Mitigating drought effects in maize with Trichoderma harzianum (strain - ESALQ 1306): a bioinoculant for sustainable agriculture

Agriculture faces increasing challenges due to climate change, underscoring the importance of beneficial microorganisms for enhancing crop resilience and improving soil health. However, the performance of microbial inoculant strains can vary widely depending on the cultivated species and environmental conditions. This study evaluated the ESALQ 1306 strain of Trichoderma harzianum, a soil fungus recognised as a biological control agent for crops such as soybean and strawberry, investigating its potential as a growth promoter in maize (Zea mays L.). Field experiments were conducted with three commercial cultivars (DKB255, DKB360, and 2B810) over two growing seasons, one under irrigation and the other under severe natural drought. The results revealed that Trichoderma (ESALQ 1306) significantly increased plant height, biomass, and grain yield, particularly under drought stress, despite lacking a formal recommendation for maize. The cv. DKB360 showed the greatest response, with yield increases of up to 60% compared to untreated controls. Inoculation also improved nutrient uptake, especially nitrogen, highlighting its potential to maintain soil health and fertility. These findings demonstrate that the ESALQ 1306 strain of Trichoderma is a promising soil bioinoculant for agriculture, capable of improving maize performance under both optimal and stressful conditions. However, it is important to emphasise that genotype-specific responses highlight the need to align bioinoculant application with selecting specific cultivars to ensure inoculation success. This insight is crucial for guiding future breeding programs and establishing clear regulatory guidelines for commercialising biological products, fostering sustainable and resilient agricultural systems.