Leaf color stability during plant development as an index of leaf color variation among micropropagated Caladium

Abstract

The developmental pattern of leaf color distribution during plant development in 10 cultivars of Caladium xhortulanum Birdsey was investigated. We used the color occupying the largest area in the terminal leaf as the dominant color, and expressed the leaf color stability during plant development by the ratio of the percentage of the dominant color area in the terminal leaf to that of the dominant color area in the initial leaf (leaf color stability index). In some cultivars, leaf color stability index was clearly greater than 1 (leaf-color-unstable cultivar), but in some cultivars it was close to 1 (leaf-color-stable cultivar). In plants regenerated from leaf explants of leaf-color-unstable cultivars, many (21 % to 43 %) color variants were observed but only a few (0 % to 6 %) occurred from leaf explants of leaf-color-stable cultivars. Tissue culture appears to be a useful technique for rapid propagation based on leaf color stability in leaf-color-stable and leaf-color-unstable cultivars.