MEASUREMENT OF GROWTH OF PLUG SEEDLINGS BY IMAGE PROCESSING IN BROCCOLI

Color image processing technique was applied a non-destructive measurement of growth of plug seedlings of broccoli in a group. Video images of plug seedlings of broccoli were taken with a video camera fixed over the object under artificial light condition. The RGB chrominance levels (r, g, and b) were calculated from the gray-tone levels in such a manner that r=256xR/(R+G+B), g=256xG/(R+G+B), and b=256xB/(R+G+B). Image discrimination of plug seedlings from the background was made possible by applying thresholds of the chrominance levels in the image processing procedure. The area ration of plug seedlings to background in the image frame was correlated with top fresh weight(R²=0.962) and leaf area of plugseedlings (R²=0.981). The average chrominance g-level of plug seedlings was also correlated with chlorophyll content (R²=0.952) of plug seedlings.