عنوان مقاله [English]
The effect of electromagnetic field and ultrasonic waves on the seed germination, seedling characteristics and essence percent of thymes investigated by using two separate factorial experiments, based on completely randomized design with three replications, at the Seed Science and Technology Laboratory of Faculty Agricultural Sciences of Islamic Azad University of Mahabad in 2017. In the first experiment, the seeds were exposed to electromagnetic field with 5, 50 and 100 milli tesla for 5, 15 and 30 minutes, and in the second experiment, the seeds were exposed to ultrasound intensity of 20, 40 and 60 kHz for 4, 8 and 12 minutes. Results of analysis of variance showed that the effects of electromagnetic field intensity by ultrasound intensity interactions were significant on all traits and indices. In this research, the highest germination percentage (97.66%), speed of germination (0.20), root length (8.70 cm), stem length (9.67 cm), root dry weight (41.5 mg), stem dry weight (44.75 mg), seedling dry weight (86.21 mg), plant dry weight (0.82g), and lowest mean germination time (4.84 days) belonged to the seeds treated with electromagnetic field intensity of 50 milli tesla for 15 minutes. The results also revealed that highest germination percentage (90.66%), germination speed (0.21), root length (7.78 cm), stem length (6.65 cm), root dry weight (41.21 mg), stem dry weight (53.60 mg), seedling dry weight (94.80 mg) and plant dry weight (0.55 g) and the lowest mean germination time (4.96 days) were related to 60 KHz ultrasound intensity for 16 minutes. The highest essence percent was produced from seeds treated with electromagnetic fields of 5 milli tesla for 30 minutes (3.44 percent) and 60 KHz ultrasound waves for 16 minutes (2.95 percent). Thus, these treatments are recommended to improve thyme germination and its seedling properties.
· Aghajani, Z., R. Ekhtiari, and A. Pourmindani. 2014. Study of the effects of silver nanoparticles on germination and early growth of mountain thymus (Thymus kotschyanus L.). Agronomic Research in Semi Desert Regions. 1(2): 73-85.
· Aladjadjiyan, A. 2010. Influence of stationary magnetic field on lentil seeds. International Agrophysics. 24: 321- 324.
· Alvandian, S., A.S. Vahedi, and R. Taghizadeh. 2013. Investigating the effect of ultrasound and chilling on germination of seeds of medicinal plant (Myrtus communis L.). Journal of Seed Research. 3: 21-31. (In Persian).
· Baser Kouchebagh, S., F. Farahvash, B. Mirshekari, F. Rahimzadeh Khoei, and H. Kazemi Arbat. 2014. Effects of physical seed priming and hydropriming on physiological and morphological characteristics, yield and harvest index in marigold (Calendula officinalis L.). Journal of Crop Ecophysiology. 7(4): 421-430. (In Persian).
· Bitarafan, N., A. Gholami, H. Abbas Dokht, M. Baradaran, and F. Khalighi Sigaroodi. 2017. Effects of vermicompost and mycorrhizal fungi on growth characteristics, essential oil and yield of thyme (Thymus vulgaris L.). Journal of Agroecology. 9 (1): 102-114.
· Das, R., and R. Bhattacharya. 2006. Impact of electromagnetic field on seed germination. Proceedings of the International Conference on Modern Electrostatics, Beijing, China. 141-145.
· Dhawi, F., J.M. Al-Khayri, and E. Hassan. 2009. Static magnetic field influence on elements composition in date palm (Phoenix dactylifera L.). Research Journal Agriculture Biological Sciences. 5: 161-166.
· Faryabi A., H. Zaremansh, M. Keshvarii, and N. Abdali. 2008. The effect of ultrasonic waves on physiologic and morphologic processes of seed germination in capsicum pepper (Capsicum annuum) and radish (Rhaphanus sativus). The 1st National Conference on Iranian Seed Science and Technology, Gorgan. (In Persian).
