Growth of vinca (Vinca major (L.)) was limited by either a medium drench application of uniconazole of 2 or 4 mg a.i. per pot or a foliar spray application of 2, 4, or 6.25 mg a.i. per plant, both applied in 25 ml (0.75 fl oz) of water. Shoot length, leaf number, leaf area, leaf dry weight and stem dry weight averaged over uniconazole treatments were 51%, 45%, 32%, 33%, and 38% less than control plants, respectively. When compared to control plants, water use of chemically treated plants was reduced by 35% due to the reduction of leaf area and also lower stomatal conductance readings. Stomatal conductance readings of chemically treated plants were 2 to 5 times less than control plants indicating the plant size was not the only factor affecting plant water use.
Texas Agricultural Experiment Station Journal Article no.TA30652. We gratefully thank Hines Nurseries, Brookshire, Texas, for donation of plant materials.
2County Extension Horticulturist and Associate Professor, respectfully.