METHYL JASMONATE VAPOR PROMOTES BETA-CAROTENE SYNTHESIS AND CHLOROPHYLL DEGRADATION IN GOLDEN DELICIOUS APPLE PEEL

Methyl jasmonate (JAMe) vapors (less than or equal to 8 ppm) for 4 h a t 25 degrees C dramatically increased Golden Delicious apple peel beta -carotene synthesis by nearly threefold to 35 ng/mm(2), while control fruits remained nearly constant at 11 ng/mm(2) during the 10 day measu rement period. Chlorophyll a and to a lesser extent chlorophyll b and lutein degradation were accelerated by JAMe treatment, but all showed some recovery after 6 days. Peel chlorophyll a:b ratio held almost con stant at 4.2-4.5 in control fruits during 10 days, while JAMe-treated apple chl a:b ratio decreased linearly to 2.9 during 10 days.