Abstract

Friable, embryogenic calli of F1 cucumber (Cucumis sativus) cultivar, Royal, were induced from the hypocotyl pieces cultured on solidified MS-basal media supplemented with 2,4-dichlorophenoxy acetic acid (2,4-D) and benzyl amino purine (BAP). Embryogenic calli were transferred to liquid Murashige and Skoog (MS)-basal media supplemented with 5 µM naphthaleneacetic acid (NAA) and 1 µM BAP. The mature somatic embryos were encapsulated in sodium alginate mixture in synthetic seeds. The encapsulation mixture containing 3% sodium alginate, 100 mM calcium chloride and one-fourth volume of the cell suspension nutrient mixture containing 5 × 10^-4 somatic embryos per ml was found the best. Synthetic seeds remain viable up to 14 weeks when stored at 4°C. Germination efficiency of synthetic seeds was decreased to 57% after 10 weeks of storage followed by rapid decrease in survival rate to 0% after 15 weeks. Genetic diversity between mother plants and in vitro produced synthetic seeds showed resemblance as assessed by amplified fragment length polymorphism (AFLP) markers.

Key words: Artificial seed, Cucumis sativus, encapsulation, somatic embryogenesis, sodium-calcium alginate.

Abbreviation

CH, Casein hydrolysate; AFLP, amplified fragment length polymorphism; 2, 4-D, 2, 4 dichlorophenoxy acetic acid; BAP, benzyl amino purine; MS, Murashige and Skoog; NAA, naphthaleneacetic acid; AFLP, amplified fragment length polymorphism; RFLP, restriction fragment length polymorphism; SSR,simple sequence repeats; RAPD, random amplification of polymorphic DNA; CH,casein hydrolysate; GA₃, gibberellic acid; PCR, polymerase chain reaction; PLBs,protocorm like bodies.