Document Type : Research Paper



Background and Objectives
Seed priming is a type of pre-sowing seed treatment known to improve seed performance by increasing seed germination rate and uniformity. Another factor which could be helpful for rapid and uniform germination and emergence is seed size. Seed size is a component of seed quality which has an impact on the performance of crop. The main objective of this work was to study the effect of priming and seed size on quantitative and qualitative characteristics of two onion genotypes.
Materials and methods
In order to evaluate the effect of priming and seed size on quantitative and qualitative characteristics of onion genotypes a factorial field experiment based on a randomized complete block design with three replications was conducted in 2012 and 2013 cropping season at Agriculture and Natural Resources Research Center of  East Azarbayjan, Iran. The experimental treatments included priming (at four levels: hydro priming, osmopriming (in 2% KNO3), priming with folammin amino acid (in 2%) and control (without priming), seed size (at three levels: small, medium and large) and genotype (at two levels: Red Azarshahr and Zargan). Quantitative characteristics included bulb fresh and dry yield, bulb, leave fresh and dry weight and qualitative characteristics included percentages of soluble solids and dry matter, bulb pH, pyruvic acid content, bulb and Leave ash of onion.
Analysis of variance for the measured traits indicated that all characteristics significantly were affected by priming and seed size. Results showed that seed priming and seed size improved quantitative and qualitative characteristics of onions. The highest bulb fresh and dry yield, total soluble solids and dry matter, were obtained from plant that primed with folammin amino acid 58.17, 7.27 (tha-1), 12.54, 13.67 percent, respectively, and the lowest were achieved from control plants. Also, mean comparison indicated that the higher values of bulb fresh and dry yield, total soluble solids and dry matter were obtained from large seed size 58.99, 7.37 (tha-1), 11.14, 12.45 percent, respectively and the lower values were found to belong to small seed size. Genotypes mean comparison showed that the higher values of bulb fresh and dry yield, total soluble solids and dry matter were obtained from Red Azarshahr cultivar 53.46, 6.68 (tha-1), 12.62, 11.81 percent, respectively.
According to the results mentioned above, seed priming treatments improved quantitative and qualitative characteristics as compared to the unprimed. Among the treatments, seed priming with folammin amino acid 2 % was more effective than the potassium nitrite 2 % and hydropriming. Large seed size significantly increased the quantitative and qualitative characteristics. Accordingly, the importance of seed priming and seed grading was obvious in this study, so seed priming with folammin amino acid 2% and large seed size should be used for onion planting in order to improve quantitative and qualitative characteristics of onion. Therefore priming with folammin amino acid 2 % and large seed are recommended for onion planting for the places with the same environmental conditions.


