Transformation of Oat Using Mature Embryo‐Derived Tissue Cultures

Abstract

Mature embryos of oat (Avena sativa L.) have been used to establish regenerable tissue cultures with potential use for transformation. The objective of this study was to investigate tissue cultures established from mature embryos of oat as an alternative source of totipotent target cells for microprojectile bombardment‐mediated transformation. Mature embryos of a specific genotype, GAF/Park‐1, were incubated on a tissue culture induction medium for 1, 4, 8, or 9 wk before either being directly bombarded after 1 and 4 wk, or bombarded as tissue cultures initiated after 8 and 9 wk incubation. The 8‐ and 9‐ wk‐old tissue cultures yielded the greatest numbers of transgenic tissue cultures (3.2 transgenic tissue cultures per microprojectile bombardment treatment). Three additional transformation experiments were conducted with mature embryo‐derived 8‐ to 9‐wk‐old tissue cultures to determine the regeneration capacity and production of fertile transgenic plants. Overall, fertile plants were regenerated from 35 of 85 independently derived transgenic tissue cultures. Identification of mature embryo‐derived tissue cultures as a source of transformable totipotent cells should reduce the expense and labor involved in oat transformation. Moreover, the uniformity and convenience of this explant likely will stimulate further investigations in oat transformation efficiency.