Author
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Hammerschlag, Freddi |
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Smigocki, Anna |
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Submitted to: Plant Cell Reports
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/6/1998 Publication Date: N/A Citation: N/A Interpretive Summary: An important goal in peach breeding is to produce compact peach trees, however, long generation time and a narrow germplasm base have impeded progress in the genetic improvement of peach. Gene transfer studies have demonstrated that the bacterial cytokinin biosynthesis gene ipt can alter the growth habit of a number of plants. In this study, we report on the growth and development of three independent ipt transformants grown in vitro and in the greenhouse. This study should be of value to fruit tree biotechnologists and plant breeders who are interested in generating fruit trees with a compact growth habit. Technical Abstract: Peach plants, transformed with a cytokinin biosynthesis (ipt) gene were evaluated for altered growth habit. After nine weeks of in vitro propagation on four different levels of 6- benzyladenine (BA), the average number of axillary shoots per plant for two independent transformants, 99-1 and 40-1, were up to 2.6 times that for the controls on 0-30 uM of BA, whereas average fresh weights were up to 10 times that for the controls. Tolerance of a supra-optimal (30 uM) concentration of BA was observed in at least 50% of 99-1 and 40-1 shoot cultures. Greenhouse-grown transgenic plants were on the average 10-44% shorter than controls at six weeks and at one year. Amount of branching on 94-1 and 99-1 was not significantly different from controls, whereas that for 40-1 was almost twice that of controls when scored at six weeks and one year. |
