Impact of chitosan/PVA with salicylic acid, cell wall degrading enzyme activities and berries shattering of ‘Thompson seedless’ grape vines during shelf life

Abstract

Abstract The viability of chitosan/polyvinyl alcohol (CS/PVA), mixed with salicylic acid (SA) at various doses (0, 1, and 2 mM) of ‘Thompson seedless’ grapes coating to delay fruit clusters aging during shelf life. Bunches were covered with various CS/PVA-SA treatments and placed at room temperature (26 ± 1 °C and relative humidity 46 ± 1% RH) for five days and fruit samples were picked each day. Physical and chemical of quality attributes parameters were determined to assess the impact CS/PVA-SA coating on berry quality during shelf life period (days). The physical parameters, for example, water loss, rachis browning index record, berry shattering rate, berry color (hue angle), berry separation force and firmness. Be that as it may, the chemical characteristics, for example, total soluble solids content (SSC%), titratable acidy (TA%), such phenolic compounds (add up to phenol and flavonoid content), polyphenol oxidase (PPO) beside the cell wall degrading enzyme activities: cellulase (CEL, EC:3.2.1.4), polygalacturonase (PG, EC:3.2.1.15), xylanase (XYL, EC:3.2.1.8) and cell plasma membrane permeability rate were evaluated. CS/PVA-SA 2 mM treatment reduce remarkable water loss and berry shattering and postponed the subjective change in berry color hue angle and controlled on SSC%, TA%, and SSC/TA ratio. Additionally, the progressions in TP, FL substance, and PPO activity are maintained and reduced during shelf life. Likewise, the cell wall enzyme activities (CEL, PG, and XYL) were inhibited compared with different treatments. Relationship investigation confirmed that numerous quality attributes are independent. Postharvest of CS/PVA-SA 2 mM postponed fruit clusters ripening, kept berry quality, and expanded the shelf life of 'Thompson seedless' grapes.