Studies On Enzyme Activities Relating To Potato Processing Trait

The thesis deals with the studies on dynamics of enzymes activity about potato processing trait in two aspects. One is on PPO's activity in all the time of potato and the other is on the activities of AGPase, UGPase, IV and PPO of test-tube potato plantlet.The test of the PPO's activity of five culture potato varieties in different growing stages shows as following:(1) The leaves PPO's activities are different in different varieties, but the trends are similar: the maximum activity appears from alabastrum forming to tuber developing.(2) During blooming PPO's activities appears greater difference in different tissues and organs. The anther PPO's activities are maximum, followed sequently by stoloniform stem, alabastrum, petal, leaf, tuber and anther.(3) PPO's activities in tuber of different varieties and different developing periods are different greatly. The enzyme activities in tuber of progenesis and later developing are higher than in rapidly forming, and in exadermis are higher than in intermediate tissue and medulla. The enzyme activities are increased in both tuber stored in low temperature and in normal temperature. The buds appear higher enzyme activities than stored tuber does.The enzyme activities in three medium breeding materials and tow potato varieties show as following:(1) As for AGPase, of test-tube potato plantlet leaves of 114 is the highest in three medium breeding materials. It reaches to 2.35umolGlc-6-Pg~lFWh~l. 114 have higher capability of starch synthesis.(2) As for UGPase, enzyme activities of test-tube potato plantlet tuber in all materials are increased in variant degrees. In three medium breeding materials, average enzyme activity of SKI 3 is the lowest, and the changes are slower.(3) As for IV, in normal temperature stored material enzyme activities change very small, yet in low temperature, the enzyme activities are all increased. Favorita and 114 appear low enzyme activities and slower varieties.(4) As for PPO, enzyme activities of test-tube potato plantlet leaves in all materials are not significantly different. In tuber SKI3 appears the maximum enzyme activity and 102 appears the minimum.