4种砧木对'爱媛28号'橘橙叶片光合特性及其结构影响的初步研究OACSTPCD

The influences of four rootstocks,Trifoliate orange,Carrizo citrange,Red tangerine and Citrus junos,on the photosynthetic characteristics,anatomical structure and tree growth of'Ehime No.28'orange leaves were studied.Methods such as correlation analysis and redundancy analysis were used to explore the relationship between the leaf photosynthetic performance and the anatomical structure.The results showed that both the palisade tissue and spongy tissue of'Ehime No.28'orange leaves were thicker when grafted onto Carrizo citrange rootstock.The ratio of palisade to spongy tissue in the red tangerine rootstock was the highest at 0.40 and the lowest at 0.28 for Cit-rus junos rootstock.Carrizo citrange rootstock had the highest transpiration rate and stomatal conductance,with a transpiration rate of 0.26 mmol·m-2·s-1 and a stomatal conductance of 37.67 mmol·m-2·s-1,while the red tangerine rootstock had the highest net photosynthetic rate of 1.87 μmol·m-2·s-1,and Trifoliate orange rootstock had the highest intercellular CO2 concentration of 412.67 μmol·mol-1;Red tangerine rootstock,Carrizo citrange rootstock,and Cit-rus junos rootstock exhibited higher net growth in the plant height,while Red tangerine rootstock and Citrus junos rootstock had relatively lower root-to-shoot ratios.There was a strong correlation between the photosynthetic char-acteristics and leaf structure of'Ehime No.28'orange leaves grafted onto the four different rootstocks.Redundancy analysis identified the leaf structural parameters,including the palisade to spongy tissue ratio,spongy tissue thickness,leaf thickness,upper epidermis thickness,lower epidermis thickness,and palisade tissue thickness,which signifi-cantly influenced the photosynthetic characteristics.Therefore,the palisade to spongy tissue ratio can be used as an important reference index for selecting rootstocks with different photosynthetic characteristics.