Studies On Heat Resistance In ’Ganmi 6’ Kiwifruit (Actinidia Eriantha Benth)

High temperature stress in summer is one of the key factors to control the growth of kiwifruit.The selection of heat tolerance varieties is of great significance to the sustainable development of kiwifruit industry.Actinidia eriantha Benth is an our country unique germplasm resources,‘Ganmi 6’ is selected from natural variation group of wild A.eriantha Benth,which performs strong heat resistance in fileds.So,used A.eriantha Benth variety ‘Ganmi 6’ as research materials,A.chinensis and A.deliciosa main variety as contrast,studied effects on physiological indexes related to heat resistance under high temperature stress in this paper systematically.And conducted correlational analysis of physiological indexes related to heat resistance.Comprehensive comparison analysised heat resistance of ‘Ganmi 6’ and control kiwifruits’ reunioned membership function,factor analysis and principal component analysis.In order to provide theoretical foundation for illuminating physiological mechanism of heat resistance in A.eriantha Benth.As follows are mainly research results:(1)Used seedlings of ‘Ganmi 6’as research materials,and ‘Lushanxiang’ as control materials,studied the changes of heat tolerance related physiological indexes under high temperature stress,and the study found that chlorophyll of ‘Ganmi 6’ and control kiwifruit all degradated,while content of MDA,proline and soluble protein added under high temperature stress.Appropriate high temperature may accelerate activity of POD and CAT.Could increase the ability of reactive oxygen,we found that the degradation rate of chlorophyll and amplification of MDA content in ‘Ganmi 6’ were less compared with‘Lushanxiang’,while amplification of proline and soluble protein content and activites of POD,CAT and SOD were more than that in ‘Lushanxiang’.Which indicated that heat resistance in ‘Ganmi 6’ was stronger.It showed that chlorophyll had a negative correlation with other physiological indexes,and the others had a positive correlation with each other in seedlings of ‘Ganmi 6’ by means of correlation comparative analysis.Physiological indexes related to heat resistance in seedlings of ‘Lushanxiang’ presented different correlations,especially in stress resistance enzyme presented negative correlations.The results tell us that physiological indexes related to heat-resistance in kiwifruits exsited correlations while that were inconformity in different verieties.(2)Diurnal variation of photosynthesis and chlorophyll fluorescence characteristics in A.eriantha Benth variety ‘Ganmi 6’,A.chinensis variety ‘Hongyang’ and ‘Jinyan’,A.deliciosa variety ‘Jinkui’ were tested in fileds in summer high tempertare condition.The results found that high temperature stress not only led to reduce of net photosynthetic rate,stomatal conductance and transpiration rate,concentration of CO2 in cells rising in kiwifruit leaves,but also rising Fo,Y(NPQ)and qN,decresing Fm、Fv/Fm,Fv/Fo,ETR and Y(Ⅱ)in chlorophyll fluorescence characteristics.‘Ganmi 6’ had higher photosynthetic rate and lower transpiration rate,leaves PSⅡreactive center appeared least irreversibledegree of damage,highest electron transfer activty,and least diurnal amplitude of qN variation in high temperature condition.Which indicated that ‘Ganmi 6’ was influenced least by stress in high temperature condition.(3)A.eriantha Benth variety ‘Ganmi 6’,A.chinensis variety ‘Lushangxiang’,‘Hongyang’ and ‘Jinyan’,A.deliciosa variety ‘Jinkui’ planted in Fengxin germplasm nursery were used as text materials in summer high tempertare condition.The study found that chlorophyll degraded,electrical conductivity enlarged,MDA,proline and soluble protein largely accumulated in four varieties of kiwifruits under high temperture stress.At the same time,we also found that under appropriate high temperture stress,activities of POD,CAT and SOD in four kiwifruits leaves enhanced.Combined membership function analysis it showed heat-resisting capacity in four varieties of kiwifruits: ‘Ganmi 6’ >‘Jinkui’ > ‘Jinyan’ > ‘Hongyang’,the results were basically matched with their expression in production,also indicated that membership function can avoid one-sidedness of single physiological index related to heat-resistance,and evaluated heat-resistance in kiwifruits roundly.(4)Annual matural seedling of A.eriantha Benth variety ‘Ganmi 6’,A.chinensis variety ‘Hongyang’ and ‘Jinyan’,A.deliciosa variety ‘Jinkui’ planted in Fengxin germplasm nursery were used as text materials,which showed the same results with the text in summer high tempertare condition.Direct at that evaluated heat resistance of plants by membership function may cause deviation,this research indicated heat-resisting capacity by principal component analysis in four varieties of kiwifruits: ‘Ganmi 6’ >‘Jinkui’ > ‘Jinyan’ > ‘Hongyang’,the results were basically matched with their expression in fields.