Person: Toktay, H.
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Toktay
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H.
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Toktay, H.
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0000-0003-0814-7237 10 results
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- Association analysis of resistance to cereal cyst nematodes (Heterodera avenae) and root lesion nematodes (Pratylenchus neglectus and P. thornei) in CIMMYT advanced spring wheat lines for semi-arid conditions(Japanese Society of Breeding, 2016) Dababat, A.A.; Gomez-Becerra, H.F.; Erginbas Orakci, G.; Dreisigacker, S.; Imren, M.; Toktay, H.; Elekcioglu, I.H.; Tesfamariam Mekete; Nicol, J.M.; Ansari, O.; Ogbonnaya, F.C.To identify loci linked to nematode resistance genes, a total of 126 of CIMMYT advanced spring wheat lines adapted to semi-arid conditions were screened for resistance to Heterodera avenae, Pratylenchus neglectus, and P. thornei, of which 107 lines were genotyped with 1,310 DArT. Association of DArT markers with nematode response was analyzed using the general linear model. Results showed that 11 markers were associated with resistance to H. avenae (pathotype Ha21), 25 markers with resistance to P. neglectus, and 9 significant markers were identified to be linked with resistance to P. thornei. In this work we confirmed that chromosome 4A (~90–105 cM) can be a source of resistance to P. thornei as has been recently reported. Other significant markers were also identified on chromosomal regions where no resistant genes have been reported for both nematodes species. These novel QTL were mapped to chromosomes 5A, 6A, and 7A for H. avenae; on chromosomes 1A, 1B, 3A, 3B, 6B, 7AS, and 7D for P. neglectus; and on chromosomes 1D, 2A, and 5B for P. thornei and represent potentially new loci linked to resistance that may be useful for selecting parents and deploying resistance into elite germplasm adapted to regions where nematodes are causing problem.
Publication - Resistance of winter wheat to Heterodera filipjevi in Turkey(The Scientific and Technology Research Council of Turkey, 2014) Dababat, A.A.; Erginbas Orakci, G.; Toktay, H.; Imren, M.; Akin, B.; Braun, H.J.; Dreisigacker, S.; Elekcioglu, I.H.; Morgounov, A.Cereal cyst nematodes (CCNs) are plant parasites that significantly limit global cereal production. The most frequently reported pathogenic species are Heterodera avenae, H. filipjevi, and H. latipons. One of the most cost-effective, environmentally friendly, and easily adopted control measures is the use of genetic host resistance, which maintains nematode populations below the economic damage threshold level. Many effective sources of resistance to CCNs have been identified in cereals; however, their effectiveness and usefulness is dependent on the interaction of the specific putative resistant accession and the CCN pathotype found in a specific region. In this study, 719 wheat lines from the Facultative and Winter Wheat Observation Nurseries, representing a broad geographical spectrum of breeding lines and varieties from Europe, Central Asia, and the International Winter Wheat Improvement Program, were screened against H. filipjevi under controlled conditions. The results indicated that 114 and 90 genotypes were ranked resistant and moderately resistant, representing 15.8% and 12.5% of the screened genotypes, respectively. The frequency of resistant genotypes observed in the germplasms varied significantly among the different original countries and was the highest for genotypes that originated from Bulgaria (59.3%). From those phenotyped germplasms, a set of 289 lines was genotyped to understand if resistance sources are located at the same site or originate from different locations in the genome.
Publication - Identification of genetic resistance to cereal cyst nematodes; Heterodera avenae (Wollenweber, 1924), Heterodera filipjevi (Madzhidov, 1981) Stelter and Heterodera latipons (Franklin, 1969) in some international bread wheat germplasms(Entomological Society Turkey, Ege University, 2013) Imren, M.; Toktay, H.; Bozbuga, R.; Erginbas Orakci, G.; Dababat, A.A.; Elekcioglu, I.H.The cereal cyst nematodes, Heterodera avenae group, are known as parasites of cereals worldwide. In Turkey, the cereal cyst nematodes, Heterodera filipjevi, H. avenae and H. latipons, are the three known species infested wheat fields and cause high yield losses. The using of resistance varieties is one of the most effective methods for controlling cereal cyst nematodes. Recently, resistance genes (Cre genes) which are obtained from wild wheat genotypes have been transferred into bread wheat varieties to control the cereal cyst nematodes species. In this study, the efficiency of some sources of resistance (CreR, Cre1, Cre2, Cre3, Cre7 and Cre8) in wheat against some Turkish H. avenae, H. filipjevi and H. latipons populations was investigated in-vitro conditions. According to results, the effect of resistance genes showed variation depending on different Cereal cyst nematode populations; H.avenae, H. filipjevi and H. latipons. Although Cre1 gene was only found as completely resistant to all (three) nematode species, Cre3 and Cre7 were found resistant to H. avenae and H. latipons. Cre R was also determined as resistant to H. filipjevi and H. latipons populations but Cre8 was only found resistant against to H. filipjevi population. No resistance was found in Cre 2 gene against to all nematode populations. Additionally, 2 resistance gene-free variety and lines were found resistant to H. avenae; 3 wheat lines to H. filipjevi and 11 wheat genotypes were found moderately resistant to H. latipons.
