Quality characteristics of registered cultivars and advanced lines of durum wheats grown in different ecological regions of Turkey

(1)

Quality characteristics of registered cultivars and

advanced lines of durum wheats grown in different

ecological regions of Turkey

Mehmet A. Sakin

1

, Abdulvahit Sayaslan

2

, Oral Duzdemir

3

, and Ferhat Yuksel

4

1_{Gaziosmanpasa University, Department of Field Crops, Tokat, Turkey (e-mail: m_sakin@hotmail.com);}

2_{Karamanoglu Mehmetbey University, Department of Food Technology, Karaman, Turkey;}3_{Cankiri Karatekin}

University, Department of Biology, Cankiri, Turkey; and4Gumushane University, Department of Food Engineering,

Gumushane, Turkey.Received 19 July 2010, accepted 29 October 2010.

Sakin, M. A., Sayaslan, A., Duzdemir, O. and Yuksel, F. 2011. Quality characteristics of registered cultivars and advanced lines of durum wheats grown in different ecological regions of Turkey. Can. J. Plant Sci. 91: 26 1271. In this study, pasta-quality-associated characteristics of 25 durum wheat genotypes were investigated. Durum wheat genotypes consisted of 13 advanced experimental lines and 12 registered cultivars that were grown in three different locations of Turkey for 2 yr. Genotype, location, year and their interactions were found to be statistically significant in terms of all investigated quality characteristics. Mean quality parameters for the genotypes varied as follows: yellowberry kernel 1.76.1%, pigment content 3.678.31 mg kg1, lipoxygenase (LOX) activity 12.927.9 EU g1, protein content 10.811.8% (14% mb), gluten index (GI) 12-61, sodium dodecyl sulphate-sedimentation volume 17.328.7 mL, specific sedimentation volume 1.602.52 mL. Of the genotypes, 10 contained g-gliadin 45 and six g-gliadin 42 proteins. Except for Zenit, none of the registered cultivars and advanced experimental lines investigated in this study were able to meet simultaneously the requirements for high-quality pasta products; yet certain experimental lines prevailing in specific quality characteristics, such as Line-Gdem-2, Line-Gdem-12 and Line-20, may be used for further breeding purposes. The results of this study also imply that grain yield and quality should be taken collectively into consideration in wheat breeding programs.

Key words: Durum wheat, pasta, quality, genotype, environment, Principal component analysis

Sakin, M. A., Sayaslan, A., Duzdemir, O. et Yuksel, F. 2011. Parame`tres qualitatifs des varie´te´s homologueés et des ligneés avanceés de ble´ dur cultiveés dans diverses re´gions ećologiques de la Turquie. Can. J. Plant Sci. 91: 26 1271. Dans le cadre de cette e´tude, les chercheurs ont examine´ les parame`tres associe´s a` la qualite´ des paˆtes alimentaires de 25 geńotypes de ble´ dur. Les geńotypes consistaient en 13 ligneés avanceés et en 12 varie´te´s homologueés, cultiveés a` trois endroits de la Turquie pendant deux ans. Le geńotype, le lieu, l’anneé et leurs interactions ont une incidence statistiquement significative sur les parame`tres qualitatifs. Les parame`tres moyens varient avec le geńotype comme suit : mitadinage, 1,7 a` 6,1 %; pigmentation, 3,67 a` 8,31 mg kg1; activite´ de la lipoxygeńase, 12,9 a` 27,9 UE g1; teneur en proteínes 10,8 a` 11,8 % (14 % mb); indice de gluten (IG) 12 a` 61; volume de se´dimentation SDS, 17,3 a` 28,7 mL; volume de se´dimentation spećifique, 1,60 a` 2,52 mL. Parmi les geńotypes examine´s, 10 contenaient de la g-gliadine 45 et six de la g-gliadine 42. Outre Zenit, aucune des varie´te´s homologueés et des ligneés avanceés examineés ne re´pondait simultane´ment a` toutes les exigences lieés aux paˆtes alimentaires de haute qualite´. Pourtant, quelques ligneés expe´rimentales se de´marquaient par la pre´valence de certains parame`tres, ce qui e´tait notamment le cas des ligneés Line-Gdem-2, Line-Gdem-12 et Line-20, dont on pourrait se servir pour faire progresser l’hybridation. Les re´sultats de cette e´tude signifient aussi que les programmes d’ame´lioration du ble´ devraient tenir compte a` la fois du rendement grainier et de la qualite´ du grain.

Mots cle´s: Ble´ dur, paˆtes alimentaires, qualite´, ge´notype, environnement, ACP

Durum wheat (Triticum durum Desf.) is the most appropriate raw material for the production of high-quality pasta or macaroni products, for which color and cooking properties are two most critical quality attri-butes (Bushuk 1998; Sissons 2004). Durum wheat quality, i.e., suitability for pasta products, is mostly affected by yellowberry kernel percentage, semolina yield, protein content and quality, yellow pigment content and activities of oxidative enzymes such as lipoxygenase and polyphenol oxidase (Clarke et al 1998; Borrelli et al. 1999, 2003).

The protein content and quality characteristics of durum wheats are widely responsible for the so-called

‘‘al dente’’ pasta cooking properties, whereas yellow pigments and oxidative enzymes are responsible for the bright yellow color of pasta products (Clarke et al. 1998; Troccoli et al. 2000; Aalami et al. 2007). Durum wheat protein quality is generally assessed by Sodium dodecyl sulphate (SDS)-sedimentation and gluten index (GI) tests, whereas specific gliadin and glutenin proteins linked with gluten viscoelasticity are determined by A-PAGE and SDS-PAGE techniques (Marchylo et al.

Abbreviations: EU, unit of LOX enzyme activity; GI, gluten index; LOX, lipoxygenase; SDS, sodium dodecyl sulphate

Can. J. Plant Sci. (2011) 91: 261271 doi:10.4141/CJPS10152 261

Can. J. Plant Sci. Downloaded from pubs.aic.ca by 79.123.162.63 on 04/26/11

(2)

2001; Cubadda et al. 2007). Of the gliadin proteins, g-gliadin 45, genetically linked with HMW-2 glutenins, is highly correlated with al dente cooking characteristics of pasta, whereas g-gliadin 42, genetically linked with HMW-1 glutenins, is correlated with poor cooking characteristics (Edwards et al. 2007). It is therefore essential that durum wheat cultivars with high protein content andg-gliadin 45 be used for pasta products with high cooking quality. For the production of pasta products with bright yellow color, however, wheat cultivars that are high in yellow pigment content and low in oxidative enzymes should be utilized.

