RETRACTED ARTICLE: Evaluation of carbon sources as positive selection agents for chrysanthemum (Dendranthema × grandiflorum) transformation

Abstract

Fourteen different carbon sources were evaluated using thin cell layers to determine their suitability as positive selection agents for chrysanthemum (Dendranthema × grandiflorum) transformation. The choice of carbon source is an indispensable factor in the success of organogenic (callogenic, caulogenic, rhizogenic, and to a lesser extent, somatic embryogenic) programmes in in vitro micropropagation of chrysanthemum. Using flow cytometry, histological analyses, and confirmation of flowering normality, the impact of carbon source on the qualitative and quantitative outcome and response of thin cell layers when these were placed onto organogenic media was assessed. Threshold survival levels (TSLs) could not be obtained for sucrose, fructose, or glucose. TSLs together with organ differentiation were, however, obtained for mannose (60–80 g/litre), xylose and lactose (40 g/litre), and cellulose (60–80 g/litre), although abnormal shoot formation was observed in the first of these. Xylose, lactose, and cellulose can consequently be considered potential carbon sources for positive selection systems in chrysanthemum genetic transformation.