and nutrients depend on the position of nutrient-rich patches, which deepen our understanding of the function of plant diversity, and show that fertilizer placement within multi-cropping systems merits more attention. Moreover, the enhanced utilization of heterogeneous nitrogen could drive overyielding in multi-cropping systems. [ABSTRACT FROM AUTHOR]

In a previous paper [Bedoussac L, Justes E () Plant Soil, doi: ], we showed that intercropping of durum wheat and winter pea increased the yield and protein concentration of durum wheat when early N availability was less than 120 kg N ha−1. The aim of the present work was to understand these results by analysing intercrop species dynamics for growth, light and N acquisition. A 2-year field experiment was carried out in southwest France with different fertilizer-N levels in order to compare wheat ( Triticum turgidum L.) and pea ( Pisum sativum L.) grown as sole crops and as an intercrop in a row substitutive design. The advantages of intercropping in low N conditions were due mainly to: (1) better light use (up to 10%), thanks to species dynamic complementarity for leaf area index and height; (2) growth complementarity over time (higher growth rate of wheat until pea flowering and then of pea until wheat flowering); and (3) dynamic complementary N acquisition associated with better wheat N status throughout growth. Disadvantages, underlining poorer complementarity within the intercrop stand, were observed with ample available N in early growth. This induced higher cereal growth during winter, which led to increase interspecies competition by reducing pea light absorption and, consequently, its biomass production. [ABSTRACT FROM AUTHOR]