Atmospheric CO2 concentration affects the life cycle, yield, and fruit quality of early maturing edible legume cultivars

Abstract

Background: Elevated CO₂ usually reduces levels of proteins and essential micronutrients in crops. The adoption of early maturing varieties may minimize the deleterious effect of climate change on farming activities. Legumes stand out for their high nutritional quality, so the objective was to study whether the atmospheric CO₂ concentration affected the growth, yield, and food quality of early maturing cultivars of peas, snap beans, and faba beans. Plants grew in greenhouses either at ambient (ACO₂ , 392 μmol mol^-1 ) or under elevated (ECO₂ , 700 μmol mol^-1 ) CO₂ levels. Minerals, proteins, sugars, and phenolic compounds were measured in grains of peas and faba beans, and in pods of snap beans.

Results: The effect of ECO₂ depended on legume species, being more evident for food quality than for vegetative growth and yield. The ECO₂ increased Fe and P in faba bean grains, and Ca in snap bean pods. Under ECO₂ , grains of pea and faba bean increased levels of proteins and phenolics, respectively, and the sugars-to-protein ratio decreased in pods of snap beans.

Conclusion: Early maturing varieties of legumes appear to be an interesting tool to cope with the negative effects that a long exposure to rising CO₂ can exert on food quality. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Keywords: atmospheric CO2; faba bean; minerals; pea; proteins; snap bean.