Scanning Electron Microscopy of the Surface of Pickling Cucumber Fruit1

Abstract

Abstract Scanning electron microscopy revealed the presence of stomata, trichomes, scars left by detached trichomes, and epidermal cells on the surface of fresh, pickling cucumbers. Size, frequency and distribution of stomata were determined. Stomata, recessed several qm, were the only apparent, natural openings in the epidermis for gas exchange. Stomata were most numerous in the middle (20.2/mm2), less in the blossom end (10.4/mm2) and essentially absent in the stem end section of large (3.8–5.1 cm diameter), ‘GY14’ fruit. Stomatal frequency on large fruit was only about one-third that on small (1.9–2.7 cm diameter) fruit, but the stomatal index for the middle section of each size was similar (0.17–0.18). Large ‘GY14’ fruit were estimated to contain 130,000 stomata, with potential stomatal pore area (assuming open guard cells) representing 0.062% of the fruit surface