Use of amino acids for a highly efficient somatic embryogenesis in grapevine 'Crimson Seedless'

Abstract

Somatic embryogenesis influenced by growth regulators and amino acids was studied in in vitro leaves of grapevine 'Crimson Seedless'. In vitroleaves of the cultivar were collected from multiple shoot cultures maintained on Murashige and Skoog’s (MS) basal medium supplemented with 9 μM N⁶-benzyladenine (BA). Among the growth regulators used, BA at 4.5 μM induced higher embryogenic response producing more number of somatic embryos per explant. This response was increased with the addition of 5 μM naphthoxy-1-acetic acid (NOA) to ½ MS containing 4.5 μM BA. Further, supplementation of amino acids in the callus induction medium significantly improved the embryogenic response of in vitro leaves. The higher number of explants showing somatic embryo production (55.3 %) and higher number of somatic embryos per explant (15.5 per explant) were recorded with the supplementation of 5 mM phenylalanine to callus induction medium. Primary somatic embryos showed repetitive embryogenesis on ½ MS medium devoid of growth regulators. Plantlets derived from somatic embryos were transferred to soil-sand-peat mixture (1:1:1 v/v) and hardened plantlets were established in greenhouse with 90 % survival. This somatic embryogenesis system has been successfully used for Agrobacterium-mediated transformation studies in 'Crimson Seedless' in our laboratory. To our knowledge, this is the first report on the use of amino acids for the high efficient somatic embryogenesis in grapevine.