The effect of plant growth regulators on hawthorn (Crataegus sp.) in vitro direct regeneration and confirmation of the genetic fidelity

Abstract

In this study, the effects of culture media and plant growth regulators on Crataegus sp. micropropagation were investigated. The treatments for shoot multiplication were benzylaminopurine (BAP) at five concentrations (0, 4.44, 6.66, 8.88 and 11.10 µM) in combination with indol-3-butyric acid (IBA) at four concentrations (0, 1.23, 2.46 and 4.92 µM) with constant 1.44 µM gibberellic acid (GA3) in MS medium. For root induction, IBA was used 0, 1.23, 2.46, 4.92 and 7.38 µM combined with 0, 2.68 and 5.36 µM naphthalene acetic acid (NAA) in 1/2-strength MS medium. Based on results the highest number of shoots/explant (13.5) was obtained in medium fortified with 11.10 µM BAP plus 4.92 µM IBA and the highest shoot length (5.84 cm) was obtained at 6.66 µM BAP plus 4.92 IBA. The highest rooting (55%) was observed in 1/2-strength MS medium containing 1.23 µM IBA with 5.36 µM NAA after four weeks of treatment. This study with highest shoot proliferation rate provided a reliable protocol for in vitro mass propagation of Crataegus sp. The ISSR amplification results demonstrate the genetic uniformity of in vitro propagation system.