197
J. Crop Sci. Biotech. 2013 (Sep) 16 (3) : 197~200 DOI No. 10.1007/s12892-013-0017-6 RESEARCH ARTICLE
Evaluation of Genetic Diversity of Aegilops tauschii Accessions Using Morphological Characters Sajjad Mansouri1, Ali Ashraf Mehrabi1, Danial Kahrizi2,* 1 2
Department of Agronomy and Plant Breeding, Ilam University, Ilam, Iran, 6939177111 Department of Agronomy and Plant Breeding, Razi University, Kermanshah, Iran, 6715685438
Received: February 05, 2013 / Revised: April 14, 2013 / Accepted: June 07, 2013 Ⓒ Korean Society of Crop Science and Springer 2013
Abstract A collection of sixty-three accessions of Ae. tauschii belonging to different eco-geographical regions were used to evaluate its genetic diversity by 15 morphological characters. The data recorded were analyzed on all accessions using multivariate analyses. Principal component analysis (PCA) indicated that first six principal components with eigenvalues more than 1 explained 77.2% of the variability amongst accessions. Through cluster analysis according to Euclidian distance and UPGMA method, accessions divided into three groups. Knowledge of genetic diversity in Aegilops species provides different levels of information which is important in the management of germplasm resources. Key words: Ae. tauschii, genetic diversity, morphological characters, PCA
Introduction The diploid grass Aegilops tauschii Coss. [syn. Aegilops squarrosa L.] is the D-genome donor to bread wheat (Triticum aestivum L., 2n = 42, AABBDD) (Kihara 1944; McFadden and Sears 1946). This species is the most important potential donor for the improvement of cultivated wheat (Kimber and Feldman 1987). Ae. tauschii is a valuable source of genes for disease, nematode and insect resistance, and quality (Appels and Lagudah 1990; Eastwood et al. 1991; Kerber and Dyck 1969; Kihara et al. 1965; Mackie et al. 1996; Schachtman et al. 1991). Wide hybridization using wild relatives can increase genetic variability and has significant implications for wheat breeding programs (Hassani 2004; Mujeeb-Kazi et al. 1996). Almost all researchers according to Eig (1929) divided Ae. tauschii into two subspecies: the first, tauschii has cylindrical spikes and the second, strangulata has cubic spikes. It was recognized that strangulata is nearer to T. aestivum in comparison to tauschii (Pestsova et al. 2000). There are some studies of Ae. tauschii germplasm using morphological traits (Hammer 1980; Knaggs 2000; Naghavi 2005), but still there are some regions Danial Kahrizi (
) E-mail:
[email protected] Tel: +98-833-1724 / Fax:+98-831-331724
The Korean Society of Crop Science
for which little information is available for important agronomic and morphological traits of these species. In this study, 63 accessions of Ae. tauschii were used to study genetic diversity by using morphological traits.
Materials and Methods A collection of sixty-three accessions of Ae. tauschii belonging to different eco-geographical regions were used to evaluate its genetic diversity. The accessions originated from Iran, Afghanistan, Tajikistan, Azerbaijan, Armenia, Turkmenistan, and Turkey and the origins of three accessions were unknown (Fig. 1; Table 1). The experiment was carried out as an augmented design with six control accessions in order to adjust evaluated characters. Each accession was planted in 1-m-long rows with 0.5-m-row spacing during 2009 - 2010 in the experimental field of the College of Agriculture, University of Ilam. For characterization and evaluation, data were recorded following descriptors established for Aegilops (IBPGR 1981) with some modifications: plant height, number of nodes per stem, stem diameter, spike length, spike diameter, peduncle length, number of fertile
198
Genetic Diversity of Aegilops tauschii via Morphological Characters
Table 2. Descriptive statistics of accessions ssp. tauschii Trait Mean S.D. C.V. %
Fig. 1. The geographical origins of some accessions of Ae. tauschii used in this study
Table 1. Accessions and their geographic origins Subspecies Location Origin/altitude Tauschii Tauschii Tauschii Tauschii Tauschii Tauschii Tauschii Tauschii Tauschii Tauschii Tauschii Tauschii Tauschii, trangulata Tauschii, trangulata Tauschii, trangulata Tauschii, trangulata Tauschii, trangulata Strangulata Tauschii,Tauschii Tauschii
Ardebil Astara Behshahr Lahijan Gilan Chalous Mazandaran Golestan Ramsar Zanjan Harsin Dashte-moghan Iran Afghanistan Armenia Azerbaijan Tajikistan Turkemenistan Turkey Unknown
NPGBI NPGBI NPGBI NPGBI NPGBI NPGBI NPGBI -
No. of accessions 4 1 2 2 5 5 4 2 3 1 1 1 13 4 2 5 2 1 2 3
tillers, number of sterile tillers, length of awns, number of spikelets per spike, number of grains per spikelet, days to heading, days of 50% heading, biological yield, and hundredgrain weight from five plants which had been randomly chosen in each row and the mean of quantitative data sets were used for analysis. Data were analyzed by SPSS 11.0 and Minitab software.
