Effect of Brassinolide ,Cytokinin and Auxins on In Vitro propagation of Citrus Rootstock ( Troyer Citrang )

Abstract

A study on in vitro micropropagation of a citrus Rootstock Troyer Citrange Was Conducted at the tissue culture lab.located in postgraduate building /Collage of Agric./Uni.of Baghdad from September 2010 till August 2011. Single nodal segment or terminal shoots were explanted on MS medium supplemented with different concentrations of plant growth regulators( Brassinolide ,Cytokinin and Auxins ). The aims of the study were increasing number and length of shoots , rooting and plantlet acclimatization . Results showed that 3% of NaOCl was the best for explant disinfestation only 25% of explants were contaminated .Although 4.5 or6.0 %of NaOCl gave 100% disinfestation ،the concentrations were poisonous. Single nodal segments responded better than terminal shoots. In the establishment stage. MS medium supplemented with 1.0 mg / L BA + 0.2mg / L IAA was superior on shoot multiplication ( 5.30 shoots / explant) . While MS medium supplemented with 1.0 mg / L NAA + 0.096 mg / L BL. was more effective on root number 4.89 roots / explant .Most plantlets 90% were acclimatized when cultured on soil consisted of 1 : 1 sand : peatmoss.*Part of M. Sc.thesis of the second author