Please use this identifier to cite or link to this item:
標題: 細胞分裂素Benzyadenine處理對溫室洋香瓜葉片碳代謝及組織構造之研究
Effects of Benzyladenine on te Carbon Metaboism and Tissue Anatomy of Muskmelon (Cucumis meo L.) Leaves
作者: 蔡燕如
Tsay, Yann-Ru
關鍵字: Musk Melon
Carbon metabilism
出版社: 植物學系
摘要: 溫室洋香瓜果實發育期間,上位葉光合作用速率明顯降低,造成葉片之蔗 糖合成速率亦隨之下降,而無法運送足夠的蔗糖至果實,導致果實無法獲 得足夠的碳源,進而影響果實的生長。因此,本實驗目希望能提高葉片之 光合作用速率,以增加葉片內蔗糖的含量,供應果實足夠的碳源,進而提 高溫室洋香瓜的品質。利用30 ppm BA於授粉後7天處理植株,實驗結果顯 示,BA處理組之葉面積及生物量明顯高於對照組;在組織構造方面,處理 組葉片厚度明顯提高,主要由於BA促進葉肉細胞大量地吸收水分,因而造 成細胞擴大。另外,葉綠體數目亦增加,可能為光合速率提高的原因之一 。其他碳代謝方面,處理組蔗糖磷酸合成?瞗]SPS)活性恆高於對照組, 處理後15天其活性達到最高;而處理後15天乃至果實採收前,其活性逐漸 下降,顯示蔗糖合成速率已降低;此時,處理組蔗糖含量卻明顯增加,暗 示大部份的蔗糖並未送出,而在葉片內逐漸累積;進一步使得果實無法獲 得足夠的蔗糖,降低了果實量的生長。關於分解蔗糖酵素方面,處理組之 中性轉換?磟〝妘v漸提高,六碳糖含量亦隨之增加,以提供葉片繼續生長 時所需的碳源。由以上結果得知,BA處理能夠延遲葉片老化、提高葉片的 光合速率,並且促進蔗糖累積於葉片;但無法提供充分的蔗糖至果實,而 降低了果實之重量。因此,於受粉7天以30 ppm BA處理植株,並無法改善 果實之品質,是否處理時期不當而導致此結果,有待進一步研究。
During the development period of muskmelon, the photo-synthetic rate of the upper leaves decreased apparently. The export of photoassimilates in upper leaves was reduced and un-able transported to the fruit sufficiently, and resulted in the slow growth rate of fruit. Our purpose here is to improve the photo- synthetic rate in order to increase the content of sucrose in leaves, to supply sufficient carbon, and to refine the quality of muskmelon.We used 30 ppm of benzyladenine (BA) to treat the plant that is 7-day after anthesis. The result indicates that both leaf area and biomass of the BA-treated plants are much higher more then the control. Referred to the tissue anatomy, the leaf thickness of the BA-treated plants increases obviously. This is because that BA can promote leaf cells to absorb more water, and as a result, to enlarge the cells. Besides, the number of the chloroplast also increases suggesting an improved photosyn-thetic rate.As for carbon metabolism, the sucrose phosphate synthase (SPS) activity of the BA-treated plant is higher than that of the control. The activity approaches to the maximum on the 15th day after BA-treated, but gradually diminishes until fruit gath-ering indicating that the rate of sucrose synthesis decreases. However, the content of sucrose in the BA-treated leaves in-crease evidently. Our result suggests that sucrose is accumu-lated in the leaves and fails to transport to the fruits. So, the quality of the fruit reduces. As to the aspect of sucrose degra-dation, the activity of the neutral invertase in the BA-treated plant increase and the content of hexose increase consequently. The increased concentration of hexose can provide sufficient carbon source for the leaves to grow.Our conclusion is that plants treated with BA can avoid leaves from senescence. Is can also increase photosynthetic rate of the leaves, and furthermore, promote sucrose accumula-tion in leaves. But it cannot provide abundant sucrose for de-veloping fruit. And the weight of the fruit decreases conse-quently. So, if we treated the plant with 30 ppm of BA 7-days after anthesis, we still cannot refine the quality of fruit. Whether it is a question of the inadequate treating period is still a doubt and needs further research.
Appears in Collections:生命科學系所



Show full item record
TAIR Related Article

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.