Results and Discussion Means, standard deviations, and C.V. for the accessions are shown in Table 2. High variation was observed for many of traits (for ssp. tauschii especially). Diversity related to length of awn (57.44%) was highest and days of heading (4.1%) was lowest for ssp. strangulata. The highest diversity was related to peduncle length (76.10%) and the lowest was related to days of heading (4.38%) for ssp. tauschii. In total, the tauschii accessions had the high mean value for days of heading, spike length, and plant height. In the study carried
Plant height (cm) 32.88 Number of node per stem 4.03 Stem diameter (mm) 1.57 Spike length (mm) 59.01 Spike diameter (mm) 3.29 Peduncle length(mm) 18.17 Number of fertile tiller 16.70 Number of sterile tiller 3.02 Length of awn (mm) 4.06 Number of spikelets per spike 7.47 Number of grains per spikelets 2.08 Days of heading 161.43 Days of 50% heading 166.84 Biological yield (g) 6.43 Hundred-grain weight (g) 1.08
9.83 0.60 0.27 12.90 0.41 13.83 5.96 1.68 2.96 1.71 0.23 7.08 8.12 3.09 0.23
29.89 14.80 17.15 21.85 12.53 76.10 35.67 55.56 72.88 22.83 10.91 4.38 4.86 48.02 20.91
ssp. strangulata Mean S.D. C.V. % 33.39 4.47 1.72 55.11 4.16 17.17 13.69 3.47 4.33 6.97 2.22 164.92 170.75 7.19 1.21
6.31 0.50 0.18 6.12 0.37 8.05 4.10 1.77 2.49 0.89 0.41 5.26 6.50 2.41 0.24
18.91 11.22 10.47 11.10 8.83 46.92 29.93 50.88 57.44 12.80 18.48 3.19 3.80 33.59 20.18
out by Naghavi and Amirian (2005) on 55 accessions of Ae. tauschii, many traits showed a high level of diversity. Additionally, Zaharieva et al. (2003) investigated three species of Aegilops and found out that plant height, thousand-kernel weight, grain weight per spike and earliness have the most share in accession diversity. In principle component analysis (PCA), six first principal components with eigenvalues more than 1 explained 77.2% of the total variance (Table 3). The analysis of nine traits of Ae. tauschii by Naghavi and Amirian (2005) showed that three components accounted for 67.8% of the total variance, also principle component analysis subdivided the germplasm of Ae. tauschii into different genetic groups. The first component accounted for 23.7% of variability and was positively related with number of spikelets per spike, biological yield and spike length. The second component accounted for 19.2% variability, was positively related with days to heading, number of sterile tiller, and number of nodes per stem. The third component contributed 10.5% of total variance; it has positive relationship with spike diameter and stem diameter. Consequently choosing through each component resultTable 3. Principal components (PCS) for 15 characters in accessions of Aegilops tauschii Characters Plant height (cm) Number of node per stem Stem diameter (mm) Spike length (mm) Spike diameter (mm) Peduncle length(mm) Number of fertile tiller Number of sterile tiller Length of awn (mm) Number of spikelets per spike Number of grains per spikelets Days of heading Days of 50% heading Biological yield (g) Hundred-grain weight (g) Eigenvalue % of total variance % cumulative variance
PC1
PC2
PC3
PC4
PC5
PC6
0.332 0.07 0.056 -0.218 -0.128 -0.423 0.124 0.379 0.006 0.197 -0.321 -0.32 0.368 -0.093 0.329 -0.158 0.087 0.178 0.396 -0.063 -0.182 -0.324 0.056 -0.152 0.077 0.197 0.647 -0.028 -0.036 0.134 0.107 -0.366 0.241 -0.142 0.076 0.148 0.341 0.096 -0.283 0.268 0.276 0.293 0.124 0.416 -0.046 0.306 -0.044 -0.219 -0.196 0.057 0.285 -0.157 0.404 -0.518 0.429 -0.116 -0.157 -0.303 -0.079 -0.15 0.172 -0.145 0.32 0.247 -0.587 0.098 -0.054 0.451 0.013 -0.401 -0.071 0.246 -0.07 0.451 -0.03 -0.377 -0.031 0.326 0.405 0.143 -0.003 0.278 0.251 0.149 0.091 0.137 0.295 0.201 0.449 -0.035 3.56 2.88 1.58 1.40 1.13 1.02 23.7 19.2 10.5 9.3 7.5 6.9 23.7 42.9 53.5 62.8 70.4 77.2
JCSB 2013 (Sep) 16 (3) : 197~200
Fig. 2. Plot of the first and second principal components based on 15 characters in Ae. tauschii accessions.
