GROWTH OF IMMATURE PEACH EMBRYOS IN RESPONSE TO MEDIA, OVULE SUPPORT METHOD, AND OVULE PERFORATION

The influence of medium formulation, methods of ovule support, and ovu le perforation on in vitro growth of immature peach [Prunus persica (L .) Batsch] embryos (4.0 to 8.7 mm long) was investigated. Maximum embr yo dry weights were attained with vermiculite support, ovule perforati on, and 10% sucrose in the medium. At high sucrose levels, all three t ested media (Monnier, modified Murashige and Skoog, or modified Stewar t and Hsu medium) performed similarly. Adding IAA and kinetin to cultu re media did not enhance embryo growth. Using the vermiculite support system, small embryos of early maturing peach cultivars, obtained at f ruit maturity, were cultured successfully and used as maternal parents in breeding programs. Chemical name used: indole acetic acid (IAA).