Regeneration via direct organogenesis from leaf and petiole segments of pyrethrum [Tanacetum cinerariifolium (Trevir.) Schultz-Bip.].

Abstract: A highly reproducible in vitro regeneration system in pyrethrum has been developed. Multiple shoots were induced in vitro from leaf and petiole explants through adventitious shoot bud regeneration. The ability of leaf segments to produce direct shoot buds varied depending upon their medium composition. Leaf segments were highly responsive than petiole cuttings and produced a maximum shoot regeneration (70%) on MS medium supplemented with 4 mg l BA and 0.2 mg l 2,4-D. The highest proliferation rate was observed1 1 on MS medium supplemented with 1.5 mg l BA and 2 mg l NAA. The highest means of shoot length were1 1 produced in all media without BA and using BA in culture media resulted in production of short shoots. The highest fresh weight of shoot was observed on MS medium when compared to B5 and SH. For rooting of the shoots, MS, B5 and SH medium supplemented with different concentrations of (alpha)-naphthalene acetic acid (NAA) were tried. The optimal result was observed on B5 medium supplemented with 2 mg l NAA, on1 which 100 % of the regenerated shoots developed roots with an average of 16 roots per shoot within 3 weeks. The in vitro raised plantlets were acclimatized and transferred to greenhouse with 80 % success. Key words:6-benzylaminopurine Leaf explants Petiole cuttings Organogenesis Tanacetum cinerariaefolium INTRODUCTION other warm blooded animals [3]. The vegetative