The regulatory role of ethylene in leaf senescence was studied with excised tobacco leaf discs which were allowed to senesce in darkness. Exogenous ethylene, applied during the first 24 hours of senescence, enhanced chlorophyll loss without accelerating the climacteric-like pattern of rise in both ethylene and CO(2), which occurred in the advanced stage of leaf senescence. Rates of both ethylen...

The highly variable leaf color of Cymbidium sinense significantly improves its horticultural and economic value, and makes it highly desirable in the flower markets in China and Southeast Asia. However, little is understood about the molecular mechanism underlying leaf-color variations. In this study, we found the content of photosynthetic pigments, especially chlorophyll degradation metabolite...

The positive effect of melatonin on the function of the photosynthetic apparatus is known, but little is known about the specific mechanisms of melatonin's action in plants. The influence of melatonin on chlorophyll metabolism of 24-day-old Pisum sativum L. seedlings during paraquat (PQ)-induced oxidative stress was investigated in this study. Seeds were hydro-primed with water (H), 50 and 200 ...

I t has been demonstra ted tha t in the green leaf chlorophyll is combined with protein by t rue chemical linkage. The chlorophyll-protein compound of the spinach leaf is insoluble in water and buffer solutions, bu t can be dispersed by detergents yielding bri l l iantly clear solutions. In addition to clarifying these solutions, the detergents denature the protein and change the absorption spe...

1. The chlorophyll-protein compound of the spinach leaf has been studied in the air-driven ultracentrifuge using the Svedberg light-absorption method, and a direct-reading refractive index method. 2. When the untreated extracts are centrifuged at low speeds, the green protein sediments with a purely random spread of particle sizes confirming the fact that the protein is not in true solution. 3....

Three vegetable dyes are used for the study: anthocyanin dye from pomegranate arils extract, betalain dye from beet root extract and chlorophyll dye from tridax procumbens leaf. The anthocyanin and betalain, anthocyanin and chlorophyll, betalain and chlorophyll dyes are blended in cocktail in equal proportions, by volume. This study determines the effect of different extraction concentrations a...

Photosynthetic pigments, biochemical activities and chlorophyll a fluorescence kinetics were investigated to survey the photosynthetic characteristics of Ginkgo biloba L. during leaf growth. The content of total chlorophyll increased rapidly while the content of carotenoids changed a little. The content of ATP, the activity of O2 evolution of chloroplasts, the electron transport activities, the...

Greenhouse experiments in a completely randomized design were carried out to investigate the effects of nitroxin fertilizer (0, 1 and 2 li/ha) on morphological and physiological traits of Amaranthus retroflexus in 2013. The traits in the study included plant height, fresh and dry weight of shoots, roots, stem and leaf, Chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, anthocyanin, a...

Leaf area index (LAI) and leaf chlorophyll content (Cab) are two important indicators of vegetation growth. Due to the high-coupling spectral signals content, simultaneous retrieval LAI Cab from remotely sensed date is always challenging. In this paper, an approach for joint estimation grassland unmanned aerial vehicle (UAV) hyperspectral data was proposed. Firstly, based on a PROSAIL model, 15...

Remote sensing using airborne imaging spectroscopy (AIS) is known to retrieve fundamental optical properties of ecosystems. However, the value of these properties for predicting plant species distribution remains unclear. Here, we assess whether such data can add value to topographic variables for predicting plant distributions in French and Swiss alpine grasslands. We fitted statistical models...