Twenty six accessions of grain Amaranth (Amaranthus hypochondriacus L.) were evaluated for salient biochemical and quantitative traits particularly reference to chlorophyll a and b, total chlorophyll, phenol content, leaf moisture, leaf protein content, test weight and yield plant. Genetic divergence and association among these traits were analysed. Chlorophyll a, chlorophyll b, total chlorophy...

Farmers must balance the competing goals of supplying contributions of background reflectance, while spectral vegetation indices that combined reflectances of near-infrared adequate N for their crops while minimizing N losses to the environment. To characterize the spatial variability of N and other visible bands (MCARI and NIR/Green) were responsive to both leaf chlorophyll concentrations and ...

Attached apple leaves (Pyrus malus L., Golden Delicious) began to lose protein in early August as the first sign of senescence. Apple leaf discs prepared from samples before early August gained protein for up to 7 days after detachment. After early August, the loss of protein from leaf discs was no greater than the loss from attached leaves in 7 days. The loss of chlorophyll from leaf discs beg...

The Soil Plant Analysis Development (SPAD) chlorophyll meter is one of the most commonly used diagnostic tools to measure crop nitrogen status. However, the measurement method of the meter could significantly affect the accuracy of the final estimation. Thus, this research was undertaken to develop a new methodology to optimize SPAD meter measurements in rice (Oryza sativa L.). A flatbed color ...

Spatial and temporal variations in canopy structure and leaf biochemistry have considerable influence on fluxes of CO2, water and energy and nutrient cycling in vegetation. Two vegetation indices (VI), NDVI and Macc01, were used to model the spatio-temporal variability of broadleaf chlorophyll content and leaf area index (LAI) across a growing season. Ground data including LAI, hyperspectral le...

Shade and sun leaves of Valencia orange [Citrus sinensis (L.) Osbeck] were collected to evaluate comparative effects of their leaf chlorophyll concentration, water content, thickness, and mesophyll volume of air on visible light reflectance, specifically the 0.45-, 0.55-, and 0.65-#m wavelength (WLs). The reflectance at the 0.45-, 0.55-, and 0.65-/~m WLs of sun leaves but not shade leaves was n...

One of the main factors affecting vegetation productivity is absorbed light, which is largely governed by chlorophyll. In this paper, we introduce the concept of chlorophyll efficiency, representing the amount of gross primary production per unit of canopy chlorophyll content (Chl) and incident PAR. We analyzed chlorophyll efficiency in two contrasting crops (soybean and maize). Given that they...

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...

During natural or dark-induced senescence, chlorophyll degradation causes leaf yellowing. Recent evidence indicates that chlorophyll catabolic enzymes (CCEs) interact with the photosynthetic apparatus; for example, five CCEs (NYC1, NOL, PPH, PAO and RCCR) interact with LHCII. STAY-GREEN (SGR) and CCEs interact with one another in senescing chloroplasts; this interaction may allow metabolic chan...

Wood structure and wood anatomy are usually considered to be largely independent of the physiological processes that govern tree growth. This paper reports a statistical relationship between leaf and bark chlorophyll fluorescence and wood density. A relationship between leaf and bark chlorophyll fluorescence and the quantity of wood decay in a tree is also described. There was a statistically s...