Publication - Determination of resistance against to Cereal cyst nematode, Heterodera avenae (Wollenweber, 1924) in some wheat germplasm(Entomological Society Turkey, Ege University, 2013) Imren, M.; Toktay, H.; Bozbuga, R.; Dababat, A.A.; Ozkan, H.; Elekcioglu, I.H.The cereal cyst nematode, Heterodera avenae is one of the most important pests of wheat in many countries in the world with different climatic types. Heterodera. avenae is commonly distributed in the Eastern Mediterranean region of Turkey and all populations investigated belong to the Ha1 group, Ha21 pathotype. This study was aimed to found resistance sources from the national wheat varieties, wheat wild genotypes and international wheat genotypes against H. avenae Karlık?Adana population (Ha21 pathotype). Results showed that four national wheat varieties, seventeen wheat wild genotypes and twenty three international wheat genotypes were found to be moderately resistant against to Eastern Mediterranean Region of Turkey H. avenae population. Among these genotypes, the national bread wheat variety, Adana 99 (PFAU/SERI82//BOG"S"), some wild genotypes and international genotypes can be used in national wheat breeding programmes. However, Cre1 was not showed completely resistant against H. avenae. Additionally resistance sources in of Turkish national wheat and wild genotypes needs to be determined.
Publication - Pathotype characterization of the cereal cyst nematode Heterodera filipjevi (Madzhidov, 1981) Stelter in Turkey(Entomological Society Turkey, Ege University, 2013) Toktay, H.; Imren, M.; Bozbuga, R.; Erginbas Orakci, G.; Dababat, A.A.; Elekcioglu, I.H.Turkey is ranked among top ten wheat producing countries in the world. Cereal cyst nematodes are considered one of the most damaging plant parasitic nematodes on wheat worldwide. Up to date, the most effective method of controlling this group of nematodes is the use of crop rotation and resistant varieties. The successful development of disease-resistant plants is contingent on knowledge of the pathotypes of the causal agent. In this study, three populations of Heterodera filipjevi (Madzhidov, 1981) Stelter were collected from different locations (Afsin, Elbistan and Yozgat) in Turkey in order to identify their pathotype using ?The International Test Assortment of Cereal Cultivars?. The results showed that two populations gave a similar reaction to the resistant and susceptible varieties. These populations were determined as Ha 33 pathotype which is a new report for Turkey.
Publication - Screening for resistance to Heterodera filipjevi (Madzhidov) Stelter (Tylenchida: Heteroderidae) and Pratylenchus thornei (Sher & Allen) (Tylenchida: Pratylenchidae) sister lines of spring wheat(Entomological Society Turkey, Ege University, 2012) Toktay, H.; Yavuzaslanoglu, E.; Imren, M.; Nicol, J.M.; Elekcioglu, I.H.; Dababat, A.A.Breeding for resistance to the cereal cyst nematodes (CCN) Heterodera filipjevi (Madzhidov,) Stelter, and H. avenae (Wollenweber) and to the root lesion nematode (RLN) Pratylenchus thornei (Sher & Allen) is presently being undertaken by breeding programs at research institutions in Turkey. This study was carried out to screen for nematode resistance in an advanced spring bread wheat breeding population, 42 lines (F9) developed at CIMMYT in Mexico, by crossing resistant parent the Middle- Eastern landrace AUS4930 7.2 and susceptible parent, the widely adapted, high yielding CIMMYT line, Pastor. The results demonstrate that 31 lines are resistant to P. thornei and 5 lines are resistant to H. filipjevi. Only 4 of these lines (2, 7, 23 and 41) are resistant to both nematodes. Lines 2, 7 and 41 also contain the known resistance gene, Cre1. Although some lines carry the Cre1 gene, they are susceptible to either both or one of these nematodes. There is no association among H. filipjevi, P. thornei and Cre1 resistance due to differences in the resistance region in the plant genome.
