Authors: Yafeng Zhang Jiehong Zhou Tao Wu Jiashu Cao
Publish Date: 2008/04/22
Volume: 93, Issue: 3, Pages: 323-
Abstract
To induce multiple shoots from pumpkin Cucurbita moschata Duch cotyledon explants excised from various ages of seedlings after in vitro germination were cultured on MS augmented with different concentrations of BA 0 05 10 or 20 mg l−1 The highest frequency of shoot regeneration 637 was observed from sevendayold cotyledon explants cultured on MS containing 05 mg l−1 BA The frequency and duration of shoot formation showed close correlation with the donor seedling age By contrast BA supply was necessary to promote shoot formation but no differences were observed in relation to different concentrations Multiple shoots elongated on MS supplemented with 01 mg l−1 BA and 5–7 shoots per regenerated explant were recovered Elongated shoots were rooted on MS which was easier than that on 2/3MS 1/2MS or MS supplemented with 01 mg l−1 NAA The rooted shoots were then transferred to greenhouse where they grew and flowered normally Quantitative analysis of endogenous auxin IAA and cytokinins iPA and ZR in initial cotyledon explants of different aged seedlings showed that the regeneration ability of cotyledon explants varied dependently on their endogenous iPA contents This study therefore deduces that the various organogenic capabilities of cotyledon explants from pumpkin are the result of their endogenous hormonal contents
Keywords: