頁籤選單縮合
題 名 | 植物分析與施肥 (2)--影響樹葉片中大量營養素濃度因子研究=Plant Testing (2) : Factors Affecting the macro-Nutrients Concentration of Tea Leaves |
---|---|
作 者 | 林家棻; | 書刊名 | 中華農學會報 |
卷 期 | 53 民55.03 |
頁 次 | 頁42-49 |
關鍵詞 | 植物葉片; 施肥; 營養素濃度; |
語 文 | 中文(Chinese) |
中文摘要 | 葉片中無機營養素的濃度可反映其他部位要素的供應情形以及整株植物的基本生理作用。因此利用植物分析探討施肥問題時,多以葉片為採樣對象,但由於葉片的敏感性,其所含無機營養素的濃度可受許多因子的影響。為使採樣技術的標準化,必須先明瞭可影響葉片營養素濃度的因子,藉可獲得可資相互比較之代表性樣本。 本文乃討論可影響茶樹葉片中大量營養素濃度的因子,其結果摘要如下: (一)若以每欉茶樹採取葉片二枚,其採取量已茶欉總數15%為宜。所採取之葉片必須發育程度相等,外形大小一致者。全日中葉氮濃度以午間最高,晨昏較低,採樣工作最好能在午前完成。 (二)就不同部位葉片中氮磷鉀濃度而言,以葉齡愈輕者濃度愈高,就季節而言,各部位葉片中營養素濃度以春秋較高,夏季較低。又葉齡愈輕者,受季節之變異愈大,成熟葉中磷鉀濃度幾不受季節的影響。 (三)不同品種間,葉片中營養素濃度變異甚大,其中尤以葉氮為然。 (四) 茶樹經不同深度修剪之後,萌發枝條上的葉片中營養素濃度隨剪枝深度而提高,且極顯著。 (五)遮蔭亦可影響葉片中之氮濃度。 |
英文摘要 | Leaves may be regarded not only as the seat of carbon assimilation by plants, but also as a portion of the mineral storage reservoir of the plant which reflects the level of supply in the other tissues. It is, therefore, the tissue commonly used for analysis is the leaf. However, the mineral composition of leaves is readily subject to change by many factors including genetic and environments. This paper deals with factors affecting the macro-nutrient concentrations of tea leaves in order to minimize the errors involved in leaf sampling for diagnostic purpose. Its results may be summerized as follows: 1. Leaves of similar maturity and size in appearance should be sampled. If two leaves were selected for each tree, it was found that leaf sample taken from 15 per cent of trees surveyed was able to minize sampling error as indicated by the coefficient of variation. For avoiding diural variation in leaf nitrogen, samples should be taken before noon, especially in sampling the third yound leaves. 2. It was found that the concentrations of nitrogen, phosphorus, and potassium tended to decrease with the age of leaf. Important differences in the seasonal change of NPK-concentration in tea leaves from different positions upon the plant were found. Generally speaking, the nutrient concentration in leaves tended to increase in spring and fall and to decrease in summer. It was especially prominent in the samples taken from bud and tender leaves, but only slight change was found in the matured leaves throughout the season. 3. Significant differences in leaf composition among tea varieties which are commonly planted in Taiwan were also found. 4. For regenerating the growth of tea plant, several kinds of prunning, i.e., collar prunning, heavy prunning, medium prunning and light prunning are usually practiced in tea culture. It was found that the concentrations of leaf-nutrient were proportionately to the degree of prunning, in other words, the heavier the prunning practiced, the higher the concentrations of leaf-nutrient would be. 5. In the tea plantation of Taiwan, a legume, Acacia confusa, are commonly interplanted with tea plant for the purpose of windbreak and shading effect. It was found that leaf-N content was greatly affected by shading. |
本系統中英文摘要資訊取自各篇刊載內容。