福安产区不同海拔'巨峰'葡萄叶绿素荧光和果实品质的差异分析OA

To investigate the physiological and ecological responses of'Kyoho'grapes to natural summer heat stress at different altitudes,'Kyoho'grapes from the Fu'an growing region were used as experimental materials.Chlorophyll fluorescence parameters were measured at three altitude sites—10 m(T1),460 m(T2),and 680 m(CK)—under natural high-temperature conditions(＞38℃)that persisted for three consecutive days.Additionally,differences in soil pH,electrical conductivity(EC),root zone temperature at a 10 cm soil depth,root distribution,and fruit quality were compared among the three sites.The results showed that under natural summer high-temperature conditions,the soil pH and electrical conductivity at the 680 m altitude site were the lowest among the three sites,indicating the lowest soil salinity.The root zone temperature at a 10cm soil depth in this site was significantly lower than that at the 10m and 460m sites,with an average reduction of 2-3℃.The total root mass across the sites was ranked as 10 m＞680 m＞460 m,but the 680 m site had the highest proportion of fine roots(≤2 mm).Intrinsic fruit quality indicators such as ester content,soluble solids,and the solid-to-acid ratio were ranked as 680 m＞460 m＞10 m.Under identical high-temperature conditions,the 680 m altitude site exhibited a lower decline in Fv/Fm over two consecutive days compared to the 10 m and 460 m sites.The results of the chlorophyll fluorescence parameters indicate that under continuous high-temperature conditions,the PSII reaction centers,light-harvesting pigments,photochemical efficiency,and oxygen-evolving complexes in grape leaves at the 680 m elevation site suffered less damage,demonstrating stronger adaptability to high-temperature environments,and the fruit from this region exhibited superior intrinsic quality.In summary,the 680 m elevation area is a more suitable cultivation region for'Kyoho'grapes under summer high-temperature conditions in the Fu'an production area.