Abstract
These studies were carried out for the development of non-invasive and continuous moni-toring technique of plant growth in the plant factories.
In this kind of facilities, the environmental factors such as ambient temperature, relative humidity, light intensity, pH of nutrient solution are measured and reported with high accuracy. But, data on plant growth are not measured almost or at all even nowadays.
We have, therefore, tried to apply the method of image processing and obtained sufficient results. They are summarized as follows.
(1) We have developed the plant growth monitoring system by image processing with a personal computer for the plant factories.
(2) The leaf area was regarded as the most useful index of vegetable (lettuce) growth as a non-invasive method.
(3) It was linear to the fresh weight with high coefficient of correlation (>0.95) .
(4) The scheduled harvest was achieved by these techniques.
