Callus mediated regeneration through cotyledonary and hypocotyl explants in chilli (Capsicum annuum L.)

Abstract

Chilli is recalcitrant to in vitro regeneration and many factors
such as genotypes, explants and growth regulators play
important role in in vitro indirect organogenesis. The present
study was undertaken to standardize callus mediated
regeneration protocol through indirect organogenesis in
four Indian chilli cultivars namely, KtPL-19, Pusa Sadabahar,
ArCH-001 and Salem. Cotyledonary and hypocotyls
explants were excised from 21-day old in vitro raised
seedlings and subjected to different treatments for callusing
and subsequent regeneration. Full-strength Murashige and
Skoog (MS) medium was found better than half strength
MS medium (MS/2) and B5 medium for culture initiation.
Callus induction in both cotyledonary leaf (98.11%) and
hypocotyl (97.97%) explants was the maximum on MS
medium containing 5.0 mgL-1 2, 4 dicholorophenoxy acetic
acid (2, 4-D) +1.0 mgL-1 kinetin (Kn). For callus multiplication,
the combination consisting of MS+ 3.0 mgL-1 2,4-D+0.5 mgL-
1 kinetin was found to be the best. Shoot bud induction was
achieved on hypocotyl derived callus, when thidiazuron
(TDZ) (1.5 mgL-1) was used as a source of cytokinin in MS
medium.