An interspecific somatic hybrid between Actinidia chinensis and Actinidia kolomikta and its chilling tolerance

Abstract

Protoplasts isolated from cotyledon-derived callus of Actinidia chinensis Planch. var. chinensis (2N ¼ 2x ¼ 58) were fused with mesophyll protoplasts of Actiniadia kolomikta (Maxim. et Rupr.) Maxim (2N ¼ 2x ¼ 58) using a PEG method. Plantlets were regenerated from the fusion product clone 11. RAPD analyses, chromosome numbers of root tip cells and fluorescence peak position of leaf nuclei confirmed that clone 11 was an interspecific somatic hybrid (2N ¼ 4x ¼ 116) between A. chinensis and A. kolomikta. The chilling tolerance of the somatic hybrid was tested with in vitro leaves at low temperatures. Based on data of leaf thickness, electroconductivity, proline levels, malondialdehyde content and activity of superoxide dismutase, dendrogram cluster analysis suggested that the interspecific somatic hybrid was similar to A. kolomikta, and might have a higher capacity of cold resistance than A. chinensis.

Distribution, Ploidy Levels, and Fruit Characteristics of Three <i>Actinidia</i> Species Native to Hokkaido, Japan

“…Actinidia arguta has cross compatibility with hexaploid kiwifruit (A. deliciosa), and several hybrid cultivars have been produced recently . As for A. kolomikta, several hybrid plants with kiwifruit (A. deliciosa and A. chinensis) have also been obtained recently by embryo rescue or protoplast fusion (Hirsch et al, 2001;Xiao et al, 2004). Xiao et al (2004) reported that the interspecific somatic hybrids between A. kolomikta and A. chinensis obtained by protoplast 112 fusion had potential cold tolerance.…”

“…As for A. kolomikta, several hybrid plants with kiwifruit (A. deliciosa and A. chinensis) have also been obtained recently by embryo rescue or protoplast fusion (Hirsch et al, 2001;Xiao et al, 2004). Xiao et al (2004) reported that the interspecific somatic hybrids between A. kolomikta and A. chinensis obtained by protoplast 112 fusion had potential cold tolerance. Another interesting approach is to use elite accessions themselves for further improvement, by the approach such as polyploidization, genetic transformation, and mutagenesis.…”

Application of somatic hybridization for the improvement of horticultural crops

“…Besides the application of SH mentioned above, other agriculturally important traits modified by SH include chilling tolerance in Actinidia (Xiao et al, 2004), photoperiodical response in Gossypium (Sun et al, 2005), storage root formation in Ipomoea (Yang et al, 2009) and creation of new genome/cytoplasm combinations for generating CMS (Cai et al, 2006). (Fitter et al, 2005) demonstrated the possibility of introgressing CMS by mtDNA from a wild species.…”

Applications of Biotechnology in Kiwifruit (Actinidia)

“…Isolated protoplasts from cotyledon-derived calli for A. chinensis (2n = 2x = 58) and A. deliciosa (2n = 6x = 174) were fused, using a PEG (polyethylene glycol) method and plantlets were regenerated from the fused calli. Xiao et al (2004), in an attempt to introduce the chilling tolerance characteristics of A. kolomikta into A. chinensis, fused protoplasts isolated from cotyledon-derived calli of A. chinensis (2n = 2x = 58) and the mesophyll cells of A. kolomikta (2n = 2x = 58). A number of techniques were employed to confirm that the regenerated plantlets were an inter-specific somatic hybrid (2n = 4x = 116) and assessment of the chilling tolerance of in vitro leaves suggested that the somatic hybrid was more similar to A. kolomikta, with a higher capacity of cold resistance than A. chinensis.…”