同化物分配及其對果實品質之影響
Other Title
ASSIMILATE PARTITIONING AND ITS EFFECTS ON YIELD AND QULITY IN FRUIT CROPS
Journal
果樹營養與果園土壤管理研討會專集
Pages
23-28
Date Issued
1989-04
Author(s)
顏昌瑞
Karen E. Koch
Chung-Ruey Yen
Karen E. Koch
Abstract
同化物之分配對果樹產量及果實品質有極顯著之影響，同化物(assimilates)之來源主要爲光合作用及暗固定，其產生部位、代謝途徑，及分配均不相同。
葉片光合產物傳送至果質爲影響果實產量及品質之主要因素，果實暗固定則與有機酸之代謝有關。葉片光合產(photosynthetes)分 配途徑依次爲：於藥片經由光合作用產生，以sucrose 等非選原糖於葉片篩管組織装載(loading)，經篩管長程運輸，於積存細胞(sink)卸載(unloading)，並代謝成醣及酸，貯於液胞。葉之光及暗固定同化物主要運送至果實之內部，果實之光合作用產物主要仍保留在果皮，果實之暗固定同化物則大致平均分佈於果實各部位。葉片光合作用爲果實生長所需碳之最主要來源。葉片光合產物常傳送至果實之相對部位，因此，葉片數目及位置對果實品質有顯著之影響，而且決定果實生理病害之發生率。
果實暗固定爲呼吸作用排出二氧化碳之再固定，其同化物多於其產生部位代謝，較少運至其他組織。果實發育初期之有機酸主要來自葉片，但隨著果質之發育，暗固定同化物逐漸成爲主要有機酸來源之一。砷酸鹽(Arsenate)處理滅少柑橘有機酸主要在於其對葉片同化物之分佈之影響，處理植株之葉片運送較多之光合作用產物至果寶。利用園藝方法以改變source-sink關係包括：1.蔬果，2.除新梢，3.斷根，4.嫁接，5.施用生長素，6.整枝修剪等，均加以說明。
Patterns of assinilate partitioning can affect yield and quality significantly, In the present study, assimilate source, metabolism, and distribution differed depending on whether initial CO2 was taken up in light or darkness.
In grapefruit, 14CO2 assimilated by leaves in either light or darkness gave rise to radiolabel later recovered in fruit, particularly the juice sacs. In contrast, 14CO taken up during photosynthesis by fruit resulted in deposition of radiolabel in flavedo and albedo, where it remained for an extended period Dark fixation of 14CO2 by fruit, however, brought about an even distribution of label among fruit tissues. Assimilates derived from leaf photosynthesis were the primary carbohydrate source for the fruit. Most leaf photosynthates were deposited in aligned fruit parts, a process that could significantly affect soluble solids distribution in fruit. Leaf number and point of attachment may thus influence fruit quality. The decrease in acidity of grapefruit by arsenate treatment appears to involve altered partitioning and/or translocation of photosynthates from leaves.
Assimilation of CO2 in the dark, typically resulting in organic acid synthesis via refixation of repository CO2, appeared to contribute increasing amounts of acid to juice sacs as fruit size increased.
Horticultural practices to improve yield and quality of fruit crops are discussed.
Event(s)
果樹營養與果園土壤管理研討會
Proceedings of a Symposium on Fruit Tree Nutrition and Orchard Soil Management
Publisher
台中區農業改良場
Type
conference paper