Study On Response Of Temperature Stress Cross Adaptation To Photosynthetic Physiology Of Grape Leaves

High temperature and the low temperature stress circumstance is always affecting the plant normal growth .The present research discovery temperature stress circumstance exercise is an effective method that enhances the plant resistance .Simultaneously the plant also has the cross adaptation ability. This research took the"Jing Xiu"cutting seedling as materials which were provided by Chinese Academy of Science Botanical research institute. In the paper, Under high and low temperature stress we studied the response of the heat acclimation the"Jing Xiu"cutting seedling on Photosynthetic Physiology by LI-6400 photosynthesis system, FMS-2 portable pulse modulation fluorescence and specord200 UV spectrophotometer. We will provide the theory basis in order to studying resistance cold and heat .The main results are as follows:1 Different temperature processing to grape seedling photosynthesis influence. Take the"Jing Xiu"cutting seedling as the materials, we has studied the influence on different temperature to the grape seedling chlorophyll fluorescence characteristic as well as the photosynthesis characteristic,The chlorophyll fluorescence parameter result indicated: compare 27℃processing grape seedlings with 38℃processing grape seedlings, the grape seedlings PSII activity was optimum in the sub temperature (38℃)sustained 12 hours . The photosynthesis parameter result indicated, 38℃processing grape seedlings photosynthesizes was slight lower than 27℃processing grape seedlings. Although the net photosynthesis has reduced, it was a little influence to the grape seedlings; contrarily it stimulates PSII the activity.2 Under high and low temperature stress the heat acclimation grape seedlings effect photosynthesis and enhance its thermal resistance. and the cold resistance research. The heat acclimation(38℃)and Non- acclimation(27℃) from"Jing Xiu"were used as materials. We studied effects of chlorophyll fluorescence parameter and photosynthesis index by heat(44℃)and cold (-4℃) stress. The chlorophyll fluorescence parameter result indicated: the minimal fluorescence (Fo) and Non-Photochemical quench(qn) in heat acclimation and Non- acclimation also increased with stress time past ,but heat acclimation was less than Non- acclimation. PSII maximal photochemical efficiency (dark Fv/Fm), PSII maximal photochemical efficiency (light Fv'/Fm'),PSII actual photochemical efficiency (∮PSII), PSII potential photochemical efficiency (Fv/Fo) ,and photochemical quench(qp) in heat acclimation and Non- acclimation decreased with stress time go, but heat acclimation was higher than Non- acclimation. The photosynthesis parameter result indicated:the net photosynthesis(Pn) in heat acclimation and Non- acclimation decreased with stress time go, but heat acclimation was higher than Non- acclimation.3 Under high and low temperature stresses the heat acclimation to antioxdase System influence. the high temperature exercise obviously enhanced the grape seedlings catalase (CAT) and antiscorbutic acid specific peroxide enzyme(APX) and decreased the content of Malondialdehyde(MDA).Therefore, as can be seen, the high temperature exercise enhanced grape seedling's thermal resistance, the grape seedling has had the cross adaptation, and the cold resistance also obtained the enhancement at the same time.