Acta Agriculturae Serbica (Jan 2020)
In vitro propagation and medium-term conservation of autochthonous plum cultivar 'Crvena Ranka'
Abstract
In vitro strategies for the propagation and conservation of indigenous species contribute to the sustainable use of plant diversity and are essential for breeding programs as well. In this study, we established an efficient protocol for the micropropagation of autochthonous plum 'Crvena Ranka' and examined the survival and regrowth capacity of in vitro shoots after 3, 6 and 9 months of cold storage (CS) at +5 oC in total darkness. Aseptic culture was established on the Murashige and Skoog medium containing 2 mg l-1 BA, 0.5 mg l-1 IBA and 0.1 mg l-1 GA3 (leaf rosette initiation being 68.8%). During in vitro propagation on the medium of constant hormonal composition, a significant increase in the multiplication index was observed in the third subculture, whereupon it was mainly stable until the fifth subculture. The effect of BA concentration and/or type of auxins (IBA or NAA) on multiplication parameters, as well as on fresh and dry weights of shoots was evaluated. BA at 1 mg l-1 in combination with NAA significantly increased shoot multiplication parameters. The effect of auxins on rooting parameters was monitored as well. Shoots cultured on the medium supplemented with NAA also displayed higher rooting ability (60%), in comparison with those grown on the medium containing IBA at the same concentration (20%). In vitro shoots can be conserved over the medium term under CS conditions up to six months. High survival was achieved after three (94%) and six months (82.5%), while severe signs of necrosis (100%) were noticed after nine months of conservation. Shoots subcultured under standard growth conditions after CS promptly regained their morphology although their capacity for multiplication and rooting was slightly lower than that of non-cold-stored shoots.
