Wai ks; Newman Se 1992

• Authors: Wai ks; Newman Se
• Title: Air and root-zone temperatures influence growth and flowering of snapdragons
• Location: Hortscience, 27 (7). 1992. 796-798.
• Abstract: growth chamber studies using elevated root-zone temperatures and greenhouse studies using two root-zone and two night air temperatures were conducted to determine the effects on growth and flowering of two response groups ('rainier white' (group ii) and 'tampico' (group iii)) of cut-flower snapdragons (Antirrhinum majus l.). chamber-grown snapdragons with the root zone at 30c had shorter stems and a lower dry weight than those at 20c. holding the root zone above 26c increased time to flower. greenhouse-grown 'tampico' and 'rainier white' snapdragon stems were longer with increased root-zone temperature regardless of night air temperature. time to flower was reduced an average of 6 days with increased root-zone temperature and 12 days when the night air was maintained at 20c. this study demonstrated that the effects of relatively low greenhouse temperatures may be offset by root-zone heat.