* Corresponding author. E-mail addresses: [email protected] (M. Fang). 1537-5110/$ – see front matter a 2009 IAgrE doi:10.1016/j.biosystemseng.2009.12.008 Heavy metal stress in soils results in subtle changes in leaf chlorophyll concentration, which are related to crop growth and crop yield. Accurate estimation of the chlorophyll concentration of a crop under heavy metal stress is essential...

increasing energy demands associated with economic growth and industrialization have resulted in dramatic increases in air pollution emissions. air pollution damages the plant mainly by disrupting cell homeostatic conditions.in the present study, diverse plant criteria indicating air pollution from different levels including cell biochemistry, leaf and tree crown in the plane-tree were determin...

Pea plants, grown hydroponically, were supplied with different amounts of iron (Fe) ranging from complete deficiency to toxicity. Plant growth, chlorophyll and carotenoid content and chlorophyll fluorescence parameters were recorded at 7-day intervals from day 20 to day 41. Growth decrease, caused by Fe deficiency or excess as a rule accrued with strengthening and prolongation of the imposed st...

-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...

Chlorophyllase (CLH) is a common plant enzyme that catalyzes the hydrolysis of chlorophyll to form chlorophyllide, a more hydrophilic derivative. For more than a century, the biological role of CLH has been controversial, although this enzyme has been often considered to catalyze chlorophyll catabolism during stress-induced chlorophyll breakdown. In this study, we found that the absence of CLH ...

In a previous paper (l), studies were made of chlorophyll degradation products frequently to be found in leaf extracts. The solation of spectroscopically pure chlorophylls a and b was then considered (2). The logical outcome of these studies is the application of the data to the determination of chlorophyll in extracts. It is complicated by the suggestion that chlorophyll as known to Willstatte...

In a previous paper (l), studies were made of chlorophyll degradation products frequently to be found in leaf extracts. The solation of spectroscopically pure chlorophylls a and b was then considered (2). The logical outcome of these studies is the application of the data to the determination of chlorophyll in extracts. It is complicated by the suggestion that chlorophyll as known to Willstatte...

High-throughput, noninvasive field phenotyping has revealed genetic variation in crop morphological, developmental, and agronomic traits, but rapid measurements of the underlying physiological and biochemical traits are needed to fully understand genetic variation in plant-environment interactions. This study tested the application of leaf hyperspectral reflectance (λ = 500-2,400 nm) as a high-...

Soybean (Glycine max [L.] Merr.) germplasm, isogenic except for loci controlling male-sterility (ms(1)) and nodulation (rj(1)) was utilized to investigate the effects of reproductive tissue development and nitrogen source on the initiation of monocarpic senescence. The experimental genotypes (Ms(1)Rj(1), Ms(1)rj(1), ms(1)Rj(1), and ms(1)rj(1), were selected from a cross between N69-2774 and N59...