2017 ASHS Annual Conference

Embryo rescue is an in vitro technique used to supplement the nutrients and energy necessary to produce otherwise aborted seedless grape embryos in seedless crosses. Table grape breeding can be enhanced through the use of embryo rescue by allowing seedless x seedless crosses. The University of Minnesota grape breeding progam has begun to investigate the timing and growth media requirements for efficient embryo rescue in cold-hardy, hybrid germplasm. We evaluated which of three growth media treatments was the best for establishing embryos for the following traits: embryo germination, plant appearance, number of leaves, and root system rating. The data were collected at three different timepoints (27 days, 45 days, and 63 days) after transfer from the rescued ovule. Treatment 2, Murashige and Skoog basal media had very low germination and the resulting seedlings performed the lowest compared to the other treatments. There was no significant difference between Treatment 1 (Lloyd & McCown Woody Plant Basal medium with vitamins) and Treatment 3 (same as Treatment 2 with added IAA, gibberellic acid, and casein hydrolysate) for any of the traits, although Treatment 3 averages were consistently higher. Treatments 2 and 3 will be considered for future work for embryo rescue in cold-hardy, hybrid table grape breeding.