蓮霧園管理因子與裂果發生之關係

Relationships between Various Orchard Management Factors and Fruit Splitting in Wax Apples

裂果是蓮霧（Syzygium samarangense Merr. et Perry）最常發生的生理劣變之一。本研究以問卷調查方式，分析臺灣蓮霧產地之果園管理因子與裂果發生之關係，結果顯示‘大果’蓮霧裂果率較‘粉紅’蓮霧為高。在不同季節生產之果實，夏果裂果率最高，其次為春果和秋果，冬果為最低。樹齡年輕者較易發生裂果。植株樹勢強者裂果率亦較高。嫁接植株之裂果率明顯高於高壓及扦插植株。草生栽培者裂果率較清耕者低。種植於石礫地者其裂果率較其他土壤質地者高。土壤水分灌溉量高者其裂果率亦較高。在催花前經適當的修剪、浸水及遮光處理者，裂果率較低。果實成熟時大量抽新梢者，其裂果率較高。著生於樹冠內部之果實其裂果率低於著生於樹冠外圍之果實。果實鮮重與裂果率呈正相關。 Fruit splitting is one of the most common physiological disorders in wax apples. A survey was conducted in the major wax apple production area in Taiwan in order to understand the relationships between various orchard management factors and fruit splitting. The results indicated that many factors could affect the incidence of fruit splitting. 'Big-fruit' cultivar prevailed over 'Pink' cultivar in fruit splitting. Summer fruit had the highest incidence of fruit splitting, followed by spring fruit, autumn fruit and winter fruit. Young trees produced higher percentages of split fruit than older trees. Fruit splitting was more severe in vigorous trees than in weaker ones. Gravel soils produced higher percentages of fruit with splits than loamy or clayey soils. Sod culture reduced fruit splitting compared to clean cultivation. Grafted trees produced higher percentages of split fruit than trees propagated by air-layering or cutting. Excessive irrigation increased fruit splitting. Mild pruning, flooding or shading before flower forcing reduced fruit splitting. Massive vegetative flushing during fruit maturation stage aggravated fruit splitting. Splitting occurred more frequently in fruit set in inner canopy than in outer canopy. There was a positive relationship between the fresh weight of the fruit and splitting.