Summary: This study investigates the potential of arbuscular mycorrhizal (AM) fungi to enhance the tolerance of two Cucurbitaceae species, cucumber (Cucumis sativus L.) and zucchini squash (Cucurbita pepo L.), to bicarbonate stress in irrigation water. The experiments were conducted in greenhouse conditions, comparing plants inoculated with AM fungi to those without (-AM). Nutrient solutions with varying pH levels (6.0 or 8.1) and bicarbonate concentrations (0 or 10 mM NaHCO3) were supplied to the plants.
Results showed that increasing bicarbonate concentration in the nutrient solution led to a significant decrease in yield, leaf area, net assimilation of CO2, and concentrations of N, P, K, and Fe in leaf tissue for both cucumber and zucchini. However, +AM plants exhibited higher marketable yield and fruit mean weight compared to -AM plants under alkaline conditions. Additionally, mycorrhizal plants had higher concentrations of macro- (P and K) and micro- (Fe) nutrients in leaf tissue than non-mycorrhizal plants under alkaline conditions.
The study suggests that the enhanced yield production in +AM plants is attributed to their ability to maintain higher net assimilation of CO2 and better nutritional status in response to bicarbonate stress compared to -AM plants. Overall, these findings highlight the potential of AM fungi to improve the tolerance of Cucurbitaceae species to alkaline conditions in irrigation water.
Publication: – Acta Horticulturae
