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Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan

Citation:   No Citation available.
Authors:   Trevor P Kondratowicz, Trever G Crowe

In order to understand the effects that nutrients (nitrogen, phosphorus, and potassium) and water have on the reflectance of canola leaves, two canola varieties were grown while controlling quantities of nutrients and water supplied to plants inside a growth chamber. Two levels of each nutrient (N, P, K) and water were imposed. A nutrient distribution system, consisting of a pump, solenoid valves, emitters, and a data logger was designed to accurately administer nutrients and water to these plants. When the plants reached the fifth leaf stage, the first four leaves were removed from the plants and scanned with a spectrophotometer and SPAD meter. Two analyses were completed on the data set: a classification, and a general trend analysis. Classification techniques were used to classify each treatment, and a general trend analysis showed visually the differences between treatments. Information from such a study is important in areas concerning selective herbicide and fertilizer application, wherein a sensor could determine whether a plant is lacking a nutrient or water, and how plants grown under different conditions appear spectrally.

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