SOMATIC EMBRYOGENESIS AND PLANT REGENERATION INDUCED FROM MATURE SEEDS, COTYLEDONS AND SHOOT TIPS OF CUCUMBER.

Khidr, Yehia; El-Absawy, El-Sayed; Mahmoud, Amal; Hasan, Mohamed; Hemeida, Alaa

doi:10.21608/jpd.2012.42464

SOMATIC EMBRYOGENESIS AND PLANT REGENERATION INDUCED FROM MATURE SEEDS, COTYLEDONS AND SHOOT TIPS OF CUCUMBER.

Document Type : Original Article

Authors

¹ Department of Plant Biotechnology, Genetic Engineering and Biotechnology Research Institute, Sadat City, Menofia University

² Department of Bioinformatics, Genetic Engineering and Biotechnology Research Institute, Sadat City, Menofia University

10.21608/jpd.2012.42464

Abstract

Commercial cucumber cultivars were explored for embryogenesis and plant regeneration induced in somatic tissues on plant growth regulators. An efficient in vitro regeneration protocol for Cucumis sativus L via somatic embryogenesis has been developed. Embryogenic callus cultures were established from mature seeds, cotyledons and shoot tips on Murashige and Skoog (MS) medium containing 87.64 µM sucrose, 0.8% agar, 2,4-dichlorophenoxyacetic acid 2,4-D and kinetin. Maximum callus induction (94%, 92%) was observed in cotyledons and mature seeds on MS medium supplemented with 1mg/L 2,4-D, respectively. Somatic embryos were observed on mature seed explants after 17 weeks on MS medium supplemented with 5mg/L2,4-D (33%) and 0.5mg/L α-naphthaleneacetic acid(NAA) (27%). while somatic embryos were observed on cotyledon explants after 18 weeks on MS medium supplemented with 2mg/L 2,4-D (10%) and 0.5mg/L NAA (25%). The highest percentage of somatic embryogenesis (40%) was obtained with 2 mg/L 2,4-D and 0.5 mg/L NAA (30%) on shoot tip explants after 13 weeks. Regeneration of adventitious buds from callus of cotyledon and mature seeds were achieved after 8 weeks on MS medium supplemented with 0.5mg/L and 1mg/L 6-benzyladenine(BA), respectively. In vitro-regenerated plantlets with well-developed roots were successfully hardened in a greenhouse and established in soil.
Generally, auxin was found critical for induction of callus and formation of somatic embryos, while the cytokinin was essential for callus differentiation and plant regeneration.

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