The power of sister crops: intercropping courgette and common bean changes floral morphology and increases diversity of flower visitors

ABSTRACT

Acknowledging species interactions is essential for managing diversity in complex agricultural systems. To understand the neighbouring plant effect on flower number and size, we performed a greenhouse experiment with paired pots in three treatments: focal plant (common bean/courgette) with conspecific neighbour, heterospecific neighbour or empty pot. Common beans without neighbours produced more flowers than when accompanied. Common bean with conspecific neighbours produced more flowers than with heterospecific neighbours, with larger standard petals. Courgettes with heterospecific neighbours had flowers with deeper corollas than with conspecific neighbours. To understand effects on visitation and production, we performed a field experiment comparing courgette monoculture, common bean monoculture and three intercroppings, varying the crop ratio. Species composition of floral visitors differed significantly between monoculture and intercropping. The six plots (6/21) with highest diversity were intercropping. Intercropping courgette and common bean can change floral morphology and alter plant–pollinator interactions in the agroecosystem, enhancing pollinator diversity.

Key policy insights

• this article provides an empirical basis for the adoption of multispecies consortia in agroecosystems as an instrument to foster local pollinator biodiversity;

• it provides empirical evidence that neighbouring plant species identity can have an effect on flowers’ morphological traits, which may be an important consideration when planning and managing agroecosystems;

• it reinforces that diversified crop systems, with known ecological advantages, can be grown without production loss;

• it supports that scientific development towards more sustainable food systems should include traditional knowledge systems.

GRAPHICAL ABSTRACT

KEYWORDS:

• Consortium
• Cucurbita pepo
• Phaseolus vulgaris
• plant–plant interactions
• plant–pollinator interactions
• crop pollination

Acknowledgements

We thank Ilio Montanari Jr. for providing access to the experimental areas at the CPQBA and Marcelo Kubo for the illustrations used in the graphical abstract.

Author contributors

GR, CEPN and MP conceived the hypotheses and the experimental design to test them. GR installed and performed the greenhouse experiments. GR and CEPN installed and performed the field experiment. GR collected all data from both experiments. GR wrote a first draft of the manuscript, which was then revised by the three authors until all agreed on a final version

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/14888386.2023.2179112

Additional information

Funding

This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001 and by the Conselho Nacional de Desenvolvimento Científico e Tecnológico – Brasil (CNPq), grant 132220/2017-2. MP received support from FAEPEX-UNICAMP (grant no. 60412 and PAPDIC-CNPq 2014/4715.

Notes on contributors

Gabriela Rabeschini

Gabriela Rabeschini has a BSc in biological sciences and an MSc in ecology from the University of Campinas (Unicamp). She performed this work as part of her MSc studies.

Carlos E. P. Nunes

Carlos E. P. Nunes has a PhD in plant biology and has built his academic career mostly doing research in pollination ecology.

Martin Pareja

Martin Pareja is an assistant professor of animal ecology at Unicamp. His research focusses on plant–insect interactions and plant-mediated indirect effects.