Yazar "Dababat, Abdelfattah A." seçeneğine göre listele

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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 SOC BREEDING, 2016) Dababat, Abdelfattah A.; Ferney, Gomez-Becerra Hugo; Erginbas-Orakci, Gul; Dreisigacker, Susanne; Imren, Mustafa; Toktay, Halil; Ogbonnaya, Francis
    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 (similar to 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.
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    Morphological and Biochemical Changes in the Mediterranean Cereal Cyst Nematode (Heterodera latipons) during Diapause
    (Mdpi, 2024) Abumuslem, Motasem; Toktay, Halil; Sadder, Monther T.; Dababat, Abdelfattah A.; Salem, Nida' M.; AL-Banna, Luma
    The cereal cyst nematode (Heterodera latipons) is becoming an economically important species in global cereal production as it is being identified in many new cereal cultivated areas and causes significant losses. Consequently, understanding its biology becomes crucial for researchers in identifying its vulnerabilities and implementing effective control measures. In the current study, different morphological and biochemical changes of H. latipons cysts containing eggs with infective juveniles from a barley field in Jordan were studied during the summer of 2021, at two sample dates. The first, at the harvest of the cereal crop (June 2021), when the infective second-stage juveniles (J2s) were initiating diapause, and the second, before planting the sequent cereal crop (late October 2021), when the J2s were ending diapause. The studied population was characterized morphologically and molecularly, showing 98.4% molecular similarity to both JOD from Jordan and Syrian 300 isolates of H. latipons. The obtained results and observations revealed that there were dramatic changes in all the investigated features of the cysts and eggs they contained. Morphological changes such as cyst color, sub-crystalline layer, and thickness of the rigid eggshell wall were observed. A slight change in the emergence time of J2s from cysts was observed without any difference in the number of emerged J2s. The results of biochemical changes showed that the total contents of carbohydrates, glycogen, trehalose, glycerol, and protein were higher in cysts collected in October when compared to those cysts collected in June. The SDS-PAGE pattern indicated the presence of a protein with the size of ca. 100 kDa in both sampling dates, whereas another protein (ca. 20 kDa) was present only in the cysts of October. Furthermore, the expression of trehalase (tre) gene was detected only in H. latipons collected in October. The outcomes of this study provide new helpful information that elucidates diapause in H. latipons and may be used for the implementation of new management strategies of cyst nematodes.
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    Occurrence and identification of cereal cyst nematode, Heterodera filipjevi (Nemata: Heteroderidae), in Bolu province of Turkey
    (Organization of Nematologists of Tropical America, 2016) Imren, Mustafa; Toktay, Halil; Kutuk, Halil; Dababat, Abdelfattah A.
    Cereal cyst nematodes, Heterodera filipjevi, parasitize the roots of wheat and cause significant yield losses around the world. Cereal cyst nematodes are one of the most important and endemic problems in wheat-growing areas especially where rainfall is limited and monoculture crop production practices exist. In Turkey, cereal cyst nematodes are considered among the most damaging pests in wheat. Identifying cyst nematode species and determining their prevalence and distribution in Turkey are important for predicting potential spread in the future. This survey aimed to identify cyst nematode species and to assess their prevalence in cereal growing areas of Bolu province in Turkey. Cereal cyst nematode cysts were found in 83% of the surveyed fields. Prevalence of cysts was greater in cereal-growing areas in the provincial center and in the Gerede district. Morphological features of second-stage juveniles and cysts were examined, and DNA was extracted from second-stage juveniles and the species-specific Sequence Characterized Amplified Region (SCAR) primers were used for molecular identification. Based on both morphological and molecular methods, all samples were identified as H. filipjevi. This study was the first comprehensive investigation of H. filipjevi prevalence in cereal fields in Bolu. This information is of value to alert personnel of wheat breeding programs to develop local resistant varieties to target H. filipjevi.
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    OCCURRENCE AND IDENTIFICATION OF CEREAL CYST NEMATODE, HETERODERA FILIPJEVI (NEMATA: HETERODERIDAE), IN BOLU PROVINCE OF TURKEY
    (Organization Trop Amer Nematologists, 2016) Imren, Mustafa; Toktay, Halil; Kutuk, Halil; Dababat, Abdelfattah A.
    Cereal cyst nematodes, Heterodera filipjevi, parasitize the roots of wheat and cause significant yield losses around the world. Cereal cyst nematodes are one of the most important and endemic problems in wheat-growing areas especially where rainfall is limited and monoculture crop production practices exist. In Turkey, cereal cyst nematodes are considered among the most damaging pests in wheat. Identifying cyst nematode species and determining their prevalence and distribution in Turkey are important for predicting potential spread in the future. This survey aimed to identify cyst nematode species and to assess their prevalence in cereal growing areas of Bolu province in Turkey. Cereal cyst nematode cysts were found in 83% of the surveyed fields. Prevalence of cysts was greater in cereal-growing areas in the provincial center and in the Gerede district. Morphological features of second-stage juveniles and cysts were examined, and DNA was extracted from second- stage juveniles and the species-specific Sequence Characterized Amplified Region ( SCAR) primers were used for molecular identification. Based on both morphological and molecular methods, all samples were identified as H. filipjevi. This study was the first comprehensive investigation of H. filipjevi prevalence in cereal fields in Bolu. This information is of value to alert personnel of wheat breeding programs to develop local resistant varieties to target H. filipjevi.
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    Phytophagous nematodes in cereal fields in Nigde Province, Turkey
    (Entomological Soc Turkey, Ege Univ, 2020) Toktay, Halil; Imren, Mustafa; Akyol, Badel G.; Evlice, Emre; Riley, Ian T.; Dababat, Abdelfattah A.
    This study evaluated the occurrence and incidence of phytophagous nematodes and identified the cereal cyst nematode species by morphological and molecular tools in the main cereal-growing areas in Nigde in 2018-2019. Phytophagous nematodes within twelve genera were detected in 95% of soil samples. The most common phytophagous nematodes in cereal soil were in the genera Heterodera, Ditylenchus, Merlinius, Pratylenchus, Aphelenchus, Aphelenchoides, Tylenchus, Helicotylenchus, Trophurus, Pratylenchoides, Filenchus and Xiphinema (in decreasing order of incidence). In particular, 75% of the soil samples from surveyed fields were infested with the cereal cyst nematodes (Heterodera spp.). Morphological characteristics of cysts and second-stage juveniles were calculated within the expected ranges for Heterodera filipjevi (Madzhidov, 1981) Stelter, 1984, however, two populations from Camardi was determined as Heterodera latipons Franklin, 1969 (Tylenchida: Heteroderidae). Intraspecific variation was not observed within the populations of H. filipjevi which could be in the same genotypic group. In addition to the high incidence of these Heterodera spp., intensive cereal cropping systems with/without non-cereal rotations in wheat production areas of Nigde also resulted in high incidence of root lesion nematode, Pratylenchus species.
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    Resistance of winter wheat to Heterodera filipjevi in Turkey
    (TUBITAK SCIENTIFIC & TECHNICAL RESEARCH COUNCIL TURKEY, 2014) Dababat, Abdelfattah A.; Erginbas-Orakci, Gul; Toktay, Halil; Imren, Mustafa; Akin, Beyhan; Braun, Hans-Joachim; Morgounov, Alexei
    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.
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    The importance and management strategies of cereal cyst nematodes, Heterodera spp., in Turkey
    (SPRINGER, 2015) Dababat, Abdelfattah A.; Imren