EFFECTS OF PREHARVEST TREATMENTS IN ANTHOCYANIN CONTENT AND RED DRUPELET REVERSION OF BLACKBERRIES (Rubus sp.)

Abstract

Blackberries (Rubus sp.) are one of the fastest growing products in the Mexican agricultural sector, its popularity is due in part to. It’s high content of antioxidant and bioactive compounds. Among them are anthocyanins, which give the intense purple coloration characteristic of blackberries. This fruit is highly susceptible to a physiological disorder known as reversion, which is linked to anthocyanin degradation and is manifested as a color change and the formation of spots. The condition damages consumer perception of fruit quality and is one of the main reasons for rejection during fresh blackberry marketing.
Anthocyanin synthesis and degradation are regulated by external and internal stimuli including the effect of growth regulating substances. In this sense, the use of chitosan and salicylic acid, two substances widely reported as plant metabolism modifiers, offers an option to increase the concentration or maintain the integrity of anthocyanins present in blackberry fruits. The objective of this work was to describe the effect of foliar application of 3 mM salicylic acid and 0.25 % chitosan in pre-harvest periods on total anthocyanin content and the occurrence of the reversion phenomenon in blackberry fruits. The results showed an increase in anthocyanin content in blackberries treated with chitosan and a decrease in the occurrence of the reversion phenomenon in blackberries treated with chitosan and salicylic acid after 144 hours of storage.