Summary of ARBUSCULAR MYCORRHIZAL FUNGI ENHANCE TOLERANCE OF TWO CUCURBITACEAE SPECIES TO BICARBONATE IN IRRIGATION WATER
Mycorrhiza Boosts Cucurbit Bicarbonate Tolerance: Enhancing Yield and Nutrient Uptake
Arbuscular mycorrhizal (AM) fungi play a crucial role in improving plant tolerance to alkaline soil conditions. This study investigated whether mycorrhiza boosts cucurbit bicarbonate tolerance in two important Cucurbitaceae species: cucumber (Cucumis sativus L.) and zucchini squash (Cucurbita pepo L.). Two greenhouse experiments were conducted, comparing AM-inoculated (+AM) and non-inoculated (-AM) plants under nutrient solutions with normal (pH 6.0) and high pH (pH 8.1) levels. The high pH solutions contained additional NaHCO3 (10 mM) and CaCO3 (0.5 g L-1) to simulate alkaline stress.
Effects of Bicarbonate Stress on Cucurbit Growth
Increasing NaHCO3 concentrations significantly reduced yield, leaf area, net CO2 assimilation (ACO2), and nutrient concentrations (N, P, K, and Fe) in leaves of both cucumber and zucchini. These reductions were more pronounced in non-mycorrhizal plants, highlighting the challenges of alkaline soil conditions on crop performance.
Role of Mycorrhiza in Alkaline Tolerance
Mycorrhiza boosts cucurbit bicarbonate tolerance by enhancing nutrient uptake and photosynthetic efficiency. In +AM plants, marketable yield and average fruit weight were significantly higher under high pH conditions compared to -AM plants. Leaf tissue analysis showed improved concentrations of key macro- (P, K) and micro-nutrients (Fe), indicating better nutritional status and stress resilience.
Implications for Sustainable Cucurbit Cultivation
The results suggest that AM inoculation can be a practical strategy to mitigate bicarbonate-induced stress in cucurbit crops. By maintaining higher net CO2 assimilation and optimal nutrient balance, mycorrhizal cucumber and zucchini plants can achieve superior yield and fruit quality in alkaline soils. Implementing AM fungi in greenhouse and field conditions could therefore enhance productivity and nutritional efficiency in challenging environments.
Conclusion: Leveraging mycorrhizal symbiosis offers a promising solution for improving cucurbit growth and yield under bicarbonate stress, confirming that mycorrhiza boosts cucurbit bicarbonate tolerance in both cucumber and zucchini.
Publication: – Acta Horticulturae
