Fast identification of pesticide residue level in lettuce leaves plays a key role in the test of food safety. In order to identify the different concentrations pesticide residues of lettuce leaves in a fast and nondestructive way, the hyperspectra coupled with chlorophyll fluorescence spectra was used in this research. Transmission electron microscopy (TEM) was used to identify the microstructu...

When spinach (Spinacia oleracea) leaf discs were incubated in a dark anaerobic environment, the chlorophyll fluorescence yield was much increased relative to the aerobic control. Occasionally, the fluorescence yield of the darkened anaerobic samples approached 80% of the maximum fluorescence. The anaerobic incubation period also induced in a leaf disc the capacity to exhibit a low light-mediate...

The steady state absorption and fluorescence spectroscopic properties of the xanthophylls, violaxanthin, zeaxanthin, and lutein, and the efficiencies of singlet energy transfer from the individual xanthophylls to chlorophyll have been investigated in recombinant CP26 protein overexpressed in Escherichia coli and then refolded in vitro with purified pigments. Also, the effect of the different xa...

Chlorophyll fluorescence and hyperspectral reflectance were used to evaluate physiological responses to two common stressors in coastal environments. Chlorophyll content is one indicator of drought and salinity vegetation stress because of its direct role in the photosynthetic process and electron transport. Recent advances in fluorescence spectroscopy have led to the development of numerous re...

Measurements of chlorophyll fluorescence provide an elegant and non-invasive means of probing the dynamics of photosynthesis. Advances in video imaging of chlorophyll fluorescence have now made it possible to study photosynthesis at all levels from individual cells to entire crop populations. Since the technology delivers quantitative data, is easily scaled up and can be readily combined with o...

Frank Terjung Fachbereich Physik, Carl von Ossietzky-Universität Oldenburg, D-26111 Oldenburg, Germany Z. Naturforsch. 53c, 924-926 (1998); received May 18/June 9, 1998 Fluorescence Lifetimes, Photosystem II, Reabsorption of Fluorescence Effects of reabsorption of chlorophyll fluorescence were investigated in measurements on chloroplasts and higher plant leaves. The excitation was performed at ...

in order to quantify and simulate the response of lemon balm (melissa officinalis l.) plants to cadmium (cd) concentrations in the soil, a pot experiment was conducted using completely randomized design (crd) with three replicates during 2014. the treatment consisted of twelve cd concentrations from 0 to 300 mg kg-1 of cd in the soil which was mixed with the experimental soil before planting. l...

We have extended a conventional photosynthesis model to simulate field and laboratory measurements of chlorophyll fluorescence at the leaf scale. The fluorescence paramaterization is based on a close nonlinear relationship between the relative light saturation of photosynthesis and nonradiative energy dissipation in plants of different species. This relationship diverged only among examined dat...