The five spectra shown in the above chart are of the reflectances at various places on a broccoli flower. These spectra can provide an indication of the growth of broccoli and have a relationship to the freshness of the flower.

The two spectra of portions of the flower are from (1.) a "grayer" section of the flower and (2.) a ‘greener’ section of the flower. Because of the openings between the individual flower buds, the measured reflectances are low. The leaf (3.) provides a typical photosynthetic response showing high rejection of infrared radiation. Reflectances of the stem are relatively high in the visible; the portion of the stem directly below the flower (4.) Is lighter (has a higher reflectance) than the portion of the stem (5.) which is lower down (further away from the flower).

All spectra were taken with an Ocean Optics spectrometer. Illumination was provided by an Ancal ALS-15 light source and a reflectance probe; one leg was coupled to the light source for illumination and the other leg was coupled to the spectrometer for signal reception. A standard white was used as a reference for these measurements..

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For further information on acquiring reflectance spectra, contact Bud Wood at Ancal, Inc.; E-mail: budwood@ancal.com