Roles of hydroxyl radical generating/scavenging mechanisms in pseudo polluted dew in reducing the foliar CO2 assimilation rate and biomass production of Japanese red pine (Pinus densiflora Sieb. et Zucc.) seedlings

A greenhouse experiment was conducted to investigate the effects of water deficit on growth and physiological parameters of Ficus benjamina and Conocarpus erectus. The results revealed that all growth parameters such as plant height, stem diameter, no. of leaves, no. of branches and chlorophyll contents significantly decreased under water deficit condition. Interestingly, although leaf, stem and total biomass production and allocation decreased significantly under water deficit, but root biomass production and allocation increased significantly. Similarly, stomatal conductance to water vapor decreased significantly and CO2 assimilation rate remained similar to control under water deficit condition. Resultantly, a significant increase in water use efficiency was evident in both species under water deficit condition. These results suggested that, in spite of a significant decrease in biomass production, young Conocarpus erectus and Ficus benjamina can tolerate water deficit which is due to sustained CO2 assimilation rate and increase in root biomass.

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Phytotoxicities of fluoranthene and phenanthrene deposited on needle surfaces of the evergreen conifer, Japanese red pine (Pinus densiflora Sieb. et Zucc.)

Environmental Pollution ◽

10.1016/j.envpol.2007.10.039 ◽

2008 ◽

Vol 154 (2) ◽

pp. 264-271 ◽

Cited By ~ 37

Author(s):

Ilemobayo Oguntimehin ◽

Nobutake Nakatani ◽

Hiroshi Sakugawa

Keyword(s):

Pinus Densiflora ◽

Red Pine ◽

Japanese Red Pine ◽

Evergreen Conifer

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Salt tolerance and regulation of gas exchange and hormonal homeostasis by auxin-priming in wheat

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2013000900004 ◽

2013 ◽

Vol 48 (9) ◽

pp. 1210-1219 ◽

Cited By ~ 5

Author(s):

Muhammad Iqbal ◽

Muhammad Ashraf

Keyword(s):

Abscisic Acid ◽

Gas Exchange ◽

Acid Concentration ◽

Spring Wheat ◽

Indoleacetic Acid ◽

Co2 Assimilation ◽

Assimilation Rate ◽

Co2 Assimilation Rate ◽

Net Co2 Assimilation Rate ◽

Net Co2 Assimilation

The objective of this work was to assess the regulatory effects of auxin-priming on gas exchange and hormonal homeostasis in spring wheat subjected to saline conditions. Seeds of MH-97 (salt-intolerant) and Inqlab-91 (salt-tolerant) cultivars were subjected to 11 priming treatments (three hormones x three concentrations + two controls) and evaluated under saline (15 dS m-1) and nonsaline (2.84 dS m-1) conditions. The priming treatments consisted of: 5.71, 8.56, and 11.42 × 10-4 mol L-1 indoleacetic acid; 4.92, 7.38, and 9.84 × 10-4 mol L-1 indolebutyric acid; 4.89, 7.34, and 9.79 × 10-4 mol L-1 tryptophan; and a control with hydroprimed seeds. A negative control with nonprimed seeds was also evaluated. All priming agents diminished the effects of salinity on endogenous abscisic acid concentration in the salt-intolerant cultivar. Grain yield was positively correlated with net CO2 assimilation rate and endogenous indoleacetic acid concentration, and it was negatively correlated with abscisic acid and free polyamine concentrations. In general, the priming treatment with tryptophan at 4.89 × 10-4 mol L-1 was the most effective in minimizing yield losses and reductions in net CO2 assimilation rate, under salt stress conditions. Hormonal homeostasis increases net CO2 assimilation rate and confers tolerance to salinity on spring wheat.

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Foliar phosphorus supply and CO2 assimilation in common bean (Phaseolus vulgaris L.) under water deficit

Brazilian Journal of Plant Physiology ◽

10.1590/s1677-04202006000300007 ◽

2006 ◽

Vol 18 (3) ◽

pp. 407-411 ◽

Cited By ~ 2

Author(s):

Mauro G. dos Santos ◽

Rafael V. Ribeiro ◽

Marcelo G. Teixeira ◽

Ricardo F. de Oliveira ◽

Carlos Pimentel

Keyword(s):

Phaseolus Vulgaris ◽

Common Bean ◽

Water Deficit ◽

Co2 Assimilation ◽

Assimilation Rate ◽

Phaseolus Vulgaris L ◽

Co2 Assimilation Rate ◽

Net Co2 Assimilation ◽

Foliar Phosphorus ◽

Regulation Of Photosynthesis

Two common bean cultivars were grown in pots under greenhouse conditions. Plants were submitted to a foliar Pi spray two days before suspending irrigation, what enhanced net CO2 assimilation rate of Ouro Negro cultivar but did not change significantly the photosynthesis of Carioca cultivar under both water deficit and rehydration periods. The results revealed that a foliar Pi spray induced an up-regulation of photosynthesis in common bean under mild water deficit, with this effect being genotype-dependent.

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