FIGURE 5.

(A) Autofluorescence in wounded and unwounded (control) roots stored at 6 and 12°C for up to 28 days. Autofluorescence indicates the presence of suberin and lignin polyphenolic compounds. Roots were wounded by abrading the root surface with a wire brush after harvest and were subsequently stored at 94% relative humidity. Representative transverse sections of root surface tissues are presented. Gold–brown pigmentation at the outermost cell layers in wounded roots is believed to be melanin. Bar = 100 μm. In (B), the autofluorescence of wounded tissue stored at 6 and 12°C for 28 days are enlarged to accentuate differences in suberization between roots stored at the two temperatures.