Abstract: Taking two-year-old peach tree of cv ‘Chunjie’ as test material, the natural inducing factors of peach bud dormancy and the roles of Ca²⁺ in the dormancy induction were studied. The results revealed that peach plant was very sensitive to short sunlight and/or natural low temperature. These two factors could induce growth cessation, dormancy, and freezing-resistance development, but their action mechanisms differed with each other. Short sunlight induced the dormancy first and the freezing-resistance then, whereas natural low temperature was in adverse. In case of the co-function of short sunlight and low temperature, i.e., under the natural condition, short sunlight was the main factor inducing growth cessation, dormancy, and freezing-resistance development, while natural low temperature was the secondary one. The inducement effect of short sunlight was closely related to the actions of Ca²⁺, because Ca²⁺ played a messenger role in the signal transduction of short sunlight. In the experiment of supplemental light, it was found that with the decrease of temperature, the Ca²⁺ had an increasing influx from the vacuole, intercellular space, and cell wall to the cytosol and nuclei. At the same time, plant growth slowed down and finally ceased, dormancy started then, and freezing-resistance developed, which indicated that as a messenger in the signal transduction of natural low temperature, Ca²⁺ played an important role in the inducement of growth cessation, dormancy, and freezing-resistance development by natural low temperature.

Key words: size dependence, ecological stoichiometry, Nitraria tangutorum, allometric growth