Effects of BA and TDZ on postharvest quality and expression of laccase and aquaporin genes in cut rose ‘Sparkle’

Abstract

This experiment was conducted to study the effects of BA and TDZ on postharvest quality of cut rose ‘Sparkle’ and expression of Laccase and Aquaporine genes. The concentrations of TDZ at 25 and 75μM and BA at 150 and 300μM were applied for 24h as pulsing, while control cut roses received neither TDZ nor BA. TDZ with 25 and 75μM increased the longevity of flowers 1 and 2.8days respectively, compared to control. Furthermore, TDZ in both concentrations showed significant difference in flower quality. 150μM BA showed less adverse effects on display quality than 300μM BA. In fact, applying 300μM BA resulted in early petal senescence and bent neck. Expression patterns of Aquaporin (RhTIP), and Laccase (RhLAC) genes were investigated in leaves received 75μM TDZ and 150μM BA, as well as control treatment. The result showed that 150μM BA induced the expression of RhLAC gene, while TDZ had no significant impact on RhLAC transcription expression level. Expression of RhTIP was neither affected by BA nor by TDZ. These results suggest that decline of postharvest quality and increase in the expression of RhLAC under BA treatment could be related to BA-induced stress affecting the endogenous ethylene production in cut rose cv. Sparkle. In contrast to TDZ which prolonged postharvest quality of cut rose cv. Sparkle, BA decreased the longevity of flowers concomitantly with appearing necrosis symptom on petals.