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Leaf area is an important canopy parameter, which is available in analyzing plant growth and development. Methods for estimating leaf area can be derived into two categories, direct and indirect method. The direct method is simple and precise, but more time and labor consuming. The objective of this study was to analyze the relationships between the digital camera image and leaf area of rice. Plant samples were collected at 20, 40, 60, 80 and 100 days after planting. The images were captured at a height of 1 meter above the crop canopy at 08:00 a.m., 12:00 a.m. and 04:00 p.m. Leaf area was determined with leaf area meter. Supervised technique was used to classify and calculate the pixel number of images. Finally, the models were conducted in this study. The result showed that leaf area was consistent with the pixel number as the equation; y = 17.24 + 0.01x, R² = 0.60**. The appropriate relationship between leaf area and pixel number at 12:00 a.m. is y = -329.24 + 0.012x, R² = 0.86**
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