Evaluating the Relationships among Traits in Thyme (Thymus daenensis subsp. Daenensis) Ecotypes under Non-Stress and Drought Stress Conditions
Subject Areas : Journal of Crop Ecophysiology
1 - Assistant Professor, Department of Agriculture, Payame Noor University, Tehran, Iran
Keywords: factor analysis, Correlation, Path analysis, stepwise regression,
Abstract :
To study the relationships among traits of thyme ecotypes, two experiments under non-stress and drought stress conditions were carried out using randomized complete block design with four replications in Abarkouh during 2017-2018 cropping season. Correlation analysis was used for evaluation of relationships among traits. Stepwise regression and path analysis were used for determination of effective traits on shoot dry weight and for determination of direct and indirect effects on shoot dry weight, respectively. Factor analysis was used for identifying factors that produce special correlations among measured variables. Correlation coefficients among traits showed that there were significant positive correlation among traits like shoot fresh and dry weight with maximum and minimum diameter of canopy, canopy area, leaf length, number of stems per plant and essential oil yield under both conditions. The result of stepwise regression showed that canopy area, leaf width, leaf length, number of flower in inflorescence and number of days to 50% of flowering under non-stress condition and canopy area, leaf width, leaf length and number of days to 50% of flowering under stress condition were entered to the stepwise regression model. The result of path analysis under both conditions showed that canopy area had the highest direct and positive effect on shoot dry weight and leaf width and negative effect on shoot dry weight. Based on factor analysis, three factors were selected and these factors explained 76% of total variation under both conditions and traits such as shoot fresh and dry weight, maximum and minimum diameter of canopy, canopy area, leaf length, number of stems per plant and essential oil yield were main components of these factors.
· Aflakian, S., H. Zeinali, H. Maddah Arefy, Sh. Enteshary, and Sh. Kaveh. 2012. Study of yield and yield components in 11 ecotype of Thymus daenensis Celak. Iranian Journal of Medicinal and Aromatic Plants. 28(2): 187-197. (In Persian).
· Bahrami Najad, S., and A. Papzan. 2006. Effect of row spacing on different characteristics of black cumin (Nigella sativa L.) under Kermanshah conditions. Iranian Journal of Crop Sciences. 3(3): 241-249. (In Persian).
· Balandari, A. 2011. Echophysiological characteristics and cultivation aspects of dwarf chicory (Cichorium pumilum Jacq.) in Mashhad. Ph.D. Thesis, Ferdowsi University of Mashhad. (In Persian).
· Bigdeloo, M., V. Nazeri, and J. Hadian. 2013. Evaluation of morphological variations in different endemic Thymus caramanicus Jalas. species to Iran. Journal of Applied Crop Breeding. 1(2): 145- 160. (In Persian).
· Davazdahemami, S., and N. Majnoonhosini. 2008. Cultivation and production of certain herbs and species. Tehran University. 300 pp.
· Ghaderi, A.A., B. Fakheri, and N. Mahdi Nezhad. 2017. Evaluation of the morphological and physiological traits of thyme (Thymus vulgaris L.) under water deficit stress and foliar application of ascorbic acid. Crops Improvement. 19(4): 817-835. (In Persian).
· Ghasemi Pirbaloti, A., M. Samani, M. Hashemi, and H. Zeinali. 2014. Salicylic acid affects growth, essential oil and chemical composition of thyme (Thymus daenensis Celak.) under reduced irrigation. Plant Growth Regulation. 72: 289-301.
· Hadian, J., E. Karimi, M. Shouryabi, F. Nadjafi, and M.R. Kanani. 2016. Evaluation of morphological variation and path coefficient analysis of oil content of Thymus daenensis Celak populations. Plant Production Technology. 8(1): 41-56. (In Persian).
· Jamzad, Z. 2010. Thymus and Satureja spp of Iran. Research Instituted of Forests and Rangelands Press. 172 pp. (In Persian).
· Johnson, R.A., and D.W. Wichern. 2007. Applied multivariate statistical analysis. Pearson Education, Upper Saddle River. New Jersey. 773 pp.
· Majer, P., L. Sass, T. Lelley, L. Cseuz, I. Vass, D. Dudits, and J. Pauk. 2008. Testing drought tolerance of wheat by a complex stress diagnostic system installed in greenhouse. Acta Biologica Szegediensis. 52: 97-100.
· Nickavar, B., F. Mojab, and R. Dolat-Abadi. 2005. Composition of the volatile oil of Thymus daenensis Celak. subsp. daenensis.Journal of Medicinal Plants. 1(13): 45-49. (In Persian).
· Omidbaygi, R. 2009. Production and processing of medicinal plants. Astane Ghodse Razavi. First Vol. 347 pp. (In Persian).
· Parvizparashkoh, S., A. Mohamadi, and S. Mousavi. 2013. Study of morphologic diversity of 24 Thymus ecotypes. Iranian Journal of Rangelands and Forests Plant Breeding and Genetic Research. 21(2): 329-342.(In Persian).
· Razaei,M., A. Safarnejad, M. Arab, S.B.L. Alamdari, and M. Dalir. 2016. Investigation of morphologic variation and essence value in several Thyme native species (Thymus sp) of Iran. Journal of Horticulture Science. 30(3): 383-394. (In Persian).
· Rezaei, A., and A. Soltani. 2008. An introduction to applied regression analysis. Publication Center of Isfehan University. 294 pp. (In Persian).
· Sadeghzade Ahari, D., M.R. Hassandokht, A. Kashi, and A. Omri. 2017. Effect of some agronomical and physiological traits on fenugreek (Trigonella foenum-graecum) seed yield and biomass under drought condition. Journal of Applied Research of Plant Ecophysiology. 3(2): 67-84. (In Persian).
· Shoryabi, M. 2013. The domestication of Thyme daenensis: Morphological diversity, phytochemical, sustainability quantitative and qualitative characteristics and micropropagation. M.Sc. Thesis, Shahid. Beheshti University of Tehran. (In Persian).
Stahl-biskup, E. 2002. In thyme: The genus Thymus. Essential oil chemistry of the genus Thymus- A global view. Taylor and Francis London. pp. 75–124.