Effect Of Some Exogenous plant Hormones On Biochemical Constituents Of Potato plants

Egypt is considered one of the ten largest potato exporting countries. The exported amount reached more than 150.000 tons a year . The total cultivated potato area is being increased along the last 20 years . In 1963 the cultivated aera was 59.822 feddanes , whereas in 1989 it reached 180.000 feddans ( Hortculture Research Institute, Potato Research Department, Ministry of Agri. Egypt ). Growth regulators have been the focus of numerous studies . Most studies were cocerned with the favourable effect of these regulators on the growth, yield and quality of plants . The present investigation is concerned with the effect of Kinetin ” N6- furfural amino purine ” ; growth regulator and Alar or ( B-9 ) ( N-N dimethyl ammonium succinemic acid ) ; as growth retardent, on some biochemical compounds in potato tubers and leaves, as well as some enzyme activities such as B- amylase, phosphorylase and polyphenol oxidase . Also The Pesent investigation was conducted with the aim of testing the effect of kinetin or alar on the metabolic changes in potato tubers during storage and its keebing quality during storage after harvesting.