Overcoming phenolic accumulation of date palm in vitro culture using α-tochopherol and cold pre-treatment.

Shoot tips were excised from offshoots of superior male date palm and in vitro cultured on Muarshige and Skoog (MS) medium. Different antioxidant substances (vitamin E, ascorbic and citric acids) with different concentrations were tested on shoot tips browning, swelling and callus induction. In addition, cold pretreatment at 5°C for three or five days with or without soaking in antioxidants were investigated. Results showed that, soaking of shoot tips in vitamin E before in vitro culture enhanced swelling and reduced browning. Moreover, keeping the explants for 3 days at 5°C decreased browning percentage and improved swelling records. Vitamin E as well as cold pretreatments enhanced callus induction significantly.