Associações termais e bioquímicas de Commelina benghalensis e Ipomoea purpurea sob efeito de tratamento com glifosato

Abstract

Thermal images have become an important tool in modern agriculture, enabling the efficient detection of biotic and abiotic stresses, as well as inferring physiological changes in plants. The objective was to evaluate the thermal and biochemical associations of two species of weeds under the effect of the herbicide glyphosate in conjunction with an adjuvant. In a greenhouse, three treatments of chemical management of wandering jew (Commelina benghalensis) and purple morning glory (Ipomoea purpúrea) with glyphosate and the adjuvant Matrix D were evaluated. When the plants had two to three expanded leaves, applications were made, simulating a pre-planting desiccation. The variation in leaf temperature was assessed daily using a thermal camera for six days after application. Control evaluations were conducted visually. In the laboratory, changes in the shikimic acid pathway, chlorophyll index, and dry mass were analyzed. The adjuvant Matriz D enhanced the effect of glyphosate for controlling water hyacinth and cowhorn, distinctly between species, with a faster effect on cowhorn starting from the fifth day after application. A positive correlation was observed between temperature and Superoxide dismutase (SOD) and a negative relationship between temperature and Malondialdehyde (MDA) in both species. The management with glyphosate combined with the adjuvant Matriz D showed the highest increase in leaf temperature and a greater accumulation of shikimic acid for water hyacinth. The management solely with the adjuvant, without the addition of glyphosate showed less temperature variation over time for the two weed species. There was no effect on chlorophyll and dry mass of both species.