Introduction: Toxic soil concentrations of the essential micronutrient boron (B) represent major limitations to crop production worldwide. Plants have a range of defense systems that might be involved in their affinity to resist and tolerate nutrients stress. Materials and methods: The experiments were carried out to study the differential responses in five wheat cultivars to boron toxicity. Results: The fresh and dry matter yield of the test wheat cultivars showed marked decrease as the concentration of boron was increased. Elevated concentration of boron had a notable inhibitory effect on the biosynthesis of pigments fractions in the test wheat cultivars as severely as dry matter gain. The adverse concentration effects of boron on some metabolic responses were clearly displayed by shoot and root systems, exhibited in the elevated rates of proline, hydrogen peroxide and malondialdehyde formation. Potassium leakage was severely affected by boron-stress in some cultivars at all tested concentrations, while in some others a moderate damage was manifested only at the higher boron concentrations. Conclusions: Sakha 93 out of all the different cultivars investigated was found to display the lowest sensitivity to boron-stress, while Gemmeza 9 was the most sensitive one.

Introduction: Toxic soil concentrations of the essential micronutrient boron (B) represent major limitations to crop production worldwide. Plants have a range of defense systems that might be involved in their affinity to resist and tolerate nutrients stress. Materials and methods: The experiments were carried out to study the differential responses in five wheat cultivars to boron toxicity. Results: The fresh and dry matter yield of the test wheat cultivars showed marked decrease as the concentration of boron was increased. Elevated concentration of boron had a notable inhibitory effect on the biosynthesis of pigments fractions in the test wheat cultivars as severely as dry matter gain. The adverse concentration effects of boron on some metabolic responses were clearly displayed by shoot and root systems, exhibited in the elevated rates of proline, hydrogen peroxide and malondialdehyde formation. Potassium leakage was severely affected by boron-stress in some cultivars at all tested concentrations, while in some others a moderate damage was manifested only at the higher boron concentrations. Conclusions: Sakha 93 out of all the different cultivars investigated was found to display the lowest sensitivity to boron-stress, while Gemmeza 9 was the most sensitive one.

The filamentous non-heterocystous cyanobacterium Oscillatoria chalybea showed molecular hydrogen photoevolution under different conditions. The major part of determined hydrogen evolution would be derived from a hydrogenase system distinct from the nitrogenase. To improve the hydrogen production, different buffers, temperatures, pH values and some inorganic cofactors were studied. The results revealed that the best buffer was Tricine-KCl, the optimum temperature was 25
C, the optimum pH value was within the range 7e7.5 and the optimum concentration of nickel chloride was 50 mM that improved also the growth of O. chalybea. The influence of inorganic cofactors showed that the addition of 105 MnCl2 increases the photoevolution of molecular hydrogen

The filamentous non-heterocystous cyanobacterium Oscillatoria chalybea showed molecular hydrogen photoevolution under different conditions. The major part of determined hydrogen evolution would be derived from a hydrogenase system distinct from the nitrogenase. To improve the hydrogen production, different buffers, temperatures, pH values and some inorganic cofactors were studied. The results revealed that the best buffer was Tricine-KCl, the optimum temperature was 25
C, the optimum pH value was within the range 7e7.5 and the optimum concentration of nickel chloride was 50 mM that improved also the growth of O. chalybea. The influence of inorganic cofactors showed that the addition of 105 MnCl2 increases the photoevolution of molecular hydrogen

Treatment of plants with thiamine (Vitamin B1) has before been shown to activate plant defence against microorganisms. Here, we have studied the effects of thiamine treatments of plants on aphid reproduction and behaviour. The work was mainly carried out with bird cherry-oat aphid (Rhopalosiphum padi L.) on barley (Hordeum vulgare L.). Aphid population growth and aphid acceptance on plants grown from seeds soaked in a 150 lM thiamine solution were reduced to ca. 60% of that on control plants. R. padi life span and the total number of offspring were reduced on barley plants treated with thiamine. Healthy aphids and aphids infected with the R. padi virus were similarly affected. Spraying or addition of thiamine at 150 lM to nutrient solutions likewise resulted in reduced aphid population growth to ca. 60%, as did plant exposure to thiamine odour at 4 mM. Thiamine treatments resulted in reduced aphid population growth also when tested with grain aphid (Sitobion avenae F.) on barley and pea aphid (Acyrthosiphon pisum H.) on pea (Pisum sativum L.). There was no direct effect of thiamine on aphid reproduction or thiamine odour on aphid behaviour, as evaluated using artificial diets and by olfactometer tests, respectively. Two gene sequences regulated by salicylic acid showed higher transcript abundance and one gene sequence regulated by methyl jasmonate showed lower transcript abundance in thiamine-treated plants but not in control plants after aphid infestation. These results suggest that the aphid antibiosis and antixenosis effects may be related to priming of defence, but more studies are needed to explain the effects against aphids.

