不同果锈等级的阳光玫瑰葡萄果皮结构及相关物质变化

Changes in Berry Peel Structure and Related Substances of Shine Muscat Grape with Different Berry Russet Levels

为了探明阳光玫瑰葡萄果锈形成的生理机制,以8年生阳光玫瑰葡萄植株为试验材料,在果实进入软化期后,研究不同果锈等级的果实果皮组织结构、细胞膜透性、细胞壁与果锈相关物质含量及相关酶活性的变化。结果表明,果锈首先发生在细胞间隙和细胞壁上,细胞结构凸显,之后逐渐向细胞内部蔓延,褐化范围和细胞间隙增大,果皮表面凹凸不平,严重时果锈渗透整个细胞。随着果锈等级的增加,果皮细胞膜透性逐渐增加,果锈等级3及以上的细胞膜渗透率显著增加,达到77%以上;纤维素、半纤维素和原果胶含量逐渐降低,木质素和总酚含量逐渐升高,且果锈等级1及以上的木质素和总酚含量显著增加,分别达到161.3 mg/g和1.29 mg/g以上;纤维素酶和酸性磷酸酶活性先升高后降低,碱性磷酸酶和过氧化物酶活性先降低后升高,苯丙氨酸解氨酶活性逐渐升高,多酚氧化酶活性逐渐降低。总之,阳光玫瑰葡萄果锈的形成是细胞壁结构的降解和木质素等果锈物质的积累过程,苯丙氨酸解氨酶是调控其果锈形成的关键酶。

In order to explore the physiological mechanism of berry russet formation in Shine Muscat grape,eight-year-old Shine Muscat grapevines were used as experimental materials to study the changes of berry peel structure,cell membrane permeability,cell wall and berry russet substance content,and related enzyme activities at different berry russet levels after softening stage.Results showed that berry russet occured in the intercellular space and cell wall first,and the cell structure became obvious.Then it spreaded into the cell gradually.Meanwhile,the browning range and cell space increased,and the peel surface was uneven.It penetrated into the whole cell when berry russet was severe.With the increase of berry russet level,the permeability of cell membrane increased gradually.The cell membrane permeability of berry russet levels 3 and 4 increased significantly,which reached above 77%.Meanwhile,the contents of cellulose,hemicellulose and protopectin decreased gradually,and the contents of lignin and total phenol increased gradually.And the contents of lignin and total phenol at berry russet levels 1,2,3 and 4 increased significantly,which reached 161.3 mg/g and 1.29 mg/g or above,respectively.Furthermore,the activities of cellulase and acid phosphatase increased first and then decreased with the increase of berry russet level.The activities of alkaline phosphatase and peroxidase decreased first and then increased.The activity of phenylalanine ammonia-lyase increased gradually.The polyphenol oxidase activity decreased gradually.In conclusion,the formation of berry russet in Shine Muscat grape is a process of the degradation of cell wall structure and the accumulation of lignin and other berry russet substances.The phenylalanine ammonia-lyase is the key enzyme to regulate the formation of berry russet of Shine Muscat grape.