Somatic embryogenesis and transformation of the diploid Rosa chinensis cv Old Blush

Abstract

International audienceSomatic embryogenesis was induced from in vitro-derived leaf explants of Rosa chinensis cultivar (cv) Old Blush. Calli producing embryos with expanded cotyledons (RcOBType1 embryos) were obtained. Further refinements of the callus maintenance medium generated a more typical rose embryogenic callus (RcOBType2) displaying high levels of secondary embryogenesis and embryos with limited cotyledon expansion Agrobacterium tumefaciens-mediated transformation assays using β-glucuronidase (GUS) reporter gene showed that both types of embryos were competent for transformation. Under selection conditions, transformed RcOBType1 explants produced non chimaeric transformed embryos, from which shoots could be adventitiously regenerated. In contrast to RcOBType1, transformed RcOBType2 embryos directly yielded transformed shoots when repeatedly cultured in selective regeneration conditions. Transformation efficiency ranged between three to nine percent and shoots suitable for rooting were obtained within 6-8 months. Transgenic plants were transferred into the greenhouse and molecularly confirmed. The availability of transformation methods in a diploid rose, R. chinensis cv. Old Blush, will be useful for gene functional studies

Efficient Agrobacterium-mediated transformation of Pennisetum glaucum (L.) R. Br. using shoot apices as explant source

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DREB1C from Medicago truncatula enhances freezing tolerance in transgenic M. truncatula and China Rose (Rosa chinensis Jacq.)

“…Use of alternative plant growth regulators, such as zeatin (Vergne et al 2009) to produce more transgenic China Rose lines, and using higher concentrations of cefotaxime to avoid contamination by Agrobacterium, will be assayed. The function of downstream genes controlled by MtDREB1C associated with freezing stress tolerance in the transgenic China Rose should also be further studied.…”

Transgenics in Ornamental Crops:Creating Novelties in Economically Important Cut Flowers

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