DEVELOPMENT OF A PHOTOGRAPHIC SCALE FOR THE VISUAL EVALUATION OF APPLE STRIPE DENSITY

This research developed a photographic scale for the evaluation of str ipe density for 5 apple cultivars (Carousel, 8M-15-10, Fuji, Gala, and Jonagold) using a series of two experiments. In Experiment I, subject s were able to significantly discriminate and reproducibly score the s tripe density of apples using unstructured graphic line scales. Photog raphs of selected apples were then labelled with the corresponding mea n scores and used as visual references for Experiment 2. In Experiment 2, subjects reproducibly evaluated the stripe density of apples using structured line scales (anchored with 3 or 5 photographic references) , with similar mean scores from the 3- or 5-point scales. Subject diff ered very little in their variances reflecting the potential usefulnes s of these line scales for commercial evaluation of apple stripe densi ty in whole apples.