Gibberellic Acid and the Chilling Requirements of Peach Seeds

Abstract

PEACH seeds normally have to be stratified at a low temperature for approximately two months before they germinate. Unstratified seeds can be made to germinate by removal of the seed coats1, and experiments performed at this Institute2 indicate that unstratified embryos lack the power to overcome the mechanical resistance offered by the seed coats. The seedlings obtained from unstratified excised embryos develop dwarfed shoots with abnormally short internodes and the leaves are often distorted. This shows that the chilling requirements are not concerned with germination alone. The shoot apex of the embryo appears to be the main part of the seedling which requires cold treatment to ensure normal development. The roots show no apparent abnormal symptoms, and shoots which develop from lateral buds seem normal in all respects.