Study On Selection Of Strawberry Varieties And Photosynthetic Change In Facilities

Through the selection research of strawberry varieties and soilless culture substrates in soilless culture,the strawberry varieties and soilless culture substrates suitable for the soilless culture of protected strawberry are selected,further research on the photosynthetic diurnal variation of selected strawberry varieties,which provide theoretical basis for the establishment and research of the strawberry soilless culture technical system.The results are as follows:（1）Soilless cultivation matrix ratio screening test:The strawberry variety06-L87-1 was used as the test material to prepare 10 kinds of soil free culture substrates,including peat,vermiculite,coconut bran and perlite in different proportions.The effects of different matrix ratio on the biological characters,photosynthetic characteristics and fruit quality of strawberry were studied.The results showed that strawberry grew well under S7 treatment,and its plant height and leaf area were higher than those of other treatments.By analyzing the photosynthetic characteristics of strawberry leaves,the net photosynthetic rate,chlorophyll a,chlorophyll b,total chlorophyll,carotenoid and relative chlorophyll content of S7 leaves were all higher than those of other treatments.The comprehensive analysis showed that the photosynthetic performance of S7 was the best.In terms of fruit quality,S7 treated soluble solids,solid acid ratio and average fruit weight were higher than those of other treatments.The nutritional growth,photosynthetic performance and fruit quality indexes of strawberry plants were analyzed.It was found that the mixture ratio of vermiculite:coconut:coconut bran=2:1:1was the best matrix,which could be used as the substrate for the cultivation of strawberry.（2）Variety comparison test:Seven strawberry cultivars from Japan were used as materials.Using the membership function method to determine the biological characters,photosynthetic characteristics and fruit quality of different varieties of strawberry,which would help enrich the strawberry cultivars of Tianjin.The result showed that the difference of biological characters,photosynthetic characteristics and fruit quality among different strawberry varieties was obvious.Through the analysis of the membership function values of the net photosynthetic rate,leaf area,average fruit weight,soluble solids,soluble sugar,sugar-acid ratio and hardness,it is concluded that Jiaomei has strong photosynthetic capacity,sweet and sour fruit,high hardness,suitable for storage and transportation,which is the most suitable for popularization and cultivation.（3）Diurnal variation of photosynthesis in different strawberry varieties:Strawberry Cultivar Jiaomei and Hongyan were used as experimental materials,and the changes of strawberry sunning were studied.The results showed that the daily variation curve of net photosynthetic rate of 2 varieties of strawberry was Shuangfeng type,and there was a phenomenon of"noon break"of photosynthesis at the same time.The peak occurrence time of the 2 varieties was basically the same,the highest peak appeared at about 10:00,and the peak at 14:00 reached second peaks,However,the peaks of Hongyan were 4.27 and 1.33μmol·m^-2·s^-1lower than Jiaomei.The diurnal variation curves of stomatal conductance and transpiration rate of the 2 varieties were all Shuangfeng type.The variation curve of intercellular CO₂concentration decreased first and then reached second peaks at 12:00,then began to decline,and gradually rose after 14:00.The net photosynthetic rate and the change of intercellular CO₂concentration were negatively correlated.The comprehensive analysis showed that the Jiaomei photosynthetic ability is stronger than Hongyan.