Essential oils from aerial parts of Mentha spicata, was obtained by steam destillation using a Clevenger-type system. These oils were screened for antibacterial and anti-Candida albicans activity using bioautographic method. A fiel experiments was laid out in agricultural research farm, city Namin, Ardabil province, Iran in 2013. Experiment was conducted in a randomized complete block with seve...

Essential oils from aerial parts of Mentha spicata, was obtained by steam destillation using a Clevenger-type system. These oils were screened for antibacterial and anti-Candida albicans activity using bioautographic method. A fiel experiments was laid out in agricultural research farm, city Namin, Ardabil province, Iran in 2013. Experiment was conducted in a randomized complete block with seve...

In situ optical meters are widely used to estimate leaf chlorophyll concentration, but non-uniform chlorophyll distribution causes the opticalmeasurement to vary widely among species for the same chlorophyllconcentration. Over 30 studies have sought to quantify the in situ/in vitro (optical/absolute) relationship, but neither chlorophyll extraction normeasurement techniques for ...

The effect of short-term water stress on photosynthesis of two sunflower hybrids (Helianthus annuus L. cv Sungro-380 and cv SH-3622), differing in productivity under field conditions, was measured. The rate of CO(2) assimilation of young, mature leaves of SH-3622 under well-watered conditions was approximately 30% greater than that of Sungro-380 in bright light and elevated CO(2); the carboxyla...

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...

This work introduces a new vision-based approach for estimating chlorophyll contents in a plant leaf using reflectance and transmittance as base parameters. Images of the top and underside of the leaf are captured. To estimate the base parameters (reflectance/transmittance), a novel optical arrangement is proposed. The chlorophyll content is then estimated by using linear regression where the i...

An underwater optical serial-sectioning technique is developed to measure in situ three-dimensional distributions of biological particles. The technique involves scanning of a thin plane of laser light through a range of distances parallel to the imaging plane of a digital CCD camera. Images of induced fluorescence in the sequentially illuminated planes are recorded. An inverse method is then u...

Figure 1. Encalypta rhabdocarpa in the alpine region where high-intensity UV light can damage chlorophyll and DNA. Photo by Michael Lüth. Exposure to UV light has been hypothesized as a major deterrent of evolution to land. Both chlorophyll and DNA are easily damaged by high intensities of direct sunlight (Figure 1). In fact, it has been suggested that a major role of lignin, absent in bryophyt...