Boron (B) toxicity is an important environmental constraint that limits plant growth and crop productivity worldwide. The aim of the present study is mainly to investigate the role played by silicon (Si), calcium (Ca2+), and salicylic acid (SA) in counteracting and ameliorating of B-induced stress in canola plants at vegetative growth stage. In this context, canola plants were grown for 29 day period in soil cultures supplied with different concentrations of boron. Special emphasis was laid on the role of the applied priming agents in modifying the adverse effects of B-toxicity on the test plants. B-treated canola plants generally manifested a negligible change in superoxide anion and H2O2 formation in the test plants. At the highest B supply (100 ppm), canola leaves exhibited significant increase in MDA and SOD activity compared to absolute control. Salicylic acid treatment significantly or nonsignificantly stimulated the activity of SOD in leaves of B or non-B-treated plants. Furthermore Ca application induced significantly the specific activity of Glutathione reductase (GR) in B-treated test plants. In addition silicon treatment significantly enhanced the specific activity of GR at 25 ppm B compared to absolute control and corresponding stressed test plants. Calcium and salicylic acid treatments partially attenuated the activity of catalase (CAT) compared to the reached results displayed by B-stressed plants. The three applied priming agents significantly or non-significantly attenuated the activity of peroxidase (POD) manifested by B-stressed test plants, but generally failed to exhibit significant changes in activity of ascorbate peroxidase (APX) compared to absolute control. These responses seemed to be of beneficial and adaptive effects with awaiting more determination.

Boron (B) toxicity is an important environmental constraint that limits plant growth and crop productivity worldwide. The aim of the present study is mainly to investigate the role played by silicon (Si), calcium (Ca2+), and salicylic acid (SA) in counteracting and ameliorating of B-induced stress in canola plants at vegetative growth stage. In this context, canola plants were grown for 29 day period in soil cultures supplied with different concentrations of boron. Special emphasis was laid on the role of the applied priming agents in modifying the adverse effects of B-toxicity on the test plants. B-treated canola plants generally manifested a negligible change in superoxide anion and H2O2 formation in the test plants. At the highest B supply (100 ppm), canola leaves exhibited significant increase in MDA and SOD activity compared to absolute control. Salicylic acid treatment significantly or nonsignificantly stimulated the activity of SOD in leaves of B or non-B-treated plants. Furthermore Ca application induced significantly the specific activity of Glutathione reductase (GR) in B-treated test plants. In addition silicon treatment significantly enhanced the specific activity of GR at 25 ppm B compared to absolute control and corresponding stressed test plants. Calcium and salicylic acid treatments partially attenuated the activity of catalase (CAT) compared to the reached results displayed by B-stressed plants. The three applied priming agents significantly or non-significantly attenuated the activity of peroxidase (POD) manifested by B-stressed test plants, but generally failed to exhibit significant changes in activity of ascorbate peroxidase (APX) compared to absolute control. These responses seemed to be of beneficial and adaptive effects with awaiting more determination.

Boron (B) toxicity is an important environmental constraint that limits plant growth and crop productivity worldwide. The aim of the present study is mainly to investigate the role played by silicon (Si), calcium (Ca2+), and salicylic acid (SA) in counteracting and ameliorating of B-induced stress in canola plants at vegetative growth stage. In this context, canola plants were grown for 29 day period in soil cultures supplied with different concentrations of boron. Special emphasis was laid on the role of the applied priming agents in modifying the adverse effects of B-toxicity on the test plants. B-treated canola plants generally manifested a negligible change in superoxide anion and H2O2 formation in the test plants. At the highest B supply (100 ppm), canola leaves exhibited significant increase in MDA and SOD activity compared to absolute control. Salicylic acid treatment significantly or nonsignificantly stimulated the activity of SOD in leaves of B or non-B-treated plants. Furthermore Ca application induced significantly the specific activity of Glutathione reductase (GR) in B-treated test plants. In addition silicon treatment significantly enhanced the specific activity of GR at 25 ppm B compared to absolute control and corresponding stressed test plants. Calcium and salicylic acid treatments partially attenuated the activity of catalase (CAT) compared to the reached results displayed by B-stressed plants. The three applied priming agents significantly or non-significantly attenuated the activity of peroxidase (POD) manifested by B-stressed test plants, but generally failed to exhibit significant changes in activity of ascorbate peroxidase (APX) compared to absolute control. These responses seemed to be of beneficial and adaptive effects with awaiting more determination.

In the present work, 3D/2D porous anodic alumina (PAA) templates have been fabricated from doped aluminum films (Al-0.5wt.% Cu and Al-1.0wt.% Si) by the one-step anodization method. Furthermore, Ni nanowires array and nanowires network were synthesized by pulse electrochemical deposition using the prepared 3D/2D PAA templates. The structures and morphologies of as-prepared alumina films and Ni nanowires are characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The grown Ni nanowire on Al-0.5Cu/Al-1Si template is revealed more strength and larger surface area than grown Ni on Al-1Si template. The diameter of the nanowires is about 50-70 nm with length 3 µm. The existence of Al-0.5Cu layer on the top of Al-1Si film is increase the branching degree of pores in Al-1Si layer. The resulting 3D Ni nanowire lattice provides enhanced mechanical stability and an increased surface area, which is interesting for energy storage and many other applications which utilize large surface area.

A new series of spirothiazolidinone polymers has been accomplished by solution polycondensation of 4,12-dioxa-1,9-dithiadispiro[4.2.4.2]tetradecane-3,11-dione (3) with different aliphatic and aromatic diamines. A model compound 4 was prepared by the reaction of spiro-monomer 3 with benzyl amine and was characterized by elemental and spectral analyses. These polymers were characterized by elemental and spectral analyses. The thermal properties of these polymers were investigated by thermogravimetric analysis and differential thermal analysis measurements. The morphological properties of selected polymers 5c and 5e were tested using scanning electron microscope to study their surface morphology. The molar masses of polymers 5a, 5b, and 5d were determined by gel permeation chromatography. In addition, the anti-inflammatory activities were studied for these spiro-polymers in comparison with the model compound by determination in vivo using acute carrageenan-induced paw edema in rats.