GROWTH AND FLOWERING RESPONSE OF EASTER LILY CULTIVARS ACE AND NELLIE WHITE TO HID LIGHTS, BOTTOM HEAT, AND GROWTH RETARDANT TREATMENTS

Abstract

Easter lily cultivars Ace and Nellie White were treated with three concentrations of a-cyclopropyl-a-(p-methoxyphenyl-5-pyrimidinemethanol) [Ancymidol] and grown in a standard potting mix under normal greenhouse conditions and established cultural procedures with and without bottom heat and HID lights. A significantly greater number of flowers were produced in Cv. Ace when exposed to HID lights alone, and when given bottom heat in the absence of light. However, significantly fewer flowers were produced in this Cv. when exposed to combined treatments of light and heat. Bottom heat treatment resulted in significantly taller plants in Cv. Ace. Neither bud count, height, nor number of days to flower were affected in Cv. Nellie White as a result of exposure to supplemental light or bottom heat treatments. Neither concentration of Ancymidol resulted in increased flower production. However, it caused a reduction in flower production in Cv. Ace both in the presence and absence of HID lights, and in the heat plus light treatment. Ancymidol was most effective in height control when light was given and heat withheld. At concentrations of 125 and 250 ppm it was effective without regard for heat or light treatment combinations.