Polyphenol and Quality Attributes from Some Potato Cultivars and it's Affected by Date of Planting and Salicylic Acid Treatments

In This study we assess the effect of planting dates and salicylic acid treatments on the phytochemical content on tubers peel and flesh of potato cvs. Lady Rossetta, Burn and Cara.Three planting times; September 12th, September 26th and October 12th. Two concentrations of salicylic acid (control,100 and 200ppm) were used as foliar spray on potato cultivars. Obtained data revealed that earlier planting dates of 12th and 26 September with potato cv. Burn shows the highest increase in polyphenol and flavonoids content both in flesh (57.83 and 65.05 mg/100gFW) and peel (92.02 and 219.57mg/100gFW) gives the highest values for non-reducing sugar and total sugar content with cv. Cara, and gives the highest accumulation of anthocyanine content in peel and flesh color lightness (L*) with potato cv. Lady Rossetta. Salicylic acid at a concentration of 200ppm was effective for increasing flavonoids content, reducing, non-reducing sugar and total sugar content of tubers. While, the concentration of 100ppm was effective with polyphenol content and accumulation of anthocyanin in the peel of potato tubers. Concerning the interaction effect. Lately planted on Oct. 12th of potato cv. Cara without SA spraying or planted early at Sept. 12th with SA 200ppm increased polyphenol content, non- reducing and total sugar content % cv. Burn recorded the highest increased in flavonoids content in peel at SA 200 ppm and in flesh at 100ppm. Potato cv. Lady Rossetta at SA 200ppm registered the best values for accumulation of anthocyanin content in the peel and lightness of tuber flesh color (L*).