河套蜜瓜果实发育过程中糖积累与蔗糖代谢相关酶的关系  

Relationship between Sugar Accumulation and Its Metabolizing Enzymes during Muskmelon Fruit Development

作　　者：张中霞[1] 刘艳[1] 白立华 蔡贵芳[1] 

机构地区：[1]内蒙古农业大学农学院,呼和浩特010019 [2]内蒙古巴彦淖尔农业科学院,内蒙古巴彦淖尔015400

出　　处：《西北植物学报》2011年第1期123-129,共7页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金项目(30860180);内蒙古自然科学基金项目(200711020314)

摘　　要：以河套蜜瓜为试材,采用外部形态观测与内部生理指标测定相结合的方法,对其果实发育过程中果实生长模式以及果实中蔗糖、果糖、葡萄糖和淀粉含量以及蔗糖代谢相关酶活性进行测定,以揭示河套蜜瓜果实生长发育过程中糖的代谢积累与相关酶的关系.结果显示:(1)河套蜜瓜果实生长速率呈单"S"曲线,果实发育早期以积累葡萄糖为主,进入成熟期后蔗糖积累量迅速增加,最终由蔗糖和己糖共同构成果实品质.(2)在河套蜜瓜果实成熟期前,蔗糖磷酸合成酶(SPS)活性维持较低水平,进入成熟期后,SPS活性迅速升高;蔗糖合成酶(SS)活性在成熟期前为分解活性大于合成活性,成熟期后表现为合成活性大于分解活性;在整个果实发育期,酸性转化酶(AI)活性较低,中性转化酶(NI)活性始终高于AI.(3)在果实整个发育期,蔗糖含量与蔗糖代谢酶的净活力呈极显著正相关,蔗糖代谢相关酶共同作用决定果实中蔗糖含量.研究表明,在河套蜜瓜果实发育前期,以蔗糖分解代谢为主,且蔗糖合成酶和中性转化酶是催化蔗糖分解的关键酶;果实成熟期间,蔗糖代谢转为合成方向为主,蔗糖合成酶和蔗糖磷酸合成酶在蔗糖积累中起主导作用.The changes of growth phase,sucrose,glucose,fructose,starch and the activities of sugar metabolism-related enzymes in Muskmelon fruit development（Cucumis melo L.cv.Hetao） were determined to study the relationship between the sugar accumulation and its metabolizing enzymes in Hetao.The results indicated that：（1）the growth curves of Hetao showed single sigmoid pattern;The fruit of Hetao mainly accumulated glucose in the early stage;sucrose accumulated rapidly in mature period,finally accumulation of sucrose and sugar together constituted the fruit quality.（2）The activity of sucrose phosphate synthase（SPS） was low before mature period,the activity of SPS increased rapidly in mature period.The sucrose synthase（SS） activity on cleavage direction was higher than that on the synthetic direction before mature period and the sucrose synthase（SS） activity on synthetic direction was higher than that on the cleavage direction in mature period.The acid invertase（AI） activity was low in the developing Hetao,the neutral invertase（NI） activity was higher than that of the acid invertase（AI）.（3）Throughout the whole fruit development,the content of sucrose had significant positive correlations with net activity of the enzymes.It showed that the combined action of sugar metabolism-related enzymes decided the content sucrose of fruit.Through correlation analysis that each of the enzyme activity,dynamic change,the correlation of sugar,sucrose metabolism is the main catabolism in the early stage.The activities of the sucrose synthase and the neutral invertase（NI） were main enzymes in sucrose decomposition in the early stage;sucrose metabolism turn to synthetic direction in mature period,the activities of the sucrose phosphate synthase and the sucrose synthase played a leading role in sugar accumulation.

关 键 词：河套蜜瓜 糖积累 蔗糖代谢酶 

分 类 号：Q945.65[生物学—植物学]