Studies on Matter Production of Edible Canna (Canna edulis Ker.) : III. Changes of production structure with growth

[摘要] Edible canna is a highly productive crop in temperate to tropical regions. To clarify ontogenetic changes of structure which contribute to its high yield capacity, edible canna was grown from late April to mid-November in 1-m rows with spacing of 0.5 m between plants in the row at the experimental field of the University of Tsukuba. During the growth period, light transmittance into the canopy was measured and the aerial allocatons of dry weight and leaf area were determined by stratified clipping. The plants reached maximum height by mid-September, at which time the leaf area index (LAI) exceeded 10 and reached a maximun of 11.2 before declining as the plant matured. The light extinction coefficient (K) changed from 1.34 (typical of broad-leaf plants) in early growth to 0.4-0.5 (typical of grasses) in the latter growth stages. This indicated that in the early growth, this crop developed planophyll leaves which maximized light interception under low LAI but with growth, the upper leaves became more upright, which enabled light to penetrate deep into the tall canopy. The initiation of shoots and the azimuth angles of leaves as the plants grew appeared to be such that light interception by the crop canopy was maximized.

[学科分类] 农业科学（综合）

[关键词] Canna edulis Ker.;Dry matter production;乾物生産;Edible canna;吸光係数;Growth;食用カンナ;Leaf area;生産構造;Leaf inclination;生長;Light extinction coefficient;葉身角度;Production structure;葉面積