Study On The Physiological And Biochemical Characters Of Cashew Cold Resistance

Low temperature is the key environmental factor that effects the growth andgeographic distribution of the plant, it’s a kind of disaster often encounter in plantcultivation, which can cause serious production losses. Cashew belongs to Anacardiumof Anacardiaceae, is a typical tropical evergreen fruit tree, and it’s one of the world fourfamous dry fruits. In recent years, the occurrence of extreme weather has caused seriousdamage to cashew production. However, the current research on cashew mainly focusedon high yield cultivation, germplasm resources collection and preservation, cultivation ofnew varieties and so on, the reported study about cashew cold resistance was few.In this paper, eight cashew adult blade were employed as experimental materialunder artificial low temperature stress and5cashew family seedlings were used asexperimental material under natural low temperature stress, tested their physiological andbiochemical indices of cold resistance, such as the relative electrical conductivity, thecontent of MDA, soluble sugar, proline and the activity of SOD after low temperaturetreatments. Used the subordinate function and cluster analysis as comprehensiveevaluation methods to make comprehensive evaluation on the cold resistance of the eightcashew plants to select the strong cold resistance plant. The study aimed to explore thephysiological response mechanism of cashew under low temperature stress, furtherillustrate cashew cold resistance mechanism and provide scientific basis for the selectionof strong cold resistance plants. The results showed that:1. According to the measured result of physiological and biochemical indices ofcold resistance after low temperature stress, the material was divided into threecategories by subordinate function and cluster analysis. The sample8#、9#and10#showed the strongest cold resistance; the sample3#and7#showed medium coldresistance; the sample4#、5#and6#showed the worst cold resistance.2. Through artificial low temperature stress experiments, found that the strongestcold resistance cashews were the re-grow plants which the trunk had died by chillinginjury. The result had an important meaning for further research about cold resistancemechanism and the selection of cold resistance plant.3. Correlation analysis was performed according to the measured result of physiological and biochemical indices of cold resistance after low temperature stress.The results showed that: the physiological and biochemical indices of cold resistance hadcomplex relationship. The relative electrical conductivity, the content of MDA, solublesugar, proline and the activity of SOD can be used as cold resistance evaluation index.4. The variance analysis showed that: the difference between materials, differentstress temperatures and different stress times were significant under artificial lowtemperature stress.5. The law of physiological and biochemical indices were different betweenartificial and natural low temperature stress. There were three reasons: first, thephysiological response of cold resistance of isolated leaves and living plant leaves weredifferent; second, the cold resistance of adult leaves and seedling leaves were different;third, the deposal condition of low temperature were different.