The effects of growing environment together with genotype on the pasta-making quality of durum wheats have been investigated by several groups of researchers in Turkey (Aydin et al. 1993; Kilic et al. 2005; Sozen and Yagdi 2005), who found that growing environment and year significantly influenced protein content, sedimenta-tion volume, gluten index and yellow pigment content of durum wheats, all of which are major indicators for pasta quality. It was also documented that protein con-tent and kernel vitreousness were widely influenced by the environmental conditions, whereas yellow pigment content and sedimentation volume were influenced by genotype (Nachit et al. 1995; Kilic and Yagbasanlar 2003).

Turkey is among the countries possessing suitable ecological regions for durum wheat cultivation (Sehirali and Ozgen 1987). Durum wheat production on about 1.3 million ha area of Turkey fluctuates between 2 and 4 million tons per year, which is well above the domestic demand for use in the pasta and bulgur industries. Yet pasta processors usually import durum wheats to over-come the shortcomings in wheat quality (TMO 2004, 2006, 2007; TUIK 2009). In addition to high-yielding varieties, it is important that durum wheats with high pasta-making quality be identified and/or developed. In particular, research on the specific gliadin and glutenin proteins (Yildirim et al. 2008) as well as yellow pigments and oxidative enzymes (Coskun and Ercan 2003) of durum wheats grown in Turkey is rather limited. The purpose of this study was therefore to investigate the quality characteristics of certain regis-tered cultivars and advanced experimental lines of durum wheats grown in different ecological locations of Turkey.

MATERIALS AND METHODS

A total of 25 durum wheat genotypes, 12 registered cultivars and 13 advanced experimental lines, were in-cluded in the study. Nine of the registered cultivars (Aydin-93, Firat-93, Gediz-75, Harran-95, Kiziltan-91, Zenit, Altintoprak, Mirzabey and Cesit-1252) are widely grown in different regions of Turkey, whereas three of the cultivars (Cham 1, Waha and Gidara) are inter-nationally established durum wheats. Of the 13 ad-vanced experimental lines, eight lines were obtained from ICARDA (Line-1, Line-4, Line-5, Line-7, Line-11,

Line-19, Line-20 and Line-24), three mutant lines from Gaziosmanpasa University (Line-Gdem-2-1, Line-Gdem-2 and Line-Gdem12) and two lines from Dicle University (Line-286, Line-299). The advanced experi-mental lines originated from ICARDA were previously determined to be high in grain yield and resistant to common wheat diseases (Sakin et al. 2004, 2005).

Durum wheat genotypes used in the study were grown in three different locations (Tokat-Kazova: lat. 40813?N, long. 3681?E, elevation 608 m; Diyarbakir: lat. 37830?N, long. 40837?E, eleviation 660 m; Sivas-Ulas: lat. 39849?N, long. 37803?E, elevation 1385 m) for 2 yr (20052006and 20062007) with three replications by the randomized complete block design (Duzgunes et al. 1987). The average monthly temperature, rainfall and soil characteristics of the growing locations are given in Fig. 1 and Table 1. All of the P fertilizer (506 0 kg P2O5

ha1) and half of the N fertilizer (5060 kg N ha1) were applied during sowing, while the other half of the N fertilizer (5060 kg N ha1) was applied at the Zadok’s growth stage of 25.

Yellowberry kernel percentage was determined by visual examination of a 25-g wheat sample, as described by Sakin et al. (2004). All quality measurements were carried out using wheat samples milled on a standard laboratory mill to pass through a 1.0-mm screen.

Moisture contents of the samples were determined by oven-drying at 1308C for 1 h using the American Asso-ciation of Cereal Chemists International method 4415A (AACC 2000), and all analytical results were corrected to 14% moisture basis. Protein contents of the samples were assayed using the Kjeldahl procedure (N5.7) by AACC method 4610. Gluten index (GI) and wet and dry gluten contents of the samples were determined using Glutomatic system of AACC method 3812A. Sodium dodecyl sulphate sedimentation volumes of the samples were measured by AACC method 5670. Specific sedimentation volumes were calculated by dividing the SDS-sedimentation volumes of the samples by their protein contents.

Wheat samples grown at the Tokat-Kazova location in the second year of the trials were used for the determination ofg-gliadin 42/45 banding pattern of the 25 genotypes. Theg-gliadin proteins were screened using the acidic polyacrylamide gel electrophoresis (A-PAGE) technique as described originally by Bushuk and Zillman (1978) and later modified by Khan et al. (1985) and Koksel et al. (2000). For this purpose, five kernels were randomly selected from each genotype and ground se-parately using a mortar and pestle. Each ground kernel was transferred to a 2-mL centrifuge tube contain-ing about threefold 70% aqueous ethanol, thoroughly vortexed, left at room temperature for 30 min with intermitted vortexing (10 min intervals) for protein extraction, and then centrifuged (10 000 rpm/10 min) to obtain a clear supernatant. Upon appropriate pre-treatments, the supernatants were loaded onto a precast A-PAGE system, run at 15oC for 34 h at 500 V, stained

(3)

with Coomassie Brilliant Blue R-250, and then evaluated as described by Bushuk and Zillman (1978) and Khan et al. (1985). For the identification of the gliadin proteins, Marquis wheat was used as the standard and Lira-1 and Lira-2 wheats as the controls, respectively, forg-gliadin 42 (HMW-1) andg-gliadin 45 (HMW-2) proteins.

Yellow pigment (mainly carotenoids) contents of the samples were assayed using water-saturated n-butanol extracts of the samples through spectroscopic measure-ments at 435.8 nm by AACC method 1450. Lipox-ygenase activities of the samples were determined by spectroscopic measurement of the conjugated diene Tokat 0 5 10 15 20 25 30

Oct Nov Dec Jan Feb Mar Apr May Jun Jul

Oct Nov Dec Jan Feb Mar Apr May Jun Jul Oct Nov Dec Jan Feb Mar Apr May Jun Jul

0 10 20 30 40 50 60 70 80 90 100 Diyarbakir –10 –5 0 5 10 15 20 25 30 35 Temperature (°C) Temperature (°C) 0 20 40 60 80 100 120 140 Rainfall (mm) Rainfall (mm) Sivas-Ulas –10 –5 0 5 10 15 20 25 30 Temperature (°C) 0 10 20 30 40 50 60 70 80 90 100 Rainfall (mm)

Fig. 1. The average monthly temperatures (solid bars, ﬁrst year; empty bars, second year, 8C) and rainfalls (solid line, ﬁrst year; dotted line, second year, mm) in three growing locations for 2 yr.

