Effect of enhanced UV-B radiation on adaxial leaf surface micromorphology and epicuticular wax biosynthesis of sugar maple

Sugar maple (Acer saccharum [Marsh.]) seedlings were exposed to UV-BBE ranging from 0.61 kJ m−2 d−1 to 12.48 kJ m−2 d−1 Increasgin UV---B intensity was associated with changes in micromorphological characteristics of the adaxial leaf surface. In vivo incorporation of [1− 14C] acetata into sugar maple adaxial leaf surface epicuticular wax indicated (p<0.05) decrease in wax biosynthesis. The proportion [1−14C] acetate incorporated into each of the different epicuticular wax classes changed with increaseing UV---B. Incorporation of [1− 14C] acetate into alkyl esters decreased while incorporation into alkanes increased with increasing UV---B dose. The effects of enhanced UV---B dose recorded in this experiment may have implications for cuticle function