PRIYANKA SAINI*, SAPNA BHORIA1 AND RANJANA JAIWAL
Department of Zoology, Maharshi Dayanand University, Rohtak-124 001 (Haryana), India
*(e-mail : 31priyankasaini@gmail.com; **ranjana.jaiwal@gmail.com; Mobile :7015506779)
(Received : March 20, 2019; Accepted : May 18, 2019)
ABSTRACT
Cucumber (Cucumis sativus L.) is one of the most important highly nutritious vegetable crops, popularly grown in the South Asia. Considering its economic and nutritional values, the present study was aimed at developing an efficient protocol for in vitro plant regeneration of cucumber from hypocotyl explants. Hypocotyl explants (10 mm in length) excised from 7-day-old in vitro-raised seedlings of cucumber were cultured on MS medium containing different concentrations of BAP (0-5.0 mg/l). BAP at a concentration of 2.0 mg/l was found to be the most effective (79%) for callus induction. Of the hypocotyl explants cultured in different orientations (horizontal or vertical), the morphologically basal cut end of hypocotyl segments that was in contact with the medium developed callus, whereas the apical end did not form callus. Among the different segments of hypocotyl, the segment which was close to the cotyledons showed the maximum response in terms of callus induction and shoot formation. Hypocotyl explants cultured on basal medium did not form callus. The maximum shoot regeneration from callus was obtained on the MS medium containing BAP (2.0 mg/l) with IAA (0.5 mg/l) and AgNO3 (30 µM). The in vitro developed shoots were rooted on MS medium containing 2.0 µM IBA and plantlets were established in the soil where they developed into mature plants
Key words :Hypocotyl, benzylaminopurine, indole-acetic acid, callus induction and shoot regeneration