Table 1. Soil characteristics of three growing locations

Tokat-Kazova Diyarbakir Sivas-Ulas

First year Second year First year Second year First year Second year

Available P (as P2O5, kg d1) 7.2 10.5 1.66.8 8.0 8.2 Exchangeable K (as K2O, kg kg1d1) 45.8 56.0 8.2 72.3 38.3 58.0 CaCO3(%) 10.8 9.7 12.0 2.615.4 1.0 Organic matter (%) 3.1 1.8 1.2 1.4 2.5 1.5 pH 7.8 7.8 7.67.8 7.67.9 Total salt (%) 0.04 0.04 0.09 1.1 0.02 0.02

Soil texture Clay Clay-loam Clay-loam Loam Clay-loam Clay-loam

SAKIN ET AL. * QUALITY OF TURKISH DURUM WHEAT 263

(4)

formation upon reaction of the extracts with a linoleic acid substrate as described by Rani et al. (2001) and Aalami et al. (2007). One unit of LOX enzyme activity (EU) is described as a 1.0 unit min1 change in absorbance under the assay conditions and is reported as EU g1of milled sample.

The collected data were subjected to analysis of variance (MSTAT-C software) employing the growing year and location as the random factors and the genotypes as the fixed factor. The means were compared using the Duncan multiple comparison test (Duzgunes et al. 1987). Principal component analysis was per-formed (Canoco for Windows software) in order to determine the groupings of the genotypes by their quality characteristics.

RESULTS AND DISCUSSION Effects of Genotype and Environmental Conditions on Durum Wheat Quality

Pasta-quality-associated characteristics such as yellow-berry kernel percentage, pigment content, LOX activity, protein content, dry and wet gluten contents, GI, SDS-sedimentation and specific SDS-sedimentation volumes and g-gliadin 42/45 proteins of 25 durum wheat genotypes grown in three different locations for 2 yr were investi-gated in this work. It was determined that genotype, location, year and their interactions were all statistically significant (P B0.05 or P B0.01) in terms of all investi-gated quality characteristics (Table 2). The results of the combined analysis of variance (Table 2) showed a strong influence of the locations on the contents of protein, wet gluten and dry gluten. Genotypic effects were mainly observed for pigment content, LOX activity, GI, SDS-sedimentation and specific SDS-sedimentation volumes. Year as a factor had a slight impact on the investigated quality traits, yet it was more important than location on pigment content. These results are in agreement with the previous findings that, in addition to genotype, environmental conditions are of great importance in durum wheat quality (Bushuk 1998; Troccoli et al. 2000). The mean quality characteristics of the genotypes as varied by the growing location and year are presented in Table 3. Yellowberry kernel percentage increased in the years with lower protein content, but decreased in the years with higher protein content. The mean pigment contents of the genotypes grown in all locations in the second year were significantly higher than those of the first year (P B0.01), and the mean LOX activities did not exhibit any noticeable trend. Yellow pigment content fluctuated significantly depending on the rainfall (Fig. 1). Similarly, the mean protein contents of the genotypes grown at the Tokat-Kazova and Diyarbakir locations in the second year were significantly higher than those in the first year (PB0.01 and PB0.05, respectively), whereas the mean protein contents of the genotypes grown at the Sivas-Ulas location in the second year were significantly lower than those in the first year

(PB0.01). The higher average temperature (8.28C) in the first year than that in the second year (6.98C) in Sivas-Ulas (Fig. 1) could have elevated the protein content. The mean SDS-sedimentation volumes of the genotypes, associated with protein content and quality, were similar in Sivas-Ulas and Diyarbakir locations (P0.05), but were significantly lower in the second year at the Tokat-Kazova location (PB0.05). Specific sedimentation vo-lume, which is the ratio of SDS-sedimentation volume to protein content, reflects in the most part the protein quality of wheats (Cubadda et al. 2007). In terms of the specific sedimentation volumes, the genotypes grown in the second year of Tokat-Kazova and Diyarbakir locations were lower than those of the first year, but higher in the Sivas-Ulas location. The mean wet and dry gluten contents of the genotypes, which denote protein content and quality, varied mostly by their protein contents, whereas the mean GI values of the genotypes, which somewhat indicate the level of gluten elasticity, did not differ significantly at the Tokat-Kazova and Diyarbakir locations.

Table 3 shows that wheats grown at the Diyarbakir location had the most yellow pigment (6.16 mg kg1) and the lowest LOX activity (18.1 EU g1), whereas those grown at Tokat had the least pigment (5.09 mg kg1) and the highest LOX activity (22.5 EU g1). These findings indicate that wheats grown at Diyarbakir were more appropriate for the production of bright yellow colored pasta products than those grown in Tokat (Table 3).

The mean quality parameters of wheats grown at the Tokat, Diyarbakir and Sivas-Ulas locations varied, respectively, as follows: protein content 11.7, 10.5 and 12.2%, wet gluten content 36.2, 30.1 and 38.6%, dry gluten content 12.4, 10.3 and 13.5%, GI 30, 22 and 34%, and yellowberry kernel 3.9, 4.2 and 1.3%. Sivas had the highest level of protein, wet and dry gluten and GI, while Diyarbakir had the lowest (Table 2). The wet and dry gluten contents were reported to positively correlate with kernel protein content (Elgun et al. 2002), whereas the yellowberry kernel percentage was nega-tively correlated with protein content (Porceddu et al. 1973). The increase in the protein content of wheats grown in Sivas most likely resulted from the lower grain yields (data not shown) as a result of a shorter period of dry matter production. Williams et al. (1986) reported that durum wheat protein content correlated inversely with grain yield. Wet gluten content of wheats report-edly varied with genotype, ecological conditions and climate during the ripening period (Elgun et al. 2002). It has been well established that protein contents of durum wheats are influenced much more by environ-mental factors than by genotype (Atli et al. 1993; Nachit et al. 1995; El-Haremein et al. 1996; Kilic and Yagbasanlar 2003).

Wheats grown at Sivas-Ulas had the highest mean SDS-sedimentation volume (23.5 mL), followed by Tokat (22.1 mL) and Diyarbakir (22.0 mL) (Table 2).