Publication - Improved methodology for resistance screening in spring wheat against the root lesion nematode, Pratylenchus thornei (Sher et Allen) (Tylenchida: Pratylenchidae)(Entomological Society Turkey, Ege University, 2012) Toktay, H.; Imren, M.; Nicol, J.M.; Dababat, A.A.; Elekcioglu, I.H.The root lesion nematode, Pratylenchus thornei (Sher et Allen) is a polyphagous and economically important nematode in wheat production systems, particularly in rainfed environments. Chemical management of this nematode is not economically or environmentally sound, leaving cultural practices like crop rotation as the most widely accepted option. Long-term control is best achieved in established wheat monoculture systems through genetic improvement, which provides both economic and environmental benefits to the growers. Intensive screening under controlled conditions can facilitate and accelerate the identification of resistance and its subsequent deployment in commercial wheat cultivars. In this study, a number of variables were assessed to optimize P. thornei screening, including initial nematode density, soil type, container size, reference cultivars, harvest time and watering regime with perlite. Growth room experiments showed clear separation between the resistant and susceptible cultivars, using sandy growth edium (70:29:1 sand, field soil and organic matter), small container (15 mm diameter x 100 mm in long), inoculation density with 400 individuals per plant, 9 week growing period and bottom perlite irrigation system.
Publication - Pathotype determination of the cereal cyst nematode, Heterodera avenae (Wollenweber, 1924) in the Eastern Mediterranean Region in Turkey(Türkiye Entomoloji Derneği, 2012) Imren, M.; Toktay, H.; Bozbuga, R.; Dababat, A.A.; Elekcioglu, I.H.Karlik (Adana-Saricam), Imece (Hatay-Kirikhan) and Beþaslan (Hatay-Reyhanli) populations were used to determine the pathotype of the cereal cyst nematode, Heterodera avenae, in the Eastern Mediterranean Region of Turkey. Pathotype of H. avenae were investigated by using ?The International Test Assortment of Cereal Cultivars?. The test was conducted on twelve barley, six oat, six wheat and four control lines (milan, seri, silverstar and croc). Test materials were grouped by three nematode populations virulence on resistance (Rha?E?, Rha1, Rha2, Rha3, Cre1) and nonresistance genes variety and lines. According to results, Rha1 and Rha3 genes gave a resistance response but Rha2 and Cre1 did not. As a result, all populations demonstrated similar reactions and the three nematode populations were consistent with reactions for the Ha21 pathotype of the Ha1 group. This result is the first report on determining of the H. avenae pathotype in Turkey.
Publication - Molecular characterization of cereal cyst nematodes from South Anatolian region in Turkey using ITS-rDNA sequences(Türkiye Entomoloji Derneği, 2012) Imren, M.; Waeyenberge, L.; Viaene, N.; Toktay, H.; Dababat, A.A.; Elekcioglu, I.H.The Heterodera avenae group includes 12 species feeding on roots of cereals. Three species, Heterodera avenae Wollenweber, 1924, Heterodera filipjevi (Madzhidov, 1981) Stelter, 1984 and Heterodera latipons Franklin, 1969 are among the most economically important cyst nematode pests towards cereals cultivated in different parts of Turkey. In this study, forty seven cereal cyst nematode isolates collected from cereal growing areas of South Anatolian Region of Turkey (Hatay, Kahramanmaraþ, Gaziantep, Kilis, Mardin and Adýyaman), were identified using sequence analysis of the Internal Transcribed Spacer region of the ribosomal DNA (ITS-rDNA). Based on phylogenetic analysis using ITS-rDNA sequences, H. avenae, H. filipjevi, H. latipons and Heterodera ciceri Vovlas, Greco & Di Vito, 1985 were identified. According to our results, 76,5 % of the isolates could be characterized as H. latipons, 13 % H. filipjevi, 8,5 % H. avenae and 2 % H. ciceri.
Publication - Heterodera avenae yumurtalarinin inkubasyonu uzerine sicakligin etkisi ile en uygun deneme yontem ve materyallerinin arastirilmasi(Türkiye Entomoloji Derneği, 2012) Imren, M.; Toktay, H.; Ozarslandan, A.; Dababat, A.A.; Elekcioglu, I.H.In this study, the effect of temperatures on the incubation duration of the cereal cyst nematode cysts, Heterodera avenae (Wollenweber, 1924) and determining of the optimum methods and materials was investigated under in-vitro conditions. The effect of tempratures on incubation duration of Heterodera avenae cysts was studied on two different incubation stages. First incubation exposured to all cysts was set up 66 days at 4ºC after each samples transfered different temperatures (5, 10, 15, 20 and 25ºC). The cumulative hatching percent was significantly effected by different temperatures at the end of 252 days. Hatching was greater at lower temperatures (5, 10 15 ºC) compared to at higher temperatures of (20, 25ºC) ranging between 46.7, 82.3 and 45.9 % vs and 30.7 and 19.0%, respectively. Although the highest cumulative hatching of 82.3% was obtained at a constant 10ºC at 252 days, the lowest cumulative hatching of 19.0% was obtained to 25ºC at 252 days. The most suitable soil type for the in-vitro conditions was found the sandy soil (70 % sand: 29% field soil: 1% organic matter), best inoculation rate was 2,5 second stage juveniles per gram soil and inoculation time at planting day.
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