· Kordas, L. 2002. The effect of magnetic field on growth, development and the yield of spring wheat. Polish Journal of Environmental Studies. 11(5): 527-530.
· Li, H., and H. Ramaswamy. 2005. Osmotic dehydration. Stewart Postharvest Review. p: 22.
· Machikowa, T., T. Kulrattanarak, and S. Wonprasaid. 2013. Effects of ultrasonic treatment on germination of synthetic sunflower seeds. International Journal of Agricultural, Biosystems Science and Engineering. 7: 1-3.
· Mahdavi, B., A.M. Modares-Sanavi, and H.R. Balochi. 2008. The effect of electromagnetic fields on germination and primary growth in the seeds of annual alfalfa (Medicago sativa L.), barley (Hordeum vulgare L.), dodder (Cuscuta sp.), and barnyard grass (Echinochloa crus-galli L.). Iranian Journal of Biology. 21(3): 433-442.
· Maleki Farahani, S., A. Rezazadeh, and M. Aghighi Shahverdi. 2015. Effects of electromagnetic field and ultrasonic waves on seed germination of cumin (Cuminum cyminum L.). Iranian Journal of Seed Research. 2(1): 109-118. (In Persian).
· Marghaeizadeh, GH., M.H. Gharineh, Gh. Fathi, A.R. Abdali, and M. Farbod. 2014. Effect of ultrasound waves and magnetic field on germination, growth and yield of Carum copticum (L.) C. B. Clarke) in lab and field conditions. Iranian Journal of Medicinal and Aromatic Plants. 30(4): 560-539. (In Persian).
· Marinkovic, J., G. Jacimovic, and V. Mircov. 2008. Use of biophysical methods to improve yields and quality of agricultural science. Journal of Agricultural Science. 53: 3-15.
· Martinez, E., M.V. Carbonell, and J.M. Amaya. 2000. A static magnetic field of 125 mT stimulates the initial growth stages of barley (Hordeum vulgare L.). Electro-and Magnetobiology. 19(1): 271-277.
· Mazaheri, D., and N. Majnoun-Hosseini. 2002. An introduction to general agronomy. Tehran University Press. (In Persian).
· Mirshekari B. 2015. Physical seed treatment and their effects on seedling emergence and yield of ribwort plantain (Plantago lanceolata) in delayed sowing date. Journal of Crop Ecophysiology. 9(3): 477-490. (In Persian).
· Racuciu, M., D.E. Creanga, and C. Amoraritei. 2008. Biochemical changes induced by low frequency magnetic field exposure of vegetal organisms. Romanian Journal of Physics. 52: 601-606.
· Risca, I.M., L. Fartais, and P. Stiuca. 2007. Ultrasound effects contributions on the Norway spruce seeds germination (Picea abies (L.) Karsten). Australian Journal of Crop Sciences. 8: 87-88.
· Saki, T., M. Nasiri, N. Abdali, and S. Alinia-Fard. 2009. The Effect of ultrasonic waves on germination percentage and rate in lavender (Lavandula stoechas L.) medicinal plant. Tehran: The Scientific Conference on Industrial Development of Medicinal Plants in Iran. (In Persian).
· Sorkhi llah Lo, F. 2009. Evaluation of the effects of ultrasound and magnetic field on germination of seeds of the everlasting medicinal plant (Calendula officinalis L.) Sixth Iranian Horticultural Congress - Guilan University. 1165-1161. (In Persian).
· Vashisth, A., and S. Nagarajan. 2010. Effect on germination and early growth characteristics in sunflower (Helianthus annuus) seeds exposed to static magnetic field. Journal of Plant Physiology. 167: 149-156.
· Yaldagard, M., S.A. Mortazavi, and F. Tabatabaie. 2008. Effect of ultrasonic power on the activity of barley's alpha-amylase from post-sowing treate of seeds. World Applied Sciences Journal. 12: 34-47.