ed to selection of accessions based on traits collection existed in each component. Through cluster analysis according to Euclidian distance and UPGMA method, accessions were divided into three groups (Fig. 3). The accessions of group I were higher than the others for plant height, number of nodes per stem, and biological yield. Group II was higher in peduncle length, number of fertile tillers, number of sterile tillers, days to heading, hundred-grain weight, spike diameter, and stem diameter than other groups. Group III was higher in spike length, peduncle length, number of spikelets per spike, number of grains per spikelets, and length of awn. Therefore, in breeding programs this grouping is very useful. Also, by comparison of the dendrogram (Fig. 1) and the origin of these accessions according to morphological traits, accession groups did not conform to geographical distribution. In the study of three species of Aegilops by Zaharieva et al. (2003), there was no relationship between morphological traits and geographical place of origin. Vojdani and Meybodi (1993) believe that there is no relationship between morphological diversity and ecogeographic diversity. Nevo (1988) believes that the collecting locations belong to the geographic regions so they could be grouped based on morphological diversity. Many studies showed that subdividing based on morphological diversity does not conform to genetic dividing. Studies of Ae. tauschii and detection of their genetic diversity is very helpful for us in breeding programs. The identification of genetic diversity of Ae. tauschii can help us to determine how to transport desirable traits to bread wheat. Fig. 3. Dendrogram of 63 accessions of Ae. tauschii using UPGMA method.
199
200
Genetic Diversity of Aegilops tauschii via Morphological Characters
Acknowledgements References Appels R, Lagudah ES. 1990. Manipulation of chromosomal segments from wild wheat for the improvement of bread wheat. Funct. Plant Biol. 17: 253-266 Eastwood RF, Lagudah ES, Appels R, Hannah M, Kollmorgen JF. 1991. Triticum tauschii: A novel source of resistance to cereal cyst nematode (Heterodera avenae). Aust. J. Agric. Res. 42: 69-77 Eig A. 1929. Monographisch-kritische Ubersicht der Gattung Aegilops. Verlag des Repertoriums, Dahlem bei Berlin Hammer K. 1980. Vorarbeiten zur monographischen Darstellung von Wildpflanzensortimenten: Aegilops L. Die Kulturpflanze 28: 33-180 Hassani M. 2004. Characterization of novel storage protein genes in wheat. The University of Sydney, Sydney, Ph.D. Thsis Kerber ER, Dyck PL. 1969. Inheritance in hexaploid wheat of leaf rust resistance and other characters derived from Aegilops squarrosa. Can. J. Genet. Cytol. 11: 639-647 Kihara H. 1944. Discovery of DD-analyser, one of the ancestors of Triticum vulgare. Agric. Hortic. 19: 13-14 (in Japanese) Kihara H, Yamashita K, Tanaka M. 1965. Morphological, physiological, geographical and cytological studies in Aegilops and Triticum collected in Pakistan, Afghanistan, and Iran. Results of the kyoto University Scientific Expedition to the Karakoram and Hindukush. kyoto. Japan: Kyoto University Kimber G, Feldman M. 1987. Wild Wheat. An Introduction. Special Report 353, College of Agriculture, University of Missouri, Columbia, MO Knaggs P, Ambrose M, Reader S, Miller T. 2000. Morphological characterization and evaluation of the subdivision of Aegilops tauschii Coss. Wheat Inf. Serv. 91: 15-19 Mackie AM, Sharp PJ, Lagudah ES. 1996. The nucleotide and derived amino acid sequence of a HMW glutenin gene from Triticum tauschii and comparison with those from the D genome of bread wheat. J. Cereal Sci. 24: 73-78 McFadden E, Sears E. 1946. The origin of Triticum spelta and its free-threshing hexaploid relatives. J. Hered. 37: 8189 Mujeeb-Kazi A, Rosas V, Roldan S. 1996. Conservation of the genetic variation of Triticum tauschii (Coss.) Schmalh. (Aegilops squarrosa auct. non L.) in synthetic hexaploid wheats (T. turgidum L. s.lat. x T. tauschii; 2n=6x=42, AABBDD) and its potential utilization for wheat improvement. Genet. Resour. Crop Evol. 43: 129-134 Naghavi M, Amirian R. 2005. Morphological characterization of accessions of Aegilops tauschii. Int. J. Agric. Biol. 7: 392-394
Nevo E. 1988. Genetic resources of wild emmer wheat revisited: genetic evolution, conservation and utilization. In proceedings of the Seventh International Wheat Genetics Symposium, pp 121-126. Cambridge, UK Pestsova E, Korzun V, Goncharov NP, Hammer K, Ganal MW, Röder MS. 2000. Microsatellite analysis of Aegilops tauschii germplasm. Theor. Appl. Genet. 101: 100-106 Schachtman DP, Munns R, Whitecross MI. 1991. Variation in sodium exclusion and tolerance in Triticum tauschii. Crop Sci. 31: 992-997 Vojdani P, Meybodi M. 1993. Distribution and genetic diversity of primitive bread wheat in Iran. In: Biodiversity and Wheat Improvement: Wiley, Chichester, UK Zaharieva M, Dimov A, Stankova P, David J, Monneveux P. 2003. Morphological diversity and potential interest for wheat improvement of three Aegilops L. species from Bulgaria. Genet. Resour. Crop Evol. 50: 507-517
