Influência da cobertura do solo na produtividade de cultivares de alface em condições de altas temperaturas no Amapá

Abstract

Lettuce (Lactuca sativa L.) is a widely cultivated vegetable; however, it is sensitive to high-temperature conditions, which are common during the summer in the state of Amapá and may compromise its development. This study aimed to evaluate the influence of soil cover with grass on the development of lettuce cultivars grown under high-temperature conditions. The experiment was conducted in the municipality of Porto Grande, in the state of Amapá, during the summer period, using a randomized block experimental design with a factorial arrangement composed of lettuce cultivars and two soil management conditions (with and without plant cover). Soil cover was applied through the distribution of Mombasa grass on the surface of the beds. Evaluations focused on variables related to plant growth and development, including shoot biomass accumulation, plant morphological conformation, and root system responses. The results demonstrated that the presence of plant cover provided more favorable conditions for lettuce development, resulting in greater shoot biomass production and improved plant conformation when compared to cultivation in uncovered soil. Root system responses were less expressive, a behavior consistent with the characteristics of the crop, without compromising overall plant performance. Differences among the evaluated cultivars highlighted the influence of genetic characteristics on adaptation to the environment modified by soil cover. The use of plant cover contributed to the modification of soil conditions during the experimental period, promoting a more stable environment for plant growth under elevated temperatures. These effects reinforce the relevance of soil management as a strategy to mitigate the impacts of thermal stress in lettuce cultivation systems. Thus, the results obtained demonstrate the importance of adopting appropriate management practices associated with the selection of cultivars better adapted to the edaphoclimatic conditions of the summer in Amapá.