جستجوی مقالات مرتبط با کلیدواژه « iron deficiency » در نشریات گروه « باغبانی »

In order to evaluate the response of quince cv. Isfahan seedlings to sodium bicarbonate stress in the presence of mycorrhizal, a factorial experiment was conducted based on a completely randomized design in the presence of four levels of soil sodium bicarbonate (0, 5, 10, and 15 mM) and four levels of mycorrhizal (Rhizophagus intraradices, Funneliformis mosseae, the combination of two species and no inoculation (control)) with three replications. The results showed a significant decrease in root colonization, seedling height, leaf number, shoot dry weight, relative leaf chlorophyll content, and total leaf antioxidant capacity with increasing sodium bicarbonate concentration in the nutrient solution. In contrast, seedlings inoculated with mycorrhizal, especially R. intraradices, increased these indices compared to the control treatment. Although a significant decrease in the roots and leaves iron concentration of quince seedlings was observed with increasing the concentration of sodium bicarbonate, the use of R. intraradices significantly improved the iron content, especially at concentrations of 5 and 10 mM sodium bicarbonate. A significant increase in the concentration of phenolic compounds and the phenylalanine ammonia-lyase enzyme activity was observed in concentrations of 5 and 10 mM sodium bicarbonate by mycorrhizal treatments. In general, it can be suggested that mycorrhizal, especially R. intraradices, probably facilitates the iron uptake and increases iron content in roots and leaves of quince seedlings in the presence of different concentrations of sodium bicarbonate by affecting the synthesis of phenolic compounds.

Due to chlorosis in leaves of sour orange trees in Eram Botanical Garden of Shiraz University, in a 2-year experiment, the trunk injection of various concentrations of iron and zinc sulfate fertilizers was examined. Experiment was conducted in a randomized complete block design with six treatments and four replications during two successive years of 201 and 2013. Treatments were injections of two concentrations of iron and zinc sulfates (. and 1%) separately, a combination of iron and zinc sulfates (with the concentration of 0.5%) and distilled water as control. In each replication, the amount of 600 ml of fertilizer was injected into each tree. Two and six weeks after injection, leaf area, chlorophyll and carotenoid contents, photosynthesis rate, sugar, starch, catalase and peroxidase activities, iron and zinc contents of leaves and total soluble solid of fruits were measured. The results showed that trunk injection of 1% of iron sulfate significantly increased photosynthesis rate, chlorophyll, starch, iron contents of leaves, catalase and peroxidase activities compared to control. While combination of 0.5% of iron and zinc sulfates had the most effect on leaf area in comparison to control. Iron sulfate injection significantly increased the amount of chlorophyll and corrected the sour orange chlorosis. On the basis of the results of this experiment, trunk injection of iron sulfate at the rate of 1% had the greatest effect on removing chlorosis in sour orange leaves.

Silicon (Si) nutrition may alleviate biotic and abiotic stresses including heavy metal deficiency and toxicity in plants. Iron deficiency and toxicity are important limiting factors in growth of rice. In the present study, role of Si nutrition on alleviation of iron deficiency and toxicity was investigated in rice plants. Plants were cultivated in greenhouse in hydroponics, using Yoshida solution, under different iron treatments (0, 2, 10, 20, 50, 100 and 250 mg/L as Fe- EDTA) and Si nutrition (0 and 1.5 mM as sodium silicate). Results revealed that both iron deficiency and toxicity imposed significant reduction in fresh and dry weight and length of plants. The activity of catalase was decreased in shoots due to iron deficiency. Activity of catalase in roots and cell wall peroxidase in shoots increased under iron toxicity compared with control plants. Si nutrition increased Si content in plants and improved plant growth in both iron deficiency (not in the absence of iron) and toxicity. Application of Si increased the activity of catalase in shoots and polyphenol oxidase in both roots and shoots under iron deficiency. Also, the activity of catalase in roots and polyphenol oxidase in shoots raised following iron toxicity. This in turn may reduce the oxidative stress in plants. In addition, increase of lignin in extreme iron toxicity due to Si nutrition may enhance sites of iron absorption in plant cell walls and decrease iron toxicity. The results indicated that Si nutrition could ameliorate harmful effects of iron deficiency and toxicity in rice plants possibly through improvement of antioxidant enzyme activity and reduction of oxidative stress.