Assessment of Tolerance of Late-Flowering Almond Cultivars to Salinity

To evaluate the tolerance to salinity in almond, this factorial experiment was conducted based on completely randomized block design with three replications in greenhouse of Agricultural and Natural Resources Research Center in East Azerbaijan province. The first factor included almond cultivars (Mangha, Nonpareil, Eskandar, Araz and Sahand), and the second factor was salinity levels (electrical conductivity of 0, 2, 4, 8 and 16 dS/m). In this experiment, the plant height, fresh and dry weight of leaves, chlorophyll index and concentration of nitrogen, sodium, potassium, chloride, calcium and magnesium were measured. The results showed that the highest plant height belonged to Eskandar and Sahand cultivars. With increasing the salinity level, nitrogen concentration of the leaves decreased. Leaves of Mangha cultivar had the highest chlorine content. Although calcium concentrations of the leaves in various salinity levels were in the same statistical group, but calcium concentration was increased in higher salinity levels. Araz cultivar had the highest concentration of magnesium in its leaves. Interaction of salinity × cultivar for phosphorus content showed that Araz cultivar produced the highest phosphorus content in its leaves at salinity level of 16 dS/m. Statistical results of sodium to potassium ratio, which is an index for resistance to salinity, showed that Araz was the most tolerant almond cultivar against salinity

Effects of the Foliar Application of Magnesium and Zinc on the Yield and Quality of Three Grape Cultivars Grown in the Calcareous Soils of Iran

A completely randomized factorial block designed experiment was carried out at Maragheh region during 2007-2008 to evaluate the effects of the foliar applications of magnesium (Mg) and zinc (Zn) on the yield and quality of three grape cultivars. Factor one included three levels of Mg (0, 0.40 and 0.80% MgSO4 x H2O); Factor two consisted of three levels of Zn (0, 0.20 and 0.40% ZnSO4.7H2O); and factor three involved three cultivars of grape (Vitis vinifera L.) namely Sahebi, Soltani and Ghezel. The foliar applications were carried out in two stages, namely, during the enlargement of flower buds and three weeks after the flower petals dropped (late spring). Yield and quality characteristics such as total soluble solids (TSS), juice, pH and acidity were determined. The statistical analyses were performed using MSTATC software and Duncan tests. The analysis of variance demonstrated that the main effects of Mg, Zn and cultivars on yield were statistically significant at 1% level; and the interactive effects of the foliar application of Mg and Zn on the yield were significant at 5% level. The highest yield was obtained with the combined foliar applications of Mg and Zn-fertilizers. Ghezel variety produced the highest yield of 47.11 tons ha-1 among the three cultivars. The main effects of Mg and Zn foliar application as well as of cultivars were significant. TSS contents were significant at 1% level. The highest pH values were obtained with the foliar application of Mg sulfate at 0.80% and Zn sulfate at 0.40%. Likewise, the main effects of foliar application of Mg and Zn were significant at 1% level in the lowering of juice acidity and K/Mg ratio. Foliar application did not decrease the K/Mg ratio to the desirable level, however in the deficient soils, foliar application was not enough. It means in additional of foliar application, soil application is also necessary for obtaining desirable grape yield and quality

Optimization of Nitrogen Fertilizer Recommendation for a New Safflower Cultivar in Eastern Azerbaijan

In order to optimized nitrogen fertilizer recommendation for a new safflower cultivar called “Padideh” an experiment was conducted in two regions of East Azerbaijan, Tikmehdash and Shabestar. Experimental design was a randomized complete blocks design arranged in factorial with three replications. The first factor was different nitrogen rates including 30, 60, 120 and 180 kg ha-1 nitrogen supplied from urea and the second factor was three times of split nitrogen application (including seed sowing, rosette and before flowering stage) at 1-0-0, 0-1-0, 1/3-1/3-1/3, 0-2/3-1/3 and 0-1/3-2/3 ratios. The results showed that, there was significant difference between the two regions in terms of studied traits so that safflower in Tikmehdash out-performed it at Shabestar. In addition, different nitrogen rates had significant effects on safflower traits. In general, increase in nitrogen rate led to increase in vegetative growth and improved yield and yield components. Furthermore, some parameters such as nitrogen agronomic efficiency, nitrogen use efficiency, nitrogen physiologic efficiency and apparent nitrogen recovery increased with increasing nitrogen application. Spliting nitrogen application showed a significant effect on some vegetative and yield related traits as well as nitrogen agronomic efficiency. Interaction between nitrogen rate and time of application was significant on plant height, seed number in capitulum, seed yield and oil yield. Safflower grain yield in Tikmehdash region using 180 kg ha-1 nitrogen and applied at rosette and prior to flowering stage was found to be greater than Shabestar

Effect of Different Ratios of Ammonium: Nitrate on Photosynthesis and Fatty Acid Composition in Canola (Brassica napus L.) under Saline Conditions

In order to investigate the effect of different ratios of ammonium: nitrate on the photosynthesis and fatty acid composition in canola (Brassica napus L.) under different levels of salinity, an experiment was conducted as a factorial based on complete randomize design at Agricultural Research Center in East Azerbaijan in 2010. The first factor was different ratios of nitrogen sources to ammonium: nitrate at four levels as 0: 100, 25: 75, 50:50 and 75: 25 and the second factor was two levels of salinity as 0 and 200 mM NaCl. Results showed that the highest fresh and dry weights, leaf area and relative water content (RWC), photosynthesis rate and potassium concentration in the leaves were obtained at ammonium: nitrate (50: 50) in non-saline condition. With increasing salinity, fresh and dry weights, leaf area, relative water content (RWC), photosynthesis and leaf potassium were significantly reduced. It seems that with increasing salinity the application of nitrogen (nitrate to ammonium) ratio of 50/50 caused less injure in crop. In treatments using high amounts of ammonium by canola, higher levels of fatty acids was obtained than feeding conditions with nitrate. The highest ratio of fatty acids was measured in saline conditions when the application of nitrate :ammonium was as 25:75

Effect of Different NO3-/NH4+ Ratios on Photosynthesis, Respiration and Antioxidant Enzymes Activity of Canola (Brassica napu L.) in Saline Condition

Abstract In order to study the effects of different N sources in different salinity levels on photosynthesis٫ respiration and antioxidant enzymes activity of canola a factorial experiment was conducted in a completely randomized design in East Azarbaijan Agricultural and Natural Resources Research Center glasshouse in 2008. The first factor was different sources of nitrogen including NO3-/NH4+ ratios (0:100, 25:75, 50:50 and 75:25) and the second factor was salinity as 0 and 200 mM NaCl. The highest fresh and dry weight, leaf area, relative water content, photosynthesis, respiration and leaf P was obtained at 50:50 NO3-/NH4+ ratio in non-saline condition. Increasing salinity decreased significantly all above characteristics. But it seems that 50:50 NO3-/NH4+ ratio decreased negative impacts of salinity injury to plant. Antioxidant enzymes activity was significantly higher in saline condition than control. The lower ratio of NO3-/NH4+ led to higher activity of these enzymes. The enzymes highest activity obtained atNO3-/NH4+ ratios as 50:50 and 25:75. It was concluded that canola can tolerate better salinity stress in presence of proper ratios of N sources. Keywords: Canola, Salinity, Glutathione reductase, Superoxide dismutase, Peroxidase, Catalase, Ascorbate peroxidas