(5)

Table 2. Variance analysis table for quality characteristics of 25 durum wheat genotypes grown in three locations for 2 yr with three replications

Yellowberry kernel percentage Pigment content LOX activity

Variation source df Mean square Fvalue Variation (%) Mean square Fvalue Variation (%) Mean square Fvalue Variation (%)

Year (Y) 1 387.9 62.4** 6.5 129.9 3171.7** 15.9 18.7 6.4* 0.2 Location (L) 2 377.6 60.7** 12.7 43.6 1063.3** 10.6 743.0 256.3** 14.6 Y L 2 359.4 57.8** 12.1 1.7 42.5** 0.4 179.4 61.9** 3.5 Replication (L Y) 12 14.3 2.3** 3.0 0.1 1.3 0.1 1.60.5 0.2 Genotype (G) 24 20.2 3.3** 8.2 21.9 534.1** 64.2 219.8 75.8** 52.0 G Y 24 12.4 2.0** 5.0 0.615.2** 1.8 21.2 7.3** 5.0 G L 48 12.8 2.1** 10.4 0.5 11.5** 2.8 22.2 7.7** 10.5 G Y L 48 15.1 2.4** 12.2 0.5 11.5** 2.8 12.2 4.2** 5.8 Error 288 6.2 30.1 0.04 1.4 2.9 8.2

Protein content Wet gluten Dry gluten

Variation source df Mean square Fvalue Variation (%) Mean square Fvalue Variation (%) Mean square Fvalue Variation (%)

Year (Y) 1 51.1 100.6** 5.6 768.8 136.7** 4.1 65.3 76.1** 2.8 Location (L) 2 122.2 240.4** 26.8 2931.4 521.1** 31.5 401.2 467.9** 35.6 Y L 2 109.4 215.2** 24.0 1070.4 190.3** 11.5 140.6164.0** 12.5 Replication (L Y) 12 0.5 1.1 0.8 13.9 2.5** 1.0 2.2 2.6** 1.2 Genotype (G) 24 1.4 2.8** 3.7 171.630.5** 22.1 15.4 18.0** 16.4 G Y 24 1.1 2.1** 2.8 21.9 3.9** 2.8 4.65.3** 4.9 G L 48 1.4 2.7** 7.3 37.7 6.7** 9.7 4.7 5.4** 9.9 G Y L 48 2.4 4.8** 12.9 33.3 5.9** 8.62.7 3.2** 5.8 Error 288 0.5 16.1 5.6 8.7 0.9 10.9

Gluten index Sedimentation volume Specific sedimentation volume Variation source df Mean square Fvalue Variation (%) Mean square Fvalue Variation (%) Mean square Fvalue Variation (%)

Year (Y) 1 1873.9 79.5** 1.7 28.9 29.0** 0.5 3.8 207.3** 6.3 Location (L) 2 5429.2 230.4** 10.1 110.4 111.0** 3.8 2.2 119.1** 7.3 Y L 2 1125.4 47.8** 2.1 18.0 18.1** 0.64.1 223.2** 13.6 Replication (L Y) 12 19.9 0.8 0.2 1.2 1.2 0.3 0.03 1.4 0.7 Genotype (G) 24 2311.3 98.1** 51.8 182.5 183.5** 74.4 1.2 66.2** 48.5 G Y 24 364.8 15.5** 8.2 5.9 5.9** 2.4 0.06 3.1** 2.2 G L 48 243.2 10.3** 10.9 7.8 7.9** 6.4 0.07 3.6** 5.2 G Y L 48 193.2 8.2** 8.7 8.3 8.3** 6.7 0.09 5.0** 7.4 Error 288 23.66.3 1.0 4.9 0.02 8.8

*, ** Significant at P B0.05 and PB0.01, respectively.

(6)

Wheats grown at Sivas-Ulas were more likely subjected to drought stress because of the lower rainfall and higher temperature in their generative stages. Kun (1994) reported that arid conditions during the gen-erative period of wheat induced somewhat higher quality. Besides, Nachit et al. (1995) reported that SDS-sedimentation volume was influenced much more by environmental factors than by genotype.

To summarize, pasta quality characteristics of the genotypes showed remarkable variations according to the growing location and year (Table 3). Other research-ers (Borrelli et al 1999; Sozen and Yagdi 2005) also reported that pigment content, sedimentation volume, protein and wet gluten contents varied with growing location and year in durum wheats. El-Haremein et al. (1996) reported similar findings to the results of the current study, that pigment content, protein content and sedimentation volume in durum wheats increased as the rainfall decreased.

Pigment Content and LOX Activity of Genotypes Associated with Bright Yellow Color of Pasta Products

The color of pasta products is mainly influenced by the yellow pigment content and LOX activity of durum wheats (Aalami et al. 2007). For the production of bright yellow pasta products, durum wheats with high pigment content (mainly yellow carotenoids) and low LOX activity are required. Yellow pigment contents and LOX activities of 25 durum wheats grown in different locations are listed in Table 4. The pigment contents of the genotypes ranged from 3.67 to 8.31 mg kg1with a

mean value of 5.64 mg kg1, which is largely controlled by the genotype (Table 2). It is generally accepted that pigment contents of durum wheats fluctuate from 4 to 8 mg kg1 (Koksel et al. 2000). The cultivar Zenit, a well-known high-pigment cultivar of Italian origin (Landi 1995), demonstrated the highest pigment content (8.31 mg kg1) in this study. Among the experimental lines, Line-Gdem-2, Line-Gdem-12 and Line-1 prevailed in terms of pigment contents. The majority of the registered cultivars had higher levels of pigment than the overall mean (5.64 mg kg1) of the genotypes; specifically Kiziltan-91 with 7.15 mg kg1 pig-ment content was the prominent durum wheat cultivar (Table 4). In terms of the LOX activities, which cause oxidative degradation of yellow colored carotenoid pigments leading to color bleaching during semolina and pasta processing (Borrelli et al. 1999; Troccoli et al. 2000; Aalami et al. 2007), the genotypes produced values ranging from 12.9 to 27.9 EU g1with a mean value of 20.4 EU g1 (Table 4). Genotypic effects explained 52.0% of the variation, indicating that LOX activities of wheats were greatly affected by genotype (Table 2). Among the experimental lines in this work, Line-299, Line-Gdem-12, Line-286, Line-4, Line-5 and Line-7 were determined to have lower LOX activities than the mean LOX activity of the genotypes. It was reported by other researchers that durum wheat genotypes grown in Turkey (Coskun 2001) and India (Aalami et al. 2007) exhibited large variations in pigment contents and LOX activities. When judged by pigment contents and LOX activities, Line-Gdem-12 shows the greatest potential among the experimental lines studied.

