Abstract

IN – VITRO PRODUCTION OF PYRETHRINS FROM RAY FLORETS OF TAGETES ERECTA L.

*Sushma Laxman Nikam and Shahana Jafar Khan

ABSTRACT

Tagetes erecta is a common ornamental plant that belongs to family Asteraceae, in which pyrethrins the economically most important natural insecticide have been identified. The world production of pyrethrins falls short of global market demand, stimulating the research in in- vitro production as an alternative to conventional methods. The present work represents a protocol for callus induction and pyrethrins production in Tagetes erecta using ray floret as explant. Studies were carried out on Murashige & Skoog (MS) medium with various concentrations of auxins such as Naphthalene acetic acid ( NAA), Indole 3- acetic acid (IAA), Indole 3- butyric acid (IBA), 2,4 Dichlorophenoxyacetic acid (2,4. D) and cytokinins such as kinetin (KIN), Benzylaminopurins (BAP) for pyrethrins production in ray floret of Tagetes erecta. Among the various concentrations the best hormonal combinations required for pyrethrins production was 2.0 mg/L NAA and 5.0 mg/L KIN. These calli produced 0.54 â„… pyrethrins in six weeks period. The percentage of pyrethrins was increased further by feeding the tissue with various concentrations of ascorbic acid. The maximum pyrethrins content 1.5 % was observed on six week old callus culture obtained on medium containing 2.0 mg /L NAA and 5.0 mg/L KIN supplemented with 350 mg /L ascorbic acid. The protocol developed will open up prospect for in-vitro regeneration of Tagetes erecta to ensure regular supply of authentic raw materials and also help in manipulation of the process leading to increased production of pyrethrins.

Keywords: Tagetes erecta, pyrethrins, callus induction, auxin, cytokinin.