芋葉大小與形状之生長型式量化分析及季節性變異

Seasonal Variation and Quantitative Analysis of Growth Patterns in Size and Shape for Taro Leaves

吕秀英(Hsiu-Ying Lu) ； 魏夢麗(Meng-Li Wei) ； 吕椿棠(Chun-Tang Lu) ； 陳烈夫(Lit-Fu Chan)

《中華農業研究》 51卷2期 (2002/06) Pp. 32-49

https://doi.org/10.29951/JARC.200206.0004

摘要

確實掌握芋葉在生長過程中的動態變化，可预测芋的球莖產量生產。葉片之生長發育受到外界環境影響甚钜；而葉片表面伸展速率的不同，不但造成葉片大小之變化，其形状也可能有所差異。本研究主要目的在探討本省芋作物在不同葉位的葉片大小舆形状在生是遇程中的變化，及其在不同期作栽培下受氧候因素之影響差異。試驗材料與本省地方品種檳榔心芋及其選育品種「高雄一號」，在農業試驗所進行兩年兩期作之栽培試驗，在水芋的全生育期間以非破壞取樣之方式，將所有葉片自初生展開日起依植株生長發育之速率每隔2~4天，利用影像處理系統數位相機予以照相存檔，直至枯萎老化為止，然後在電腦上進行葉片大小及形狀的數量化處理，收穫時則調查植株各部位鮮、乾重。結果得知，芋葉特徵變異可以兩個主成份來適當描述：第一主成份包含面積和所有長寬度量之與葉片大小有關的性狀，第二主成份則由6個指標綜合構成芋葉形狀。決定了葉裂凹點、葉柄銜接點、兩葉基尖端各至葉尖的相對位置，和兩葉基弧長的轉折點，再加上葉裂角度，應該足以描述及掌握芋葉的形狀特徵。芋葉在初生展開時顯得較狹長、葉裂較深、葉裂角度較小，但隨後葉形便趨於一致。芋葉的兩個葉基並不對稱，高雄一號的右葉基稍大於左葉基，而檳榔心芋則是左大於右。由於兩期作間生長階段氣候變化不同，一月種植期在地上部生長旺盛期的高溫強日照，葉片伸展較快，此有利於收穫時之球莖產量；而七月種植期在地上部生長旺盛期逢低溫寡日照，葉片伸展較慢，故產量較低。葉裂角度、葉裂凹點至葉柄銜接點之長對最大葉長之比例的生長型式受氣候差異之影響在不同期作間有明顯差異。高雄一號在一月種植期的葉裂凹點至葉柄銜接點之長度的延伸較七月種植期及檳榔心芋為快，故造成葉面積上的優勢，致球莖產量提高。

關鍵字

芋 ； 葉片大小 ； 葉形 ； 主成份分析 ； 影像處理系統 ； 氣象因素

並列摘要

Productivity of corm is determined by the adequate growth of leaves in taro (Colocasia esculenta [L.] Schott). The development and growth of leaves vary with the environmental factors. The difference in rates of expansion of leaf surface can lead to the variation in leaf size and leaf shape. This study was to investigate the morphological changes occur in the taro leaves and examine the influence of climatic factors on the leaf size and leaf shape of taro during the growth periods. Binroshin taro and its improved cultivar ”Kaohsiung No.1” were used as materials. The experiments were conducted in two crop seasons at Taiwan Agricultural Research Institute. After leaf expanding, measurements were made every 2-4 days depending on the speed of plant development, until leaf is senescetst and die. We used digit camera to capture images of the individual leaves and then used image measurement software to determine the image quantification. At harvest, fresh and dry matter weights for different fractions of each taro plant were measured. The principal components analysis showed the first component summarized size variation, while the second contrasted shapes. The shape component was determined by six indices together. Leaf shape of taro was appropriately described by determining the relative positions of the sinus base, the petiole-attaching point of leaf, the lobe tips to the apex, respectively, and the turning points of two lobe tips as well as the angle of sinus. The juvenile leaves were frequently narrower, longer and more lobed, but similar in their shape forms to mature leaves. The cultivar ”Kaohsiung No.1” had the greater right lobe, while Binroshin taro had the greater left lobe. Climatic factors influenced the leaf growth of taro. Rising temperature and higher solar radiation during the vigorous top-growth stage for January crop increased the rate of leaf expansion. This favored corm yield at maturity for January crop. On the other hand, declining temperature and lower solar radiation during the vigorous top-growth stage for July crop decreased the rate of leaf expansion. This resulted in poor yield at maturity. Planting times affected the growth patterns of the angle of sinus, and the ratio of length from the sinus base to the petiole-attaching point of leaf to maximum leaf length. The cultivar ”Kaohsiung No. 1” grown in January had more rapid expansion in the ratio of length from the sinus base to the petiole-attaching point of leaf to maximum leaf length than that for the July crop and Binroshin taro. This resulted in greater leaf area, which in turn, favored corm yield at maturity.

並列關鍵字

Taro ； Leaf size ； Leaf shape ； Principal components analysis ； Image processing system ； Climatic factor