Table 3. Mean quality characteristics of 25 durum wheat genotypesz

Tokat-Kazova Diyarbakir Sivas-Ulas Overall Mean

Characteristic First year Second year Second year First year First year Second year First year Second year

Yellowberry kernel percentage (%) 4.4a** 3.3b 6.8a* 1.5b 0.9b 1.7a** 4.0a** 2.2b

Pigment content (mg kg1) 4.66b 5.52a** 5.52b 6.81a** 5.15b 6.21a** 5.11b 6.18a**

LOX activity (EU g1₎ _21.1b _23.9a** _18.8a** _17.4b _{20.8 NS}x _20.620.2b _20.6a*

Protein content (%) 11.1b 12.4a** 9.5b 11.5a* 12.8a** 11.6b 11.1b 11.8a**

Wet gluten content (%) 34.3b 38.1a* 26.4b 33.7a* 40.2a** 37.0b 33.7b 36.3a**

Dry gluten content (%) 11.8 NS 13.0 9.1b 11.5a* 14.2a** 12.8b 11.7b 12.5a**

Gluten index 30 NS 30 23 NS 21 39a** 29b 31a** 27b

SDS-sedimentation volume (mL) 22.8a* 21.5b 22.1 NS 21.8 23.5 NS 23.622.8a** 22.2b

Specific sedimentation volume (mL) 2.06a** 1.74b 2.34a** 1.91b 1.85b 2.04a** 2.08a** 1.90b Location meansy

Yellowberry kernel percentage (%) 3.9a 4.2a 1.3b

Pigment content (mg/kg) 5.09c 6.16a 5.68b

LOX activity (EU g1₎ _22.5a _18.1c _20.7b

Protein content (%) 11.7b 10.5c 12.2a

Wet gluten content (%) 36.2b 30.1c 38.6a

Dry gluten content (%) 12.4b 10.3c 13.5a

Gluten index 30b 22c 34a

SDS-sedimentation volume (mL) 22.1b 22.0b 23.5a

Specific sedimentation volume (mL) 1.90c 2.13a 1.94b

z

Different letters in the same line within a column indicate *, ** significant difference at P B0.01 and PB0.05, respectively.

y

Different letters in the same line indicate significant difference (P B0.01).

x

NS, P 0.05.

(7)

Protein Content and Quality of Genotypes Associated with Proper Cooking Characteristics of Pasta Products

Protein content and quality of durum wheats are of vital importance to the al dente cooking characteristics of pasta products (Bushuk 1998; Troccoli et al. 2000). Protein contents of 25 genotypes used in this study ranged from 10.8 to 11.8% on a 14% moisture basis (Table 5), which is somewhat lower than the generally acknowledged values (Boyacioglu and Tulbek 2002). Other researchers (Sozen and Yagdi 2005) also reported similar protein contents for durum wheats grown in Turkey. In this study, protein contents of wheats were markedly influenced by location (26.8%) and year location interaction (24.0%) (Table 2). It has been well established that protein contents of wheats differ by both genotype and environment; yet environmental factors are more dominant in protein accumulation (Nachit et al 1995; Bushuk 1998; Troccoli et al 2000).

The viscoelastic and cohesive nature of gluten pro-teins, i.e., protein quality, is to a large extent genetically controlled (Veraverbeke and Delcour 2002). Durum wheat protein quality is generally assessed by SDS-sedimentation and GI tests, whereas specific gliadin and glutenin proteins associated with gluten viscoelasti-city are determined by A-PAGE and SDS-PAGE techniques (Marchylo et al. 2001; Cubadda et al 2007). Protein quality indicators of the genotypes are listed in

Table 5. The GI values of the genotypes ranged from 12 to 61 with a mean value of 29. In terms of SDS-sedimentation and specific SDS-sedimentation volumes, the genotypes displayed values varying from 17.3 to 28.7 mL and from 1.60 to 2.52 mL, respectively. Impiglia et al. (1995) reported sedimentation volumes of 18.238.5 mL and specific sedimentation volumes of 1.392.98 mL for a set of durum wheats. Sozen and Yagdi (2005) reported SDS-sedimentation volumes of 19.531.3 mL for durum wheats grown in Turkey. Koyuncu (2009) reported a SDS-sedimentation volume of 27.3 mL and a GI value of 65 for the high-cooking-quality Canadian cultivar Kyle (Dexter 2008) grown at Tokat-Kazova. In this study, Line-20, Gediz-75, Zenit, Cesit-1252, Altintoprak and Gidara genotypes demonstrated SDS-sedimentation vo-lumes (25.428.7 mL) comparable with that of Kyle (27.3 mL). Additionally, Line-20, Zenit and Gediz-75 geno-types produced GI values (4961) quite close to that of Kyle (65). With few exceptions, specific sedimentation volumes and GI values of the genotypes were closely associated (Table 5). Similar connections were also observed in durum wheats by Pena (2000) and Cubadda et al (2007).

The genotypes were screened for theg-gliadin 42 and g-gliadin 45 proteins by A-PAGE as shown in Fig. 2, and the results are listed in Table 5. Of the 25 geno-types, 10 possessedg-gliadin 45 protein associated with improved pasta cooking quality, whereas six genotypes

Table 4. Mean quality characteristics associated with pasta color quality of 25 durum wheat genotypesz

Genotype Yellowberry kernel percentage (%) Pigment content (mg kg1₎ _{LOX activity (EU g}1₎

Line-4 4.9ab 5.37hi 18.6ij

Line-11 2.7b-e 5.27ijk 25.5b

Line-24 2.3cde 3.67p 27.9a

Line-1 2.1cde 5.86g 25.3b Line-2863.1b-e 5.54h 16.8kl Line-7 1.9de 4.68m 17.5jk Line-19 3.1b-e 4.52mn 20.8fgh Line-299 2.3cde 4.59m 12.9m Line-20 3.7a-e 5.13jkl 22.4c-f

Line-5 4.0a-e 5.10kl 19.8ghi

Gediz-75 2.8b-e 5.37hi 15.5l

Aydin-93 2.0de 6.39de 21.0fgh

Zenit 2.0de 8.31a 21.1efg

Firat-93 3.4b-e 4.98l 20.2ghi

Harran-95 3.3b-e 6.07f 22.9cd

Altintoprak 4.3a-d 6.49d 16.6kl

Cham 1 3.4b-e 6.24ef 18.6ij

Waha 2.3cde 6.24ef 18.9ij

Gidara 2.7b-e 4.38n 22.2c-f

Line-Gdem-2-1 4.6abc 4.11o 22.8cd

Line-Gdem-2 6.1a 7.64b 23.8c

Line-Gdem-12 2.5b-e 6.33de 15.9l

Kiziltan-91 2.8b-e 7.15c 22.7cde

Mirzabey 3.2b-e 6.38de 21.9def

Cesit-1252 1.7e 5.29ij 19.5hi

Range 1.76.1 3.678.31 12.927.9

Mean 3.1 5.64 20.4

z

Different letters in the same column indicate significant difference (P B0.01).

