Study Of Heat Tolerance In Sweet Pepper Varieties

Sweet pepper is an important vegetable in China,in recent years,sweet pepper cultivation area is increasing,but less heat tolerance varieties,in summer,high temperature is the main environmental factors limiting sweet pepper production,high temperature lead to poor plant growth,so it is necessary to research deeply on the heat tolerance of sweet pepper,this experiment by five different heat tolerance of sweet pepper varieties as experimental material,respectively is 2 sweet pepper,B009F1 sweet pepper,BLN-02F1 sweet pepper,1 sweet pepper,900 F1 sweet pepper,research 25?(CK),30?,35? and 40? all sweet pepper varieties of germination,seedling stage,and flowering period related morphological index,photosynthesis,physiological index,chlorophyll fluorescence parameters and the change of the pollen viability,comparing the heat tolerance of different varieties and selecting of heat tolerance varieties,to provide theoretical basis for breeding of sweet pepper high temperature adaptability,this experiment research results are as follows:(1)germination experiment results show that:with increasing of temperature,seed germination index is a down trend,2 sweet pepper above index is higher than other varieties,and smallest drop,next is BLN-02 F1,the biggest drop in 900 F1,comparing the seed germination period,2 sweet pepper most heat tolerance,next is BLN-02 F1,the least heat tolerance is 900 F1 sweet pepper.(2)Seedling of the experimental results show that:with the increase of temperature,all varieties of plant height,leaf number,stem diameter,photosynthetic rate is a down trend,Gs and Tr rate change trend is consistent,35? the rise largest is 2 sweet pepper,40?,reduce biggest is 2 sweet pepper,only 2 sweet pepper SOD activity is rise,other varieties of SOD activity is a down trend,Every variety of Ci,POD activity,CAT activity,the content of MDA showed a trend of rise,APX activity appears rise and down trend,and the biggest rise is 2 sweet pepper,the smallest down is 900F1 sweet pepper,by comparing in seedling,2 sweet pepper most heat tolerance,next is BLN-02 F1,the least heat tolerance is 900 F1 sweet pepper.(3)flowering period the experimental results show that:with the increasing of temperature,all varieties of pollen germination rate and pollen tube length and the chlorophyll fluorescence parameters value is a down trend,2 sweet pepper above index is higher than other varieties,and the smallest drop,next is BLN-02F1 sweet pepper,the biggest drop is 900 F1,by comparing the florescence period,2 sweet pepper most heat-tolerance,next is BLN-02 F1,the least heat tolerance is 900 F1 sweet pepper.(4)the membership function was used to comprehensively evaluate the heat tolerance of different sweet pepper varieties,and the evaluation result is 2 sweet pepper most heat-tolerance,next is BLN-02 F1 sweet pepper,the least heat-tolerance is 900 F1 sweet pepper.