A new form of chlorophyll c has been isolated from the pyrmnesiophyte Pavlova gyrans Butcher. This pigment is spectrally similar to chlorophyll c(2), but all the absorption maxima (454, 583, and 630 nm in diethyl ether) are shifted 4 to 6 nanometers to longer wavelengths. The new pigment can be separated from other chlorophyll c-type pigments by reversed-phase high performance liquid chromatogr...

We conducted two experiments to determine the usefulness of a chlorophyll content meter (CCM) for the measurement of foliar chlorophyll concentration in sugar maple (Acer saccharum Marsh.) in the fall color period. In Experiment 1, four sugar maple trees were visually assigned to each of four fall foliage color categories in October 1998. On four dates in the fall of 1999, leaves were taken fro...

We measured needle pigment content and photosynthetic rates of 1-year-old western larch (Larix occidentalis Nutt.) during autumn foliar senescence. Chlorophyll (Chl) and carotenoid (xanthophyll + b-carotene) contents of needles declined 11 and 17%, respectively, before CO(2) assimilation rate began to decline. Chlorophyll a/b ratio, Chl/carotenoid ratio, photochemical efficiency (F(v)/F(m)), an...

-In this study, impacts of vector quantization compression on prediction of leaf chlorophyll content of crops for the application to precision agriculture were evaluated. The compression algorithm tested in this paper is called successive approximation multi-stage vector quantization (SAMVQ). The hyperspectral data used were acquired by CASI over corn fields at L’ Acadie experimental farm (Agri...

The usefulness of nondestructive methods for measuring chlorophyll content in skin of ‘Golden Delicious’ apples and for evaluating quality parameters and fruit maturity using optical reflectance spectrometry was studied. The fruit weight, firmness, total soluble solids content and titratable acidity during vegetation period and short-term storage at 10°C of ‘Golden Delicious’ apples were measur...

Fruit reflectance spectra of five apple (Malus domestica Borkh.) cultivars (Zhigulevskoe, Antonovka, Granny Smith, Golden Delicious and Renet Simirenko) with a wide range of peel pigment (chlorophylls a and b , carotenoids and anthocyanins) content have been studied to develop non-destructive techniques for pigment assessment. In addition to chlorophylls, positions of in vivo absorption maxima ...

Growth parameters and total pigment content (chlorophyll a+b and carotenoids) were investigated through postgermination, greening, natural senescence and subsequent rejuvenation of intact cotyledons of Cucurbita pepo L. (zucchini). Dark-induced senescence and recovery of the cotyledons after 2-day darkening of a whole plant were also studied. Results showed significant increase in the fresh wei...

Predictions of chlorophyll content (chla+b) or any other canopy biophysical parameter from airborne or satellite canopy reflectance are generally carried out through four different methodologies: i) directly studying the statistical relationships between ground-measured biochemical data and canopy-measured reflectance (Johnson et al., 1994; Matson et al., 1994); ii) applying the leaf-level rela...

Changes in pigment content allow seagrasses to photo-acclimate to dynamic light environments, but lightand salinity-induced stress may reduce this ability. In this study, Thalassia testudinum seedlings were exposed to two light treatments (50 – 70% reduction and full sun) and three salinity treatments (20, 35, and 50) in a 44-day mesocosm experiment. Variation in leaf pigment content (chlorophy...

The cyanobacterium Spirulina platensis is an attractive alternative source of the pigment chlorophyll, which is used as a natural color in food, cosmetic, and pharmaceutical products. In the present investigation, the influence of light intensity and pH for Spirulina platensis growth, protein and chl a content were examined. In the present investigation the production of Spirulina platensis was...