反季节龙眼不同发育时期果实脱落响应差异与果实呼吸耗氧量的关系  

Relationship between Fruit Abscission Response and Respiratory Oxygen Consumption Rate during Different Fruit Developmental Stages of Off-season Longan

作　　者：杨子琴[1] 李松刚[1] 张蕾[1] 何书强 洪继旺 YANG Ziqin;LI Songgang;ZHANG Lei;HE Shuqiang;HONG Jiwang(Tropical Crops Genetic Resources Institute,Chinese Academy of Tropical Agricultural Sciences/National Center for Tropical Fruit Tree Varieties Improvement,Haikou,Hainan 571101,China)

机构地区：[1]中国热带农业科学院热带作物品种资源研究所/国家热带果树品种改良中心,海南海口571101

出　　处：《热带作物学报》2024年第9期1851-1856,共6页Chinese Journal of Tropical Crops

基　　金：海南省自然科学基金项目(No.323RC535);国家自然科学基金项目(No.32472693);国家荔枝龙眼产业技术体系项目(No.CARS-32-21)。

摘　　要：反季节龙眼在果实发育过程中落果现象非常严重。前期的研究表明,果实中碳水化合物水平的下降与果实脱落密切相关。为了进一步了解不同发育时期果实的碳水化合物代谢变化与脱落差异的关系,以反季节储良龙眼为试材,果穗从树上剪下后迅速插入清水中并去除叶片诱发果实脱落,通过测定胁迫处理下3个发育时期果实落果率、呼吸耗氧量、果柄分离力变化,检测不同光强对3个时期果实呼吸的影响,发现不同发育时期龙眼果实对脱落的敏感性不同。饥饿胁迫迅速启动了各发育时期果实的脱落响应,但3个时期果实脱落响应差异较大,幼果期果实对饥饿胁迫的响应较中期和后期延后2 d,果实发育中期和后期脱落响应更剧烈;幼果期果实呼吸耗氧量较低,而果实发育中期和后期呼吸耗氧量较高;随着光强的增加,仅幼果期果实呼吸作用未造成氧气的下降,还出现了氧气的释放。幼果期果柄分离力下降也较果实发育中期和后期缓慢。因此,本研究结果表明,在胁迫条件下果实呼吸作用与果实脱落密切相关,果实呼吸强度越强;在饥饿胁迫条件下果柄分离力下降越快,果实脱落越快。龙眼幼果期可通过果皮进行光合作用部分代偿呼吸对碳水化合物的消耗。幼果期饥饿胁迫下落果慢的主要原因是低的呼吸消耗和具有一定的光合能力,因此,龙眼幼果是一个部分自养的器官。Fruit abscission in off-season longan is very serious during fruit development in Hainan,China,and severely affectse the formation of production.However,the research on the regulation of longan fruit abscission mainly is focused on fruit thinning,and there are very few studies on fruit preservation.The mechanism of abscission is mainly focused on hydrolase genes and reactive oxygen species,there is no report of fruit respiration on carbohydrate metabolism affecting fruit abscission.Previous studies showed that the decrease in carbohydrate level in fruit was closely related to fruit abscission.In order to further understand the relationship of carbohydrate metabolism and abscission,fruit clusters of off-season Chuliang longan were detached from tree body,the peduncles were immediately inserted into pure water and defoliation treatmented after detachment,which caused starvation stress and induced fruit abscission.Therefore,detachment of the fruit clusters from the tree served as starvation stress treatment.Change in the fruit abscission 1852热带作物学报第45卷rate in the starvation stressed fruit clusters,respiratory oxygen consumption rate and fruit removal force in the three developmental stages under detachment were examined,and the effects of different light intensity on fruit respiration in the three stages were analyzed.It was found that longan fruit at different developmental stages differed in sensitivity to starvation stress,which rapidly initiated the fruit abscission response in all the three stages,but there were large differences in speed of fruit shedding.Young fruits responded to starvation stress for two days later than those in the middle and the late fruit development stage would lead to more intense fruit abscission response in the middle and the late stages.Respiratory oxygen consumption rate was the lowest in the young fruit stage.With the increase of light intensity,the respiration of young fruits did not cause a decrease in oxygen,but rather a release of oxygen.The decrease in the frui

关 键 词：龙眼 胁迫 果实脱落 呼吸耗氧量 果柄分离力 

分 类 号：S667.1[农业科学—果树学]