(8)

Table 5. Mean quality characteristics associated with pasta cooking quality of 25 durum wheat genotypesz

Genotype Protein content (%)

Wet gluten content (%)

Dry gluten

content (%) Gluten index

SDS-sedim. volume (mL)

Specific sedimentation

volume (mL) g-Gliadin type (g-42 or g-45)

Line-4 10.8d 26.7k 9.5j 25f-j 17.4l 1.65jk Physically mixed or still heterozygous

Line-11 11.4a-d 35.4c-f 12.0c-f 23h-k 22.2fg 1.96de Physically mixed or still heterozygous

Line-24 11.4a-d 38.8a 12.8a-d 30ef 21.1hi 1.88efg g-45

Line-1 11.5abc 37.3a-d 12.9abc 26f-i 20.0jk 1.76g-j g-45

Line-28611.3a-d 34.6efg 11.8efg 17l 22.9ef 2.05d Physically mixed or still heterozygous

Line-7 11.7ab 38.2ab 13.2a 23h-k 23.0ef 2.01d g-45

Line-19 11.4a-d 35.2c-f 12.1c-f 20kl 21.1hi 1.87e-h Physically mixed or still heterozygous Line-299 11.0bcd 33.9fgh 11.5f-i 30ef 23.8e 2.17c Physically mixed or still heterozygous Line-20 11.4a-d 30.9ij 10.8i 61a 28.7a 2.52a Physically mixed or still heterozygous

Line-5 10.9cd 29.9j 10.9hi 26f-i 17.3l 1.60k g-42

Gediz-75 11.8a 35.1def 12.1c-f 49b 27.6b 2.36b g-45

Aydin-93 11.5abc 38.1ab 13.3a 21i-l 21.2hi 1.87e-h g-45

Zenit 11.6abc 33.8fgh 11.8e-h 50b 28.5a 2.45ab g-45

Firat-93 11.6abc 37.3a-d 13.1ab 24g-k 20.7ij 1.81ghi g-45

Harran-95 11.5abc 36.4b-e 12.4a-f 33de 22.9f 2.04d Physically mixed or still heterozygous

Altintoprak 11.6abc 35.3c-f 12.2b-f 39c 25.4d 2.18c g-45

Cham 1 11.4a-d 36.3b-e 12.7a-e 22i-k 19.7k 1.74hij g-42

Waha 11.8a 37.6abc 13.1ab 23h-k 21.1hi 1.81ghi Physically mixed or still heterozygous

Gidara 11.1a-d 32.5ghi 11.1ghi 27fgh 26.3c 2.38b g-45

Line-Gdem-2-1 11.4a-d 33.8fgh 11.9d-g 28fg 21.2hi 1.88efg g-42

Line-Gdem-2 11.2a-d 31.7hij 11.0ghi 12m 20.3ijk 1.82f-i g-42

Line-Gdem-12 11.7ab 37.2a-d 12.7a-e 21i-l 21.9gh 1.87e-h Physically mixed or still heterozygous

Kiziltan-91 11.8a 37.2a-d 12.4a-f 17l 22.4fg 1.94def g-42

Mirzabey 11.3a-d 31.3ij 11.6f-i 37cd 19.6k 1.73ij g-45

Cesit-1252 11.7ab 39.3a 13.2a 34d 27.4b 2.36b g-42

Range 10.811.8 26.739.3 9.513.3 1261 17.328.7 1.602.52

Mean 11.5 35.0 12.1 29 22.5 1.99

z

Different letters in the same column indicate significant difference (PB 0.01).

CANADIAN

JOURNAL

OF

PLANT

SCIENCE

(9)

contained g-gliadin 42 protein linked with poor pasta cooking characteristics. On the other hand, nine of the genotypes were found to be either physically mixed or still heterozygous. In Table 6, the relationship between theg-gliadin type and quality parameters are presented. Although mean protein contents of the genotypes with g-gliadin 42 and 45 were quite similar (11.4% vs. 11.5%), the genotypes with g-gliadin 45 demonstrated higher specific sedimentation volume (2.04 mL vs. 1.89 mL) and GI values (33 vs. 23). These results are in agreement with the previous findings that durum wheats carrying the g-gliadin 45 protein were better suited for pasta products with superior cooking quality (Edwards et al. 2007).

Principal Component Analysis of Genotypes by Quality Characteristics

In order to better understand the quality differences among the genotypes, PCA was performed (Table 7 and Fig. 3). SDS-sedimentation and specific sedimentation volumes along with GI were established as the first principal component explaining about 50.2% of the variation in quality of the genotypes (Table 7). Kernel vitreousness and wet and dry gluten contents prevailed as the second principal component and explained about 23.1% of the observed variation. Yellow pigment content and LOX activity constituted about 10.6% of the variation as the third principal component. In addition, a negative relationship between protein

content and yellowberry kernel percentage was observed (Table 7 and Fig. 3). Rharrabti et al. (2003) determined the changes in quality traits of 10 durum wheat genotypes due mainly to differences in climatic condi-tions among different zones in Spain by using PCA. When analyzed (Fig 4), Genotypes of Gediz-75 (11), Altintoprak (16), line-20 (9) and Zenit (13) had high values (Table 4) with respect to GI, SDS-sedimentation and specific sedimentation volumes traits that contrib-uted variation in first component.

