Search Results

You are looking at 1 - 1 of 1 items for

  • Author or Editor: L.E. Hedley x
Clear All Modify Search
Full access

C.H. Blazquez, H.N. Nigg, L.E. Hedley, L.E. Ramos and S.E. Simpson

Spectral reflectance measurements were taken from immature and mature leaves of `Rio Red' grapefruit `McCarty' grapefruit `Minneola' tangelo, `Satsuma' mandarin, `Dancy' tangerine, `Nagami' oval kumquat, and `Valencia' orange from 1330 to 1530 hr 1 day at the Florida Citrus Arboretum, Division of Plant Industry, Winter Haven, Fla. A PS-1000 spectrometer was used with fiber optic cables and a lens source (visible range of the spectrum 400-800 sun) coupled with a tungsten halogen light source. A data acquisition card was connected to a notebook computer with a SpectraScope computer program for processing and data storage. Immature and mature leaves of `Minneola' tangelo had greater percentage reflectance in the 500-800 sun range than the other cultivars and leaf ages measured. More detailed information was obtained with the PS-1000 than with conventional spectrometers. The slope of the citrus spectral curves in the 800 nm range was not as sharp as conventional spectrometers, but had a much higher reflectance value than those obtained with a different spectrometer. The system used here was convenient to transport and use in the field and produced clear, interpretable data.