On-Tree Methyl Jasmonate Applications: Analysis of Physicochemical and Physiological Traits of Fresh Figs After Two and Three Applications

Poster presentation at 9th Workshop GDL SOI Postharvest (Postharvest Management of Mediterranean Crops)ABSTRACTFresh figs (Ficus carica, L.) are perishable fruits with a limited shelf life. The exogenous application of elicitors during on-tree fruit development and growth is a promising strategy for improving fruit quality and shelf life. Elicitors are molecules naturally involved in plant metabolism and, when applied in low concentrations at specific points during fruit ripening, can help to improve fruit resistance to abiotic and biotic stresses. One elicitor successfully used in other crops is methyl jasmonate (MeJa). MeJatriggered during stress processes, increasing enzymatic antioxidant activity and phenolics compounds production, thereby scavenging reactive oxygen and nitrogen species. However, there are no studies on its effects on fresh figs. For this reason, an experimental trial was carried out comparing two concentrations of MeJa (0.5 and 1 mM) and their impact on the physicochemical and physiological traits of the fruit after two or three applications. Regarding physicochemical traits, differences wereobserved between two and three applications. Fresh figs treated with two applications were generally greener and brighter, corresponding to a higher chlorophyll index. However, treatments with three applications achieved the same values. About weight and size, the application of the treatments improved fruit size compared to the controls at both concentrations, with three applications treatment of MeJa 1mM producing the largest fruits. Fruits treated with two applications had higher total solublesolids and titratable acidity values, resulting in a lower ripening index. On the other hand, regarding the physiological traits of the fruit, the treatments increased the respiration rate compared to the respective controls, especially in the case of the three applications. Nevertheless, the ethylene production rate showed the opposite trend, with lower production in the treated fruits, especially in the case of the three applications.