CONCLUSIONS

It is evident from this study that genotype and growing environment are of vital importance in pasta-quality-associated characteristics of durum wheats, as the genotype, growing environment and their interactions were all found to be statistically significant (P B0.05 or P B0.01). Except for the cultivar Zenit, none of the registered cultivars and advanced experimental lines investigated in this study were able to meet the required criteria simultaneously for high-quality pasta proces-sing; yet, certain experimental lines prevailing in specific quality characteristics may be used for further breeding

Table 6. Relationship betweeng-gliadin type and protein quality of 25 durum wheat genotypes

g-Gliadin type Mean protein content (%) Mean specific sedimentation volume (mL) Mean gluten index g-Gliadin 45 (n 10) 11.5 2.04 33 g-Gliadin 42 (n 6) 11.4 1.89 23

Table 7. Principal component analysis by quality characteristics of 25 durum wheat genotypes

Characteristic PC1 PC2 PC3

Yellowberry kernel percentage 0.3521 0.9227 0.0457

Pigment content 0.1031 0.0384 0.6295

LOX activity 0.1439 0.0851 0.7832

Protein content 0.2578 0.5320 0.2113

Wet gluten content 0.0031 0.7956 0.0713 Dry gluten content 0.0100 0.7548 0.0509

Gluten index 0.9780 0.1894 0.0343

SDS-sedimentation volume 0.6955 0.2184 0.2203 Specific sedimentation volume 0.7004 0.1444 0.1902 Proportion of total variance (%) 50.2 23.1 10.6

Cumulative variance (%) 50.2 73.3 83.9

Fig. 2. A typical A-PAGE screening result for g-gliadin 42/45 proteins of several wheat genotypes (Std: standard; m: Marquis; l1: Lira-1 (g-gliadin 42); l2: Lira-2 (g-gliadin 45).

(10)

purposes. Of the 25 durum wheat genotypes; Zenit, Kiziltan-91, Line-Gdem-2 and Line-Gdem-12 prevailed in pasta color quality associated characteristics, whereas Line-20, Zenit and Gediz-75 in pasta cooking quality associated characteristics. These results also imply that grain yield and quality should be taken collectively into consideration in wheat breeding programs.

ACKNOWLEDGEMENTS

This work was ﬁnancially supported by the Scientiﬁc and Technological Research Council of Turkey TUBITAK (Project No. 107O644).

Aalami, M., Leelavathi, K. and Rao, U. J. S. P. 2007. Spaghetti making potential of Indian durum wheat varieties in relation to their protein, yellow pigment and enzyme contents. Food Chem. 100: 12431248.

American Association of Cereal Chemists International. 2000. AACC approved methods. 10th ed. AACC, St. Paul, MN. Atli, A., Kocak, N. and Aktan, B. 1993. Evaluation of environmental conditions in Turkey for suitability of high quality durum wheat production. The symposium of durum wheat and its products, 30 Nov03 Dec, Ankara, Turkey. pp. 345351 [in Turkish].

Aydin, F., Kocak, A. N. and Dag, A. 1993. A research on determination of burghul quality of some durum wheat varieties. The symposium of durum wheat and its products, 30 Nov03 Dec, Ankara, Turkey. pp. 310317 [in Turkish]. Borrelli, G. M., De Leonardis, A. M., Fares, C., Platani, C. and Di Fonzo, N. 2003. Effects of modiﬁed processing conditions on oxidative properties of semolina dough and pasta. Cereal Chem. 80: 225231.

Borrelli, G. M., Troccoli, A., Di Fonzo, N. and Fares, C. 1999. Durum wheat lipoxygenase activity and other quality para-meters that affect pasta color. Cereal Chem. 76: 335340. Boyacioglu, M. H. and Tulbek, M. C. 2002. A view durum wheat quality. Cereal 2002-Technology of Cereal Products Congress and Gallery, 0304 Semptember 2002, Gaziantep [in Turkish].

Bushuk, W. 1998. Wheat breeding for end-product use. Euphytica 100: 137145.

Bushuk, W. and Zillman, R. R. 1978. Wheat cultivar identiﬁca-tion by gliadin electrophoregrams. I. Apparatus, method and nomenclature. Can. J. Plant Sci. 58: 505515.

Clarke, J. M., Marchylo, B. A., Kovacs, M. I. P., Noll, J. S., McCaig, T. N. and Howes, N. K. 1998. Breeding durum wheat for pasta quality in Canada. Wheat: Prospects for Global Improvement. Springer, New York, NY. pp. 229236. Coskun, E. 2001. Determination of lipoxygenase activity in durum wheats. M.Sc. thesis. Ankara University, Graduate School of Natural and Applied Sciences, Department of Food Engineering, Ankara, Turkey.

Coskun, E. and Ercan, R. 2003. Determination of lipoxygenase activity in durum wheats. Food 28: 221226[in Turkish]. Cubadda, R. E., Carcea, M., Marconi, E. and Trivisonno, M. C. 2007. Inﬂuence of protein content on durum wheat gluten strength determined by the SDS sedimentation test and by other methods. Cereal Foods World 52: 273277.

Dexter, J. E. 2008. The history of durum wheat breeding in Canada and summaries of recent research at the Canadian Grain Commission on factors associated with durum wheat processing. Bosphorus 2008-ICC International Conference, 2008 Apr. 2426. Istanbul, Turkey.

Duzgunes, O., Kesici, T., Kavuncu, O. and Gurbuz, F. 1987. Methods of research and experiment (statistics methods II), Ankara University, Agricultural Faculty, Ankara, Turkey. No. 1021, p. 381. –1.5 1.0 –1.0 1.0 PIGM LOX PROT WET DRY GI SDS SDSi YBK 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

Fig. 3. Varimax rotated principal component loadings by quality characteristics of 25 genotypes (1(Line-4), 2 (Line-11), 3 (Line-24), 4 (Line-1), 5 (Line-286), 6 (Line-7), 7 (Line-19), 8 (Line-299), 9 (Line-20), 10 (Line-5), 11 (Gediz-75), 12 (AydIn-93), 13 (Zenit), 14 (Firat-93), 15 (Harran-95), 16(Altintoprak), 17 (Cham 1), 18 (Waha), 19 (Gidara), 20 (Line-Gdem-2-1), 21 (Line-Gdem-2), 22 (Line-Gdem-12), 23 (Kiziltan-91), 24 (Mirzabey), 25 (Cesit-1252)) (YBK: yellowberry kernel percentage; PIGM: pigment content; LOX: lipoxygenase activity; PROT: protein content; WET: wet gluten content; DRY: dry gluten content; GI: gluten index; SDS: sedimentation volume; SDSi: speciﬁc sedimentation volume).

