Summary of Biostimulant – Water deficit improved the capacity of arbuscular mycorrhizal fungi (AMF) for inducing the accumulation of antioxidant compounds in lettuce leaves

How Biostimulant AMF Boost Antioxidants in Lettuce Under Water Stress

Biostimulant AMF boost antioxidants in lettuce, helping plants become more resilient to drought while producing leaves richer in health-promoting compounds. Lettuce, a major leafy vegetable in the European Union and a key product in the “Fourth Range” of ready-to-eat salads, benefits greatly from its association with arbuscular mycorrhizal fungi (AMF). This natural partnership shows promise for sustainable farming, combining improved crop performance with enhanced nutritional quality.

Growth Performance with AMF Biostimulant Under Limited Irrigation

Studies testing two popular cultivars—Batavia Rubia Munguía and Maravilla de Verano—under four irrigation regimes revealed important effects of AMF. Plants treated with the fungi maintained shoot biomass and relative water content even when watered at only two-thirds of field capacity. In fact, mycorrhizal lettuce under reduced irrigation often matched the performance of non-mycorrhizal plants grown with optimal watering. This shows that AMF help improve water-use efficiency without sacrificing yields.

Antioxidant Boost from Biostimulant AMF

Along with supporting growth, biostimulant AMF boost antioxidants, leading to greater accumulation of carotenoids and anthocyanins, with smaller but meaningful increases in chlorophylls and phenolics. These bioactive compounds are associated with human health benefits such as reducing oxidative stress and supporting cellular protection. Interestingly, the antioxidant enrichment was most pronounced under water deficit, showing that reduced irrigation combined with AMF can make lettuce even more nutritious.

Toward Sustainable Salad Production with Mycorrhizal Support

By improving plant tolerance to drought and enriching the nutritional profile of leaves, AMF biostimulants offer a sustainable strategy for lettuce production. Farmers can save water while maintaining yields, and consumers benefit from healthier vegetables. This natural solution provides a pathway toward climate-smart agriculture, ensuring both productivity and quality in lettuce farming.