Field management of yellow melon (Cucumis melo L.) with silicon sources

This study aimed to evaluate the effect of silicon and acibenzolar-S-methyl sources on the development of yellow melon (Cucumis melo L.) in the field and the occurrence of diseases in different years. The treatments consisted ofthe silicon sources Agrosilício® (3 g L−1), Rocksil® (3 g L−1), and Chelal® Si (2 L 100 L−1), the additional treatments acibenzolar-S-methyl (ASM) (2 mM) and the fungicide thiabendazole (400 mL 100 L−1), and a control (sterile distilled water). The following characteristics were evaluated: natural incidence of diseases; gas exchange: CO2 assimilation rate, transpiration, stomatal conductance, internal CO2 concentration, water use efficiency, instantaneous water use efficiency, and carboxylation; postharvest aspects: fruit weight, pulp thickness, pulp firmness, titratable acidity, pH, soluble solids, and vitamin C content; productivity; and the enzymatic activity of peroxidases, polyphenol oxidases, and phenylalanine ammonia-lyase. No significant response was observed for naturally occurring diseases. Treatments with Chelal®Si, Rocksil®, and Thiabendazole® increased photosynthetic and transpiration rates in the yellow melon. The silicon and ASM sources did not influence the physicochemical characteristics or the enzymatic activity of fruits. No effect was observed on the biometric characteristics, productivity, and chemical quality of fruits in both years of cultivation. Si sources increased photosynthetic rate and transpiration. However, no diseases were observed during the experimental period. Leaf spraying with silicon and acibenzolar-S-methyl sources did not influence the biometric characteristics and fruit production of yellow melon. The silicon and acibenzolar-S-methyl sources did not induce an increase in the enzymatic activity of peroxidases, polyphenol oxidase, and phenylalanine ammonia-lyase. Fruit production was higher in 2020.