(11)

Edwards, N. M., Gianibelli, M. C., McCaig, T. N., Clarke J. M., Ames, N. P., Larroque, O. R. and Dexter, J. E. 2007. Relationship between dough strength, polymeric protein quantity and composition for diverse durum wheat genotypes. J. Cereal Sci. 45: 140149.

Elgun, A., Ertugay, Z., Certel, M. and Kotancilar, H.G. 2002. Guide of analytical quality control and laboratory practices in cereals and their products. 3rd ed. No. 335. Atatu¨rk University Agricultural Faculty, Erzurum, Turkey.

El-Haremein, F. J., El-Saleh, A. and Nachit, M. M. 1996. Environmental effect on durum wheat grain quality in Syria. 10th. International Cereal and Bread Congress, Jun. 0912, Porto Carras, Greece.

Impiglia, A., Nachit, M. M., Laﬁandra, D. and Porceddu, E. 1995. Effect of gliadin and glutenin components on gluten components on gluten strength in durum wheat, CIHEAM-IAMZ, Zaragoza, Spain. pp. 167172.

Khan, K., Hamada, A. S. and Patek, J. 1985. Polyacrylamide gel electrophoresis for wheat variety identiﬁcation: Effect of variables on gel properties. Cereal Chem. 62: 310313. Kilic, H. and Yagbasanlar, T. 2003. Studies on determination the genotype environment interaction of durum wheat (Triticum turgidum ssp. durum) for some quality traits in the southeastern Anatolian conditions. 5th Field Crops Congress in Turkey, 1317 October, Diyarbakir, Turkey. pp. 180185.

Kilic, H., Erdemci, I., Karahan, T., Aktas, H., Karahan, H. and Kendal, E. 2005. Determination of adaptation capability of some durum wheat cultivars in the southeastern Anatolian conditions. GAP IV. Agricultural Congress, Sep. 2123, Sanliurfa, Turkey. pp. 768773.

Koksel, H., Sivri, D., Ozboy, O., Basman, A. and Karacan, H. 2000. Cereal laboratory handbook. Hacettepe University, Engineering Faculty, Ankara, Turkey.

Koyuncu, M. 2009. Screening of durum wheat landraces for selected traits associated with pasta quality. M. Sc. thesis. Gaziosmanpasa University, Graduate School of Natural and Applied Sciences, Department of Food Engineering. Tokat, Turkey. p. 49.

Kun, E. 1994. Cereal-I, Ankara University Agricultural Faculty. Ankara, Turkey. No. 1451, p. 322.

Landi, A. 1995. Durum wheat, semolina and pasta quality characteristics for an Italian food company, CIHEAM-IAMZ, Zaragoza, Spain. pp. 3342.

Marchylo, B. A., Dexter, J. E., Clarke, F. R., Clarke, J. M. and Preston, K. R. 2001. Relationship among bread-making quality, gluten strength, physical dough properties, and pasta cooking quality for some Canadian durum wheat genotypes. Can. J. Plant Sci. 81: 6 11620.

Nachit, M. M., Baum, M., Impiglia, A. and Ketata, H. 1995. Studies on some grain quality traits in durum wheat grown in Mediterranean environments. CIHEAM-IAMZ, Zaragoza, Spain. pp. 181187.

Pena, R. J. 2000. Durum wheat for pasta and bread-making: Comparison of methods used in breeding to determine gluten quality-related parameters. Durum wheat improvement in the Mediterranean region: New challenges. C. Royo et al. eds. No. 40. CIHEAM-IAMZ, Zaragoza, Spain. pp. 423 430.

Porceddu, E., Pacucci, G., Perrino, P., Gatta, C. D. and Maellaro, I. 1973. Protein content and seed characteristics in populations of Triticum durum grown at three locations. Proc. of the Symp. on Genetics and Breeding Durum Wheat, University of Bari, Bari, Italy. 1418 May. pp. 217222. Rani, K. U., Prasada-Rao, U. J. S., Leelavathi, K. and Haridas-Rao, P. 2001. Distribution of enzymes in wheat ﬂour mill streams. J. Cereal Sci. 34: 233242.

Rharrabti, Y., Royo, C., Villegas, D., Aparicio, N. and Garcia´ del Moral, L. F. 2003. Durum wheat quality in Mediterranean environments I. Quality expression under different zones, latitudes and water regimes across Spain. Field Crops Res. 80: 123131.

Sakin, M. A., Yildirim, A. and Gokmen, S. 2004. Determining the yield, some yield and quality components of some durum wheat cultivars and lines in Tokat-Kazova conditions. J. Agric. Sci. 10: 481489 [in Turkish].

Sakin, M. A., Yildirim, A. and Gokmen, S. 2005. Determining some yield and quality characteristics of mutants induced from a durum wheat (Triticum durum Desf.) cultivar. Turk. J. Agric. For. 29: 6 167.

Sehirali, S. and Ozgen, M. 1987. Plant genetic resources. Ankara University, Agricultural Faculty, Ankara, Turkey. Sissons, M. J. 2004. Pasta. Pages 410418 in C. Wrigley et al., eds. Encylopedia of grain science. Elsevier Ltd., Amsterdam, the Netherlands.

Sozen, E. and Yagdi, K. 2005. A research to determine agronomic traits of some advanced durum wheat lines. Uludag University J. Agric. Fac. 19 (2): 5157 [in Turkish].

TMO. 2004, 2006, 2007. TMO-History of the Turkish Grain Board [Online] Available: www.tmo.gov.tr.

Troccoli, A., Borrelli, G. M., De Vita, P., Fares, C. and Di Fonzo, N. 2000. Durum wheat quality: A multidisciplinary concept. J. Cereal Sci. 32: 99113.

TUIK. 2009. [Online] Available: www.tuik.gov.tr.

Veraverbeke, W. S. and Delcour, J. A. 2002. Wheat protein composition and properties of wheat glutenin in relation to breadmaking functionality. Crit. Rev. Food Sci. Nutr. 42: 179208.

Yildirim, A., Sayaslan, A., Kandemir, N., Eserkaya, T., Koyuncu, M. and Sonmezoglu, O. A. 2008. Screening of Turkish durum wheat landraces for gliadins and LMW-glutenins associated with pasta quality. International Durum Wheat Symposium. 2008 30 June02 July. Bologna, Italy. Williams, P. C., Nachit, M., Shehadeh, A., Sategh, A. and Michael, M. 1986. Comparative quality of Sebou with Gezira Sham 1. Rachis 5 (2): 55.