The population acceleration and better lifestyle submit new challenges for wheat researchers to breed wheat (Triticum sativum) cultivars with upgraded yield, quality, and resistance against abiotic stresses such as drought, so exploiting all available natural relatives of cultivated wheat and introducing even sensitive ones may be a useful approach to save time and efforts. Normally, the seedling stage is highly drought vulnerable, but for sensitive cultivars, the situation is more frustrating. We examine the potentiality of two regulating hormones in the upregulation of two wheat cultivars varying in their drought susceptibility at the seedling stage comparatively evaluated by morpho-physiological traits as indicators of drought tolerance. All the studied traits revealed cultivardependent variation in response to water deficit where cv. Sids 1 was tolerant and cv. Beni-suef 5 was sensitive. Shoot/root ratio, total water content, total dry weight, chlorophyll stability, total osmotic potential, osmoregulatory components, viz., soluble carbohydrates, soluble proteins and proline, membrane damage trait in terms of LOX, antioxidant defense system enzymatically in terms of APX, CAT, POD, SOD, and total antioxidant as drought tolerance indicators were the troubling shot due to water shortage in both cultivars. The damaging impacts of water deficit on these traits were conceived for sensitive cultivar compared with the tolerant one. Exogenous application of jasmonic acid (JA) or kinetin (K) efficiently conferred drought tolerance to sensitive cultivar to withstand harsh conditions in earlier stages and to perform comparably with tolerant ones. Applied hormones prompted unequivocal inversion from a state of downregulation to upregulation regarding all drought tolerance traits via reallocation of photoassimilates to vegetative sinks, thus promoting growth, increasing the accumulation of some osmoregulation compounds and thus increased tissue vigor and regulated the activity of antioxidant enzymes as well as morphological modulation attained by the restoration of shoot/root ratio. The results would promisingly be supportive of research programs seeking to develop antidrought stress practices for sensitive wheat cultivars.

Soil salinity and sodicity (alkalinity) are serious land degradation issues worldwide that are predicted to increase in the future. The objective of the present study is to distinguish the effects of NaCl and Na 2 CO 3 salinity in two concentrations on the growth, lipoxygenase (LOX) activity, membrane integrity, total lipids, yield parameters and fatty acids (FAs) composition of seeds of sunflower cultivar Sakha 53. Plant growth, LOX activity and malondialdehyde (MDA) content were reduced by salts stresses. On the contrary, salinity and alkalinity stress induced stimulatory effects on membrane permeability, leakage of UV-metabolites from leaves and total lipids of sunflower shoots and roots. Crop yield (plant height, head diameter, seed index and number of seeds for each head) that is known as a hallmark of plant stress was decreased by increasing concentrations of NaCl and Na 2 CO 3 in the growth media. Fatty acid methyl esters (FAME) composition of salt-stressed sunflower seeds varied with different levels of NaCl and Na 2 CO 3 .

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Background Evaluation of native soil microbes is a realistic way to develop bio-agents for ecological restoration. Soil alkalinity, which has a high pH, is one of the most common concerns in dry and semi-arid climates. Alkaline soils face problems due to poor physical properties, which affect plant growth and crop production. A pot experiment was carried out to investigate the impact of native mycorrhizal fungi (AMF) on the wheat plant (Triticum aestivum L.) under two levels of alkalinity stress -T1 (37 mM NaHCO3), T2 (74 mM NaHCO3) - at two developmental stages (the vegetative and productive stages). Results Alkalinity stress significantly inhibited the germination percentage, plant biomass, photosynthetic pigments, and some nutrients (K, N, and P). Mycorrhizal inoculation improved growth parameters and productivity of wheat-stressed plants. However, lipid peroxidation was significantly lowered in mycorrhizal-inoculated plants compared to non-inoculated plants. Catalase and peroxidase were inhibited in wheat leaves and roots by alkalinity, while mycorrhiza promoted the activity of these enzymes. Conclusion The results of this study demonstrated that alkalinity stress had highly negative effects on some growth parameters of the wheat plant, while AMF inoculation attenuated these detrimental effects of alkalinity stress at two stages by reducing the pH and Na concentration and increasing the availability of P and the productivity of wheat in particular crop yield parameters.

The effects of various concentrations of different carbon sources (Na 2 CO 3 and NaHCO 3) as sodicity stress on growth parameters, CO 2 consumption rate, enzyme activity, intracellular lipid content, and fatty acid profiles of Pachycladella chodatii were studied. Generally, the total chlorophyll was increased by increasing the concentrations of Na 2 CO 3 and NaHCO 3. The biomass productivity as well consumption rate of carbon dioxide of P. chodatii reached the highest values with increasing concentrations of Na 2 CO 3 and NaHCO 3. The soluble protein content of P. chodatii was highest at the lowest Na 2 CO 3 and NaHCO 3 concentrations. The addition of different concentrations of Na 2 CO 3 and NaHCO 3 in the growth media induces lipoxygenase and superoxide dismutase specific activity. Catalase and total antioxidant enzymes were increased by supplementing the growth media with 60 and 45 mg l À1 of Na 2 CO 3 and NaHCO 3 , respectively. Hydrogenase uptake activity in P. chodatii increased gradually in all treated cultures with the time elapsed recording the maximum activity after 11 days of growth especially at 60, 45 mg l À1 of Na 2 CO 3 and NaHCO 3 respectively. Lipids content was increased at low concentration of Na 2 CO 3 (40 and 15 mg l À1) and NaHCO 3 (60, 45 mg l À1) respectively. Subsequent to algal cultivation in different concentrations of Na 2 CO 3 , the cultures were filtered and biodiesel was prepared by direct esterification of dry algal biomass. Methyl esters of palmitic, elaidic and stearic acids represented the major components while myristic, pentadecanoic and 9,12-octadecenoic acids represented a minor component of biodiesel produced from P. chodatii treated with different concentrations of Na 2 CO 3 and NaHCO 3 .

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