Cell lines and plants obtained after protoplast fusions of Rosa+Rosa, Rosa+Prunus and Rosa+Rubus

Abstract

Protoplasts of three Rosa cultivars were fused with each other, with protoplasts of Prunus 'Colt' and with protoplasts of Rubus laciniatus, using polyethylene glycol 4000 as a fusogen. Protoplasts of Prunus were incapable of cell division and those of Rosa and Rubus were disabled by treatments with metabolic inhibitors, either iodoacetate (IOA) or rhodamine 6-G (R6G). Parental protoplasts were then fused in combinations that required complementation for their survival. RAPD analysis of 41 fusion-derived cell lines showed that two lines resulting from fusions of Rosa+Rosa and one from a fusion of Rosa+Prunus, contained some DNA markers from both fusion partners. The others contained markers of only one fusion parent. This showed that after protoplast fusion, the heterokaryons did not develop into cell lines with stable hybrid nuclei. Plants regenerated from cell lines derived from Rosa+Prunus and Rosa+Rubus fusions contained DNA markers of only Rosa and their DNA amounts were no greater than that of the Rosa parent. However, they differed morphologically from the Rosa parent to a remarkable degree, possibly because they inherited undetected genes of Prunus or Rubus, or because they were somaclonal variants of the Rosa parent. Alternative strategies for the production of somatic hybrids are discussed.

Rosa

“…Increasing vigor, introducing fungal resistance, and improving fertility were the aims of Mottley et al (1996) and Squirrell et al (2005) in their attempts to produce hybrids from intergeneric fusions of three rose cultivars with a cherry rootstock Prunus avium  pseudocerasus "Colt" or a blackberry Rubus laciniatus "Thornless Oregon." They also performed selffusion with a wild rose hybrid, Rosa persica  xanthina to increase the ploidy level to tetraploid.…”

Regeneration of somatic hybrids of ginger via chemical protoplast fusion

“…Identification of the regenerated plants RAPD has been employed efficiently to characterize somatic hybrids derived from symmetric somatic hybridization (Xia et al 2003;Squirrell et al 2005). Twelve primers were used to identify the regenerated plants and one of these (primer S510 CCATTCCCCA) are shown in Fig.…”

Effect of Culture Media and Plant Growth Regulators on Shoot Proliferation and Rooting of Internode Explants from Moroccan Native Almond (Prunus dulcis Mill.) Genotypes

“…In vitro propagation is an alternative to overcome this kind of problem. Since tissue culture technology has been widely used for a large-scale micropropagation of commercial plants [20,21], germplasm protection [22], and development of new hybrids [23], it can provide clean planting materials (virus and diseases-free) for new orchards avoiding economic losses [24][25][26]. Prunus species was successfully reproduced for the first time in the 1960s [27], and most research on this species was focused on the optimization of reproduction steps by using leaves explants [28], axillary buds [29], seed [30], or branch tips [20].…”