Main Subjects

Alsadon, A. A. 2000.Yield and yield attributes of onion cultivars grown in arid regions. Horticulturae Science, 35(3): 455-472.
Baghban Sirous, Sh., Kashi, A.K., Khalighi, A., Pasban Eslam, B., and Alizadeh Oskouei, P. 2011. Inspection of some morphological and physiological traits in twelve Iranian onion population (Allium cepa L.). Journal of Plant Production, 18(1): 89-104.
Dantata, I.J., Auwalu, B.M., Machunga, N.A., Muhammad, I.A., and Babatunde, F.E. 2006. Effect of different rates of nitrogen fertilizer on the productivity and quality of Dandino tomato grown in north-eastern Nigeria. Agriculture Business and Technology Journal, 4: 49-55.
Dantata, I.J. 2014. Bulb moisture, ash and dry matter contents of onion provenances in northern Bauchi, Nigeria. Asian Journal of Applied Sciences, 2: 368-374.
Dehdari, A., Rezai, A., and Mobli, M. 2001. Morphological and agronomic characteristics of landrace varieties of onion (Allium cepa L.). Journal of Science, Technology and Natural Resource, 5(2): 109-124. [In Farsi]
Devaraju, P. J., Nagamani, S., Veere Gowda, R.m, Yogeesha, H.S., Gowda, R., Nagaraju, K., and Shashidhara, N. 2011. Effect of chemo priming on plant growth and bulb yield in onion. International Journal of Agriculture, Enviroment and Biotechnology, 4(2): 121-123.
Dhumal, K., Datir, S., and Pandey, R. 2006. Assessement of bulb pungency level in different Indian cultivars of onion (Allium cepa L.). Food Chemistry, 100: 1328-1330.
Dorna, H., Jarosz, M., Szopinska, D., Szulc, I., and Rosinska, A. 2013. Germination, vlgour and health of primed (Allium cepa L.) seeds after storage. Acta Scientiarum Polonorum Horticulture, 12(4): 43-58.
Gamiel, S. Smittle, D.A., and Mills, H.A. 1990. Onion seed size, weight, and elemental content affect germination and bulb yield. Horticultural Science, 25(5): 522-523.
Izadkhah, M., Tajbakhsh, M., and Amernia. R. 2010b. Effects of different size and age of transplanting of seedling on marketable and biological yield, harvest index and some qualitative characters of long-day and intermediate- day Onion (Allium cepa L.) cultivars. Journal of Horticulturae Science, 24(2): 203-215. [In Farsi]
Izadkhah, M., Tajbakhsh, M., and Moosavezadh S.A. 2011. Study effect of age and different size of transplanting on yield, yield copmponents and some characteristics storage on onion (Allium cepa L.). Iranian Journal of Horticulturae Science Technology, 12(1): 1-14. [In Farsi]
Izadkhah, M., Tajbakhsh, M., Zardoshty, M.R., and Hasanzadeh Goratteph, A. 2010a. Evaluation effects of different planting systems on water use efficiency,
relative water content and some plant growth parameters in onion (Allium cepa L.). Notulae Scientia Biologicae, 2(1): 88-93.
Izadkhah, M., Tajbakhsh, M., Zardoshti, M.R., Hasnzade, A., Taheri, F. Saber-Rezaie, M., Feghnabi, F., and Parvizi, S 2009. Investigation the influence of planting methods on bulb and biologic yield, harvest index and some morphological triats in onion (Allium cepa L.). Online International Journal of Agronomy and Biology, 2(4): 189-193.
Jonesa, D., Shannon, D., Junvee, F., Thippaya, F., and John, F. 2005. Plant capture of free amino acids is maximized under high soil amino acid concentrations. Soil
Biology and Biochemistry, 37: 179-181.
Khokhar, K.M. Hidayat, P., Mahmood, T., Hussain, S.I., Bhatti, M.H., and Laghari, M.H. 2002. Effect of seedling/set sizes and planting times on bulb yield and quality in onion cultivar ‘Phulkara’ during autumn season. Asian Journal of Plant Sciences, 1(6): 665-667.
Marinozzi, M., Sardella, R., Scorzoni, S., Ianni, F., Lisanti, A., and Natalini, B. 2014. Valided pungency assessment of three Italian onion (Alium cepa L.) cultivars. Journal of International Science Publications: Agriculture and Food, 2: 532-541.
Masshia, S. Motallebi, A., and Shekari, F. 2001. Effect of different sowing methods on yield and bulb chracteristics in onion (Allium cpea L.). Journal of Acta Agronomica Hungarica, 49(2): 169-174.
Mettanada, K.A. and Fordham, R. 1999. The effects of plant size and leaf number on the bulbing of tropical short - day onion cultivars (Allium cepa L.) under controlled environments in the United Kingdom and tropical field conditions in Srilanka.
Journal of Horticulturae Science Biotechnology, 74(5): 623-633.
Moosavezadh, S. A. 2006. Study geneticdiversity Iranian onion landraces using morphological and molecular, ph.D. Thesis Department of Agriculture, Tabriz
University. [In Farsi]
Spurr, C.J., Fulton, D.A., Brown, P.H., and Clark, R.J. 2002. Changes in seed yield and quality with maturity in onion (Allium cepa L., cv. ‘Early Cream Gold’). Journal of Agronomy and Crop Science, 188: 275-280.
Wien, K. C. 1999. The physiology of vegetable crops. CABI Press. New York.
67 P.
Yarnia, M. Farajzadeh, E., and Tabrizi, M. 2012. Effect of seed priming with different concentration of GA3, IAA and Kinetin on Azarshahr Onion germination and seeding growth. Journal of Basic and Applied Scientific Research, 2(3): 2657-2661.