Colour vision to determine paddy maturity

Quality of harvested rice and its production are influenced by the timing of harvesting. Harvesting at the right stage gives the best yield and quality. The purpose of this research was to determine the best time for harvesting by using image processing technique. Parameters such as weight of florets, hue colour of florets, and hue colour of flag leaf were tested in the research. The trends of changes were observed in the process of maturity until the harvesting day. For Malaysia Rice (MR) variety 219, the corresponding hue value for florets maturation is 32.3o ±2o. In the period of maturity, the florets’ hue value decreased from green to yellow and then remained constant at 32o. The maturity process proceeded gradually from the florets at the outermost spikelet to florets at the basal part. Florets at the basal part were matured seven days later than the florets at the terminal part. Results show that the colour changes of the leaf were uneven and hence did not give a good correlation with maturity. It was observed that the weight for a matured floret increased rapidly towards maturity, but remained constant after it reached the mature stage. There were some losses in weight due to the decrease of moisture contents in florets. Finally, it was concluded that the maturity of paddy can be observed through the colour and weight of florets. The MR219 mature floret has the hue colour of 32.3o ±2o, and the mature floret can weigh up to 31.25 mg.