Under apparently similar field conditions individual plants of Cistus creticus turn transiently red during winter, while neighbouring plants remain green. These two phenotypes provide a suitable system for comparing basic photosynthetic parameters and assessing critically two hypotheses, i.e. anthocyanins afford photoprotection and anthocyanins induce shade characteristics on otherwise exposed ...

Recent findings have shown that photosynthesis in the skin of the seed of Posidonia oceanica enhances seedling growth. The seagrass genus Posidonia is found only in two distant parts of the world, the Mediterranean Sea and southern Australia. This fact led us to question whether the acquisition of this novel mechanism in the evolution of this seagrass was a pre-adaptation prior to geological is...

The effect of acclimation to drought in seedlings of Mediterranean evergreen sclerophyll Laurus nobilis L. (laurel) was studied in semiarid field conditions. The phytohormones abscisic acid (ABA), gibberellic acid (GA 3), zeatin (Z) and indole-3-acetic acid (IAA) contents, plant water potential, photochemical efficiency, and morphological characters were determined. Seedlings were acclimated to...

The ability of three substituted quinones, 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB), 2,6-dichloro-p-benzoquinone (DCBQ), and tetramethyl-p-benzoquinone (duriquinone) to quench the excited states of chlorophyll (Chl) molecules in Photosystem I (PSI) was studied. Chl fluorescence emission measured with isolated PSI submembrane fractions was reduced following the addition of exogeno...

To explore the response of summer maize leaf senescence, photosynthetic characteristics, and yield to depth one-time base application controlled-release urea, which provides a theoretical basis for light simplified production maize. Seven treatments were set up with Zhengdan 958 as material under field conditions, including no nitrogen fertilizer (CK), surface spreading (DP0), furrow 5 cm (DP5)...

This work aims to identify the impacts of vermicompost leachate (VCL) toward its salt resistance stress in plants. Young Capsicum annuum L seedlings were subjected salinity (160 mM NaCl added a nutrient solution) over course seven days during or following adding 7 mL L−1 VCL. The exposure resulted notable decrease dry and fresh leaf weights, K+ concentrations, water content; whereas root ...

Responses of Ulva prolifera and Ulva linza to Cd(2+) stress were studied. We found that the relative growth rate (RGR), Fv/Fm, and actual photochemical efficiency of PSII (Yield) of two Ulvaspecies were decreased under Cd(2+) treatments, and these reductions were greater in U. prolifera than in U. linza. U. prolifera accumulated more cadmium than U. linza under Cd(2+) stress. While U. linza sho...

To examine the combined effects of phosphorus (P) nutrition and CO2 on photosynthesis, chlorophyll fluorescence (CF), and nutrient utilization and uptake, two controlled-environment experiments were conducted using 0.01, 0.05 and 0.20 mM external phosphate each at ambient and elevated CO2 (aCO2: 400 and eCO2: 800 mmol mol –1, respectively). The CF parameters were affected more by P nutrition th...

Temperature dependencies of stem dark respiration (R(d)) and light-driven bark photosynthesis (A(max)) of two temperate tree species (Fagus sylvatica and Betula pendula) were investigated to estimate their probable influence on stem carbon balance. Stem R(d) was found to increase exponentially with increasing temperatures, whereas A(max) levelled off or decreased at the highest temperatures cho...

In order to explore the adaptive strategies of tree peony yl1 mutant in response photooxidative stress, changes biochemical parameters, chlorophyll fluorescence, and modulated 820-nm reflection wild-type plants were compared. We found activities superoxide dismutase catalase, contents soluble protein, proline, radicals, hydrogen peroxide, malondialdehyde, relative electrical conductivity signif...