日灼对酿酒葡萄‘霞多丽’果实品质与解剖结构的影响

Impacts of Sunburn on the Anatomical Structure and Quality of Chardonnay Grape Berry

以酿酒葡萄品种‘霞多丽’为试验材料,采用石蜡切片与CFDA荧光染色观察日灼果皮细胞结构与细胞活性变化,同时测定日灼发生后葡萄果实品质及相关生理指标变化,以揭示日灼对果实品质与细胞结构的影响。结果表明:(1)随着葡萄日灼病加重,果实表皮颜色由浅黄色逐渐加深,后期甚至出现细胞坏死。(2)果实发生日灼后,果实硬度与含水量下降,细胞壁含量增加,果皮从外向内第1~3层细胞明显变小,细胞壁增厚。(3)随着日灼病加重,果皮细胞破裂,且破裂数量增加,细胞活性也随之下降,果皮保护功能逐渐丧失,果肉细胞逐渐失水导致了果实皱缩;重度日灼果实周缘维管束木质部导管受到果皮细胞失水断裂的影响,出现断裂变形。(4)在葡萄果实日灼发生过程中,受到高温与强光照胁迫影响,同时伴随着水分散失增加,果实可溶性固形物含量和总糖含量增加,但有机酸含量降低,糖酸比随之增加;以上各品质指标值的大小与果实水分含量密切相关。研究发现,日灼引起了葡萄果实结构变化与生理代谢的紊乱,随着日灼程度加重,果皮细胞逐渐死亡,果实内水分大量散失,果实糖含量增加,严重影响了葡萄果实的外观和内在品质。

With the cultivar Chardonnay grapevine（Vitis vinifera L.）as material,the methods of paraffin section and CFDA dye labeling were used to observe the structure of grape berry and the cell death in grape berry skin,berry quality and relative physiological indexes were also measured,in order to make clear the effects of sunburn on grape berry quality and berry structure.The results showed that：（1）The sunburn of berry was characterized by light brown lesions from initial phase,and then the lesions increased in size and depth of color with the increasing of sunburn severity.For the severe sunburn in chardonnay grapes,the dark brown lesions were seen and associated with cell death in the berry skin.（2）When the berry was damaged by sunburn,berry firmness and water contents decreased,but the cell wall contents increased.The epidemic cell size of grape berry with sunburn was smaller than that with no sunburn,but the epidemic cell wall of sunburn berry was thicker than that with no sunburn.（3）With the increase of sunburn se-verity,the epidemic cell wall broke,and the cell activity decreased.Due to the loss in protecting function of berry skin,the grape berry shrunk gradually with the increasing of sunburn severity.In addition,for the grape berry with severe sunburn,the xylem vessel in dorsal vascular bundle cracked.（4）The occur of sunburn was associated with the water loss of grape berry,TSS（total soluble solids）and total sugar content of grape berry increased,but the content of organic acids decreased.Sunburn induces the changes in grape berry anatomy and disorder of physiological function,with the increase of sunburn damage to berry,the cells of berry skin died gradually.Because of water loss in grape berry,the TSS and sugar contents also increase in grape berry,but the impacts of sunburn on the wine quality should be further studied for the wine grape production.