| 摘要: |
| [目的]揭示南瓜果实发育过程中糖分积累以及相关酶活性的变化规律.[方法]以“红香栗”、“黄狼”、“蜜本”3个南瓜品种为试材,对花后1～8周果实内的果糖、葡萄糖、蔗糖、淀粉等营养成分含量及相关酶活性进行了研究.[结果]随着果实的迅速成熟,“黄狼”和“蜜本”的己糖总量持续下降,收获前才略有升高,“红香栗”的已糖含量在花后第3周之前有一段上升过程,随后迅速下降,果实成熟时3个品种的己糖含量相差不大.“黄狼”中中性转化酶活性呈单峰变化,“红香栗”和“蜜本”为双峰变化.“黄狼”和“蜜本”蔗糖磷酸合成酶活性变化趋势相似,都有2个高峰,分别出现在授粉后的第4周和第6周,第6周后逐渐降低.“红香栗”淀粉磷酸化酶活性的变化呈明显双峰型,高峰出现在第2周和第4周;在前6周,“蜜本”的淀粉磷酸化酶活性一直在7.6μg/(g·min)上下浮动,到第7周迅速下降到最低点,此后又急剧上升;“黄狼”的淀粉磷酸化酶活性在初期4周变化不大,于第5周下降到最低谷,此后又持续上升.随着果实的成熟,3个品种的蔗糖含量升高,淀粉含量呈增加趋势;酸性转化酶活性下降,蔗糖合成酶活性增高.[结论]“红香栗”为淀粉积累型品种,“黄狼”的淀粉和糖类含量都较低,“蜜本”在淀粉和糖类的积累上表现出明显的优越性.在3个品种果实生长前期,其转化酶活性均高于合成酶活性;在果实生长中后期,转化酶活性逐渐下降而合成酶活性上升,于成熟时趋于平衡. |
| 关键词: 南瓜 果实发育 糖代谢 转化酶 蔗糖合成酶 蔗糖磷酸合成酶 淀粉磷酸化酶 |
| DOI： |
| 分类号: |
| 基金项目:河南省科技攻关项目（0624100004） |
|
| Changes of sugar metabolism and related enzyme activities in the development of pumpkin fruit |
|
|
| Abstract: |
| 【Objective】 The study investigated the changes of sugar metabolism and related enzyme activities in the development of pumpkin fruit.【Method】 The changes of nutrient contents,such as fructose,glucose,sucrose,starch,and correlative enzymes activity were studied in Hongxiangli,Huanglang and Miben pumpkin varieties during 1-8 weeks after flowering.【Result】 The fructose and glucose contents of Huanglang and Miben decreased continuously,then increased slightly before harvest,however,the conents of Hongxiangli increased before the third week and then dropped quickly,and the concents of three varieties had little difference in fruit ripening.The neutral invertase activity of Huanglang had a single peak of change,then that of Hongxiangli and Miben had bimodal change.The sucrose phosphate synthase activityof Huanglang and Miben had similar trend of two peaks in the fourth week and sixth week respectively,then reduced gradually after the sixth week.The starch phosphorylase activity of Hongxiangli had obvious bimodal change,appearing in the second week and fourth week,then that of Miben floated 7.6 μg/(g·min) in the former six weeks,and declined rapidly to the lowest point in the seventh week and then went up quickly,however,the content of Huanglang changed little in the first four weeks,and dropped to the lowest valley in the fifth week,then continued to rise.With the fruit ripening of three varieties,sucrose and starch content increase were observed,accompanied by loss of acid invertase activity,and increase of sucrose synthase activity.【Conclusion】 Hongxiangli was the variety which accumulated starch,sugar and starch were low in Huanglang while Miben showed obvious ascendance in accumulation of sugar and starch.The activity of invertase were higher than Sucrose Phosphate Synthase(SPS) and Sucrose Synthase(SS) at the prophase growth of the three varietal fruits, the invertase descended while the SPS and SS ascended at mid and later growth stages, and they got balanced till mature. |
| Key words: pumpkin development of pumpkin fruit sugar metabolism invertase sucrose synthase sucrose phosphate synthase starch phosphorylase |
