In order to evaluate the effects of nano Zn-Fe oxide and bio fertilizer on physiological traits, antioxidant activity and yield of wheat under salinity stress, a factorial experiment was conducted based on RCBD with three replications.Treatments were included salinity in three levels (no-salt, salinity 25 and 50 mM NaCl), four bio fertilizers levels (no bio fertilizer, seed inoculation by Azotobacter, Azosperilium, Pseudomonas) and nano oxide (without nano, application of nano Zn oxide, nano Fe oxide and nano Fe-Zn oxide 1.5 g/lit). Salinty stress decreased the chlorophyll-a, chlorophyll-b, total chlorophyll, photochemical efficiency of PSII and yield of wheat, whearas electrical conductivity, soluble sugars, proline content, and the activities of Catalase (CAT), Peroxidase (POD) and Polyphenol Oxidase (PPO) enzymes increased. Similar results were observed in CAT, POD and PPO activities due to inoculation by bio fertilizers and nano oxide. Maximum of soluble sugars and proline content were observed in the highest salinity level and application of Pseudomonas. Application of nano Zn-Fe oxide increased about 17.40% from grain yield in comparision with no application of nano oxide in the highest salinity level. Generally, it was conducted that bio fertilizer and nano oxide can be used as a proper tool for increasing wheat yield under salinity condition.

Drought stress, which is one of the most serious world environmental threats to crop production, might be compensated by some free living and symbiotic soil microorganisms. The physiological response of flax plants to inoculation with two species of arbuscular mycorrhizal (AM) fungi (Funneliformis mosseae or Rhizophagus intraradices) and a phosphate solubilizing bacterium (Pseudomonas putida P13; PSB) was evaluated under different irrigation regimes (irrigation after 60, 120, and 180 mm of evaporation from Class A pan as well-watered, mild, and severe stress, respectively). A factorial (three factors) experiment was conducted for 2 years (2014-2015) based on a randomized complete block design with three replications at Urmia University, Urmia, located at North-West of Iran (37° 39' 24.82″ N44° 58' 12.42″ E). Water deficit decreased biomass, showing that flax was sensitive to drought, and AM root colonization improved the performance of the plant within irrigation levels. In all inoculated and non-inoculated control plants, leaf chlorophyll decreased with increasing irrigation intervals. Water deficit-induced oxidative damage (hydrogen peroxide, malondialdehyde, and electrolyte leakage) were significantly reduced in dual colonized plants. All enzymatic (catalase, superoxide dismutase, glutathione reductase, and ascorbate peroxidase) and non-enzymatic (glutathione, ascorbic acid, total carotenoids) antioxidants were reduced by water-limiting irrigation. Dual inoculated plants with AM plus Pseudomonas accumulated more enzymatic and non-enzymatic antioxidants than plants with bacterial or fungal inoculation singly. Dual colonized plants significantly decreased the water deficit-induced glycine betaine and proline in flax leaves. These bacterial-fungal interactions in enzymatic and non-enzymatic defense of flax plants demonstrated equal synergism with both AM fungi species. In conclusion, increased activity of enzymatic antioxidants and higher production of non-enzymatic antioxidant compounds in symbiotic association with bacteria and mycorrhiza can alleviate reactive oxygen species damage resulting in improve water stress tolerance.

Drought stress is one of the factors which influence sunflower (Helianthus annuus L.) production. Breeding for tolerance to drought stress has become a major focus. In the present investigation, combining ability, gene action and genetic analysis of several characteristics were studied in six pure lines of sunflower and their 15 hybrids. The materials were evaluated in two separate experiments using a randomized complete block design (RCBD) with three replications in two states (well-watered and water-stressed) under controlled conditions. Comparison of mean values exhibited that under water- stressed condition the average performance of sunflower genotypes were decreased for all studied traits. In well-watered condition the highest value for seed yield per plant (SY) was observed in the cross 'LR4?LR25', whereas in water-stressed condition the highest value for this trait was observed in the hybrid 'C104?LR25'. Combining ability analysis revealed that most of agronomical traits such as head diameter, number of achene per head, head weight and seed yield inherited differently in stressed and non-stressed conditions. In water-stressed conditions, the non-additive effects played a more important role for controlling the number of achene per head (NA), seed yield per plant (SY), head diameter (HD), and days from flowering to physiological maturity (DFM) than additive. Based on results yield improvement for water-stressed conditions requires selection under drought conditions. In well-watered condition, the cross 'LR4?C10' showed the best SCA value for seed yield per plant (SY). In water-stressed conditions, 'RHA266?C100' had the highest SCA for seed yield per plant (SY) and number of achene (NA) per head.

No abstract

Arbuscular mycorrhizal fungi are considered to have the potential to increase the tolerance of host plants to water-defi cit stress. Th is is due to their apparent role in water and nutrient uptake and transfer to their host plants. To evaluate the eff ects of mycorrhizal fungi species and water-defi cit stress on mung bean [Vigna radiata (L.) R. Wilczek var. radiata] plants, a 2-yr split-plot experiment based on a randomized complete block design with three replications was conducted in the fi eld in 2009 and 2010. Treatments were the application of various irrigation levels (irrigation aft er 50, 100, 150, and 200 mm of evaporation from a Class A pan as the main plot) and inoculation with two mycorrhizal fungal species (Glomus mosseae, G. intraradices, and uninoculated plants as subplots). Our results from 2 yr of experiment indicates that the highest (1833.51 and 479.15 kg ha -1 ) and lowest (1139.56 and 333.99 kg ha -1 ) seed and protein yield were obtained from plants irrigated aft er 50 and 200 mm of evaporation, respectively; however, the maximum (0.60 kg m -3 ) and minimum (0.32 kg m -3 ) ecosystem water use effi ciency was observed in plants irrigated aft er 200 and 50 mm of evaporation, respectively. Seed yield, biological yield, leaf P, leaf N, protein percentage, protein yield, harvest index of protein, and ecosystem water use effi ciency were improved in mycorrhizal plants compared with the non-mycorrhizal plants. Our results suggest that both G. mosseae and G. intraradices signifi cantly improved the yield (seed and protein) and reduced the water-defi cit stress in mung bean plants in the fi eld.