The Photosynthetic Physiology And Cultivar Evaluation Of Five Blueberry Cultivars In Jilin And Hubei Province

This paper investigates five cultivars of blueberries,including‘O’neal’,‘Misty’,and‘Northland’in Anju,Hubei Province,and‘Toro’,‘PLJY-2’and‘Northland’from Jingyu,Jilin Province.The author studies the tree growth potential,leaf morphological characteristic,chlorophyll content,leaf anatomical structure,fruit quality and photosynthetic physiological characteristics of these five cultivars of blueberries,and gives a comprehensive evaluation as follows:1.Anatomical structure of the leaves:the main vein thickness of‘PLJY-2’is 802.10μm,the leaf is 224.21μm,the upper epidermis is 23.42μm,the lower epidermis is 13.68μm,and the spongy tissue is 148.50μm,which are significantly thicker than‘Toro’and‘Northland’.On the other hand,the leaf thickness of‘Misty’is 251.22μm,the cuticle is 3.42μm,the upper epidermis is17.36μm,and the spongy tissue is 133.77μm,which are significantly thicker than‘O’neal’and‘Northland’.2.In the aspect of basic photosynthetic parameters:first,the Pn of‘Toro’is 4.40μmol·m^-2·s^-1,significantly higher than‘PLJY-2’and‘Northland’.Second,the Ci of‘Toro’is266.33μmol·m^-2·s^-1,significantly higher than‘PLJY-2’and‘Northland’.Moreover,the E of‘PLJY-2’is 3.53μmol·m^-2·s^-1,significantly higher than‘Toro’and‘Northland’.Finally,the Pn of‘Northland’is 2.56μmol·m^-2·s^-1,which is lower than‘O’neal’and‘Misty’.3.As for the light response curve:the Pn-PAR curves,E-PAR curves and Gs-PAR curves of these five cultivars of blueberries tend to be consistent.The Ci-PAR curves are decreasing with the sun luminous intensity.The LSP of these five cultivars of blueberries ranges from 668.65 to1027.38μmol·m^-2·s^-1.‘Toro’and‘Northland’is significantly higher than‘PLJY-2’,while‘Misty’is higher than‘O’neal’and‘Northland’.The LCP of these five cultivars of blueberries ranges from 45.58 to 85.27μmol·m^-2·s^-1.‘Toro’and‘PLJY-2’is significantly lower than‘Northland’,while‘Misty’is lower than‘O’neal’and‘Northland’.4.With regard to the appearance quality:the fruit shape index of these five cultivars of blueberries in the two area is distributed among 0.66⁰.75,all of which are oblate fruits.‘Toro’’s fruit shape index is the smallest with the average value of 0.66,and the signle fruit quality was the largest with the average value of 4.45g.Therefore,‘Toro’is the super-large class of blueberry.On the other hand,‘Misty’has the highest content of soluble solids,with an average of 12.96%.‘Misty’is the heaviest by single one,with an average of 2.61.It is the big class of blueberry.5.The internal quality:the soluble sugar and soluble protein in‘Toro’are higher than in‘PLJY-2’and‘Northland’.The total phenolic and flavonoids in‘Northland’are higher than that in‘Toro’and‘PLJY-2’.The soluble sugar,titratable acid,soluble protein,total phenolic and flavonoids of‘Misty’are more than that in‘O’neal’and‘Northland’.6.The evaluation:The‘Northland’gradually entered the high yield period after the third year.It shows a strong tree growth potential and photosynthetic physiological,and gives high yield with good quality.As for‘Toro’,the resistance is poor and the branches are easy to break.While‘PLJY-2’presents strong photosynthesis and the fruits have high nutrition.And the fresh‘O’neal’is of high quality,but it tends to crack severely in rainy days.The fruit quality index of‘Misty’is outstanding,and yields well.However,flower and fruit thinning should be done in time.