We examined the adjustment of leaf angle (L theta) and foliar chlorophyll and xanthophyll chemistry in Eucalyptus nitens (Deane and Maiden) Maiden seedlings maintained in various nitrogen (N)-supply treatments over a 6-month period. Adjustment of L theta toward the vertical was greatest under conditions of foliar N deficiency and became incrementally more horizontal with increasing foliar N con...

response of tea plants to b deficiency was studied in hydroponic medium under environmentally controlled conditions. plants height, number of leaves and dry matter production of shoot and root were significantly decreased by b deficiency. concentration of chlorophyll, carotenoids, anthocyanins and flavonoids was not affected by b deficiency in the young leaf, while a significant reduction of ch...

Response of tea plants to B deficiency was studied in hydroponic medium under environmentally controlled conditions. Plants height, number of leaves and dry matter production of shoot and root were significantly decreased by B deficiency. Concentration of chlorophyll, carotenoids, anthocyanins and flavonoids was not affected by B deficiency in the young leaf, while a significant reduction of Ch...

Although the symptoms of magnesium deficiency are well documented in plants, the primary physiological effects of low Mg availability remain largely unknown. This paper describes the physiological responses of Mg starvation in Arabidopsis thaliana. Growth characteristics, Mg and sugar concentration, and photochemical performance were measured at regular intervals during the induction of Mg defi...

Increasing atmospheric carbon dioxide (CO2) concentration could have significant implications on technologies for managing plant nutrition to sustain crop productivity in the future. Soybean ( Glycine max [L.] Merr.) (C3 species) and grain sorghum ( Sorghum bicolor [L.] Moench) (C4 species) were grown in a replicated split-plot design using open-top field chambers under ambient (357 μmol/mol) a...

A growing number of studies have focused on evaluating vegetation indices in terms of their sensitivity to vegetation biophysical parameters as well as to external factors affecting canopy reflectance. In this context, leaf and canopy radiative transfer models have provided a basis for understanding the behaviour of such indices, particularly their resistance to external perturbing effects rela...

Eight green leaf and eight red leaf lettuce varieties were grown in a greenhouse under control, receiving supplemental ultraviolet-A (UV-A) (320–400 nm) and supplemental UV-A plus ultraviolet-B (UV-B) (290–320 nm) radiation. The edible portion of the lettuce was frozen, lyophilized and extracted in 80% aqueous acetone for carotenoid and chlorophyll content determination by reverse-phase HPLC. L...

the effect of automobile pollution was determined on chlorophyll content of four different tree species viz. azadirachta indica l., conocarpus erectus l., guiacum officinale l.and eucalyptus sp. growing along the roads of the city.  significant changes in the level of chlorophyll “a”, chlorophyll “b” and total chlorophyll “a+b” were found in the leaves of four tree species (a. indica, c. erectu...

This study was conducted at Biology Department, Faculty of Science,Taif University, Saudi Arabia to investigate the effect of different salinity concentrations 8.6, 12.9, 17.2, 25.9, 34.5, 51.7, 86.2, 103.4 and 120.7 mM NaCl, beside control treatment (tap water) on growth parameters, leaf measurements and leaf chemical constituents of jojoba (Simmondsiachinensis (Link) Schneider). The results i...