PHYSICAL UNIFORMITY OF GRADED RAILCAR AND VESSEL SHIPMENTS OF CANADA-WESTERN-RED SPRING WHEAT DETERMINED BY DIGITAL IMAGE-ANALYSIS

The application of digital image analysis for objective measurement of grain uniformity in commercial samples of Canada Western Red Spring ( CWRS) wheat was investigated. Official railcar-unloading (carlot) and vessel-loading (cargo) samples of three grades (Nos. 1, 2 and 3) of CW RS wheat were analyzed for 16 kernel-size, shape and brightness featur es that were automatically computed from digital images acquired in re flected light. Based on a subsample of 400 kernels for each graded sam ple, coefficient of variation (CV) data were used to evaluate the infl uence of grading and bulk handling on the uniformity of carlot and car go shipments. A significant and progressive decrease in sample uniform ity for No. 2 and No. 3 carlot samples, compared with No. 1, was obser ved for all computed kernel features. Averaged over all features, the decreases in uniformity in carlot samples were 13.4 and 13.7% with gra de lowering from No. 1 to No. 2 and from No. 2 to No. 3, respectively. For cargo samples, an analogous effect was found as the grade dropped from No. 2 to No. 3 only. There was essentially no measurable differe nce in the level of uniformity, averaged over all kernel features, bet ween No. 1 and No. 2 cargo samples, which were extremely uniform, as i ndicated by CV values of 1.27 and 1.25%, respectively. The effect of t he bulk handling system was evidenced by a substantial improvement in uniformity of cargo samples compared with carlot samples. Averaged ove r all features, CV values for cargo samples were lower than CV values for corresponding carlots by 58, 63 and 64% for grade Nos. 1, 2 and 3, respectively.