Influence of Localized Low Temperature on Biloxi Soybean During Photoperiodic Induction

The influence of low temperature in suppressing flower-bud initiation in Biloxi soybean has been considered from three points of view: its influence upon the differentiation of flower buds from the meristems; its influence on translocation of a flower-forming stimulus from the leaves to the growing points; and its influence upon those processes in the leaf that bring about flower-bud formation. Data are presented on the first two of these points; the last is being subjected to further investigation. 2. Fewer flower buds were formed in response to a 4-day induction treatment on plants bearing a single leaf if the terminal buds or the petioles were cooled to 3⚬ C. than if they were not cooled. When the temperature was raised to 10⚬ C. the inhibiting effect on flowering decreased in both types of experiments, but even at this temperature only slight growth of the terminals occurred during the induction treatment. 3. Petiole-cooling experiments involving plants with two leaves indicate that inhibition of flowering resulted from the influence of low temperature on the transport of a flower-forming stimulus.