In vitro selection for Fusarium oxysporum f. sp. conglutinans resistance in brassica vegetables

Abstract

<p class="abstract"><strong>Background:</strong> Fusarium wilt is an issue of concern in economically and nutritionally important Brassica vegetable cultivation. Thus, it deserves measures against the adverse production impact caused by Fusarium wilt.</p><p class="abstract"><strong>Methods:</strong> In this study, development of resistance to <em>F. oxysporum</em> f. sp. <em>conglutinans</em> in six white head cabbage cultivars, by in vitro chemical mutagenesis and selection, through direct and indirect organogenesis was examined. 6 day and 10 day old hypocotyl, shoot tip and calli, from 6 day old hypocotyl explants, were subjected to chemical mutagenesis treatment (DMSO (4% v/v) + EMS (0.3% v/v) for two hours at 28±2°C) were incubated in MS shoot induction medium (MS+ NAA (0.2 mg/l), BAP (3 mg/l), GA3 (0.01 mg/L) and AgNO3 (0.5 mg/l)). Shoots developed from hypocotyl and shoot tip explants (in the MS shoot induction medium and then in MS + NAA (0.2 mg/l), BAP (3 mg/l), GA3 (0.01 mg/l) for shoot development) and calli following mutagenesis treatment were screened for Fusarium resistance subjecting to 15% and 20% <em>Fusarium</em> culture filtrate for 30 and 60 day selection periods for each strength respectively.  </p><p class="abstract"><strong>Results:</strong> Developed plantlets from all six cultivars tested, showed resistance to<em> </em>Fusarium culture filtrate in the in vitro conditions with different survival frequencies ranging between 12.5% to 84.0% from hypocotyl and 0.0% to 86.7% from shoot tip explants among cultivars indicating development of resistance to <em>Fusarium</em> by in vitro chemical mutagenesis.</p><p class="abstract"><strong>Conclusions:</strong> Direct organogenesis, and 10 day old hypocotyl and 6 day old shoot tips are potential explants for successful application of in vitro chemical mutagenesis for Fusarrium resistance development in in cabbage.</p><p class="abstract"> </p>