Temperature Control of Physiological Dwarfing in Peach Seedlings

Abstract

ONE of the key problems in germination physiology is the mechanism of embryo ‘dormancy’ or rest. One aspect of this problem is the physiological dwarfing which has been reported to occur in the seedlings of woody plants, especially of such commercial fruits as peaches. These seeds normally require an extended period of low-temperature after-ripening to permit germination. However, if the seed-coat is removed from non-after-ripened seeds germination occurs, but the shoots of such plants are abnormal with telescoped internodes and leaves which may be deformed or sometimes reduced to a rosette of white, scale-like appendages^1,2; the exact symptoms are a varietal characteristic³. Low-temperature after-ripening of the seed or seedling is commonly reported to be essential to produce a normal plant.