| چکیده انگلیسی مقاله |
Introduction
Iron is an essential element for plants, playing a crucial role in the structure of many oxidation and reduction enzymes and in the synthesis of chlorophyll. Its importance in nitrogen fixation and enzyme activity has been well-documented. However, in calcareous soils, such as those in Iran, non-chelated forms of iron are not effective in providing iron to plants and soil microorganisms. The use of iron chelates is considered the best solution to address iron chlorosis, particularly in alkaline soils. Excessive use of chemical fertilizers has led to the alkalinization of large agricultural areas, causing challenges such as reduced absorption of micronutrients, including iron. This experiment was designed to evaluate the effects of different particle sizes of micronutrients, including iron oxide and iron chelate nanofertilizers, on tuber quality. The potatoes used in this study were cultivated from seedlings produced through tissue culture.
Materials and Methods
A factorial experiment was conducted using a completely randomized design with three replications at the greenhouse of the Agricultural Research Institute of Hamadan during 2018–2019 and 2019–2020. The experimental factors included: microtuber weight at three levels of 1-3, 3-5 and 5-10 g and different iron fertilizers at seven levels of Zero, 20 µmol iron chelate in the form of soil consumption, 20 µmol nano iron oxide in the form of soil consumption, foliar spraying of 1% iron chelate, foliar spraying of 2% iron chelate, foliar spraying of 1% nano iron oxide and foliar spraying of 2% nano iron oxide. The iron chelate fertilizer (Fe-EDDHA 7%) was sourced from Khadra Company and is water-soluble, with plant absorption at pH levels of 3–11. Nano iron oxide with a purity of 98% was obtained from Pishgaman Nano Materials, an Iranian company. Data analysis was performed using SAS statistical software. Bartlett's test was used to check data normality, and means were compared using Duncan’s Multi-Range Test at a 5% probability level.
Results and discussion
The results of the comparison of the mean number of eyes in the microtuber under the influence of the size of the tuber and iron fertilizer showed that the lowest number of eyes per tuber (3.18 eyes) was in the absence of application of iron fertilizer in the tuber 1-3 g and the highest number of eyes in the tuber (4.24 eyes) was in the application of 20 µmol iron chelate was obtained in microtuber 10-5 g. The results indicated that the number of tuber eyes, as well as iron, protein, and amino acid contents (alanine, glycine, methionine, and lysine), increased with the weight of the microtubers. Iron fertilizers had no significant effect on protein levels in microtubers weighing 1–3 g or 3–5 g. However, in 5–10 g microtubers, the highest protein contents (4.67%, 4.81%, 5.16%, 5.4%, and 5.67%) were observed with treatments of 2% iron chelate, 1% iron chelate, 2% nano iron oxide, 20 µmol nano iron oxide, and 20 µmol iron chelate, respectively. There was no significant effect of iron fertilizers on alanine in 5–10 g microtubers. In 1–3 g microtubers, treatments with 20 µmol iron chelate, 20 µmol nano iron oxide, 1% iron chelate, and 2% nano iron oxide resulted in the greatest increases in alanine levels. In 1–3 g microtubers, iron application did not significantly differ from the control. In 3–5 g microtubers, foliar spraying with 2% iron chelate increased methionine by 17.92%. For 5–10 g microtubers, the highest methionine levels (1.32 and 1.36 µmol.g-1 FW) were observed with treatments of 20 µmol iron chelate and 2% iron chelate. The maximum lysine levels (2.19, 2.43, and 2.49 µmol.g-1 FW) were achieved with treatments of 20 µmol iron chelate, 1% nano iron oxide (foliar spray), and 20 µmol nano iron oxide, respectively, in 5–10 g microtubers.
Conclusion
Nano iron oxide fertilizers were more effective than iron chelates in enhancing tuber quality. The nanoscale size of iron particles increases the number of reactive atoms, resulting in higher reactivity and efficiency. Consequently, the application of nano iron fertilizers requires less material while achieving superior results. The highest quality improvement of potato tuber was observed in microtubers of 5-10 g and foliar application of nano iron oxide fertilizer. |