Effect of temperature and light on foliar absorption of P and Rb by Chrysanthemum and Pilea

Abstract

Young plants of Pilea cadierei Gagnep Guillaum and Chrysanthemum morifolium Ramat. 'Giant # 4 Indianapolis White' were grown in Hoagland's solution in growth chambers. Their leaves were treated with rubidium phosphate double labelled with ³³P and ⁸⁶Rb. Light intensity, period of pretreatment in light or dark, daylength, and air temperature had different influences on foliar uptake of each ion, as did plant species and leaf surface. With all variables tested, uptake and translocation of Rb was much greater than of P. Absorption of both P and Rb through the lower surface was as much as 8 times greater than through upper surface, especially with Pilea. Light had a greater effect upon uptake of both P and Rb by Chrysanthemum than by Pilea, but did not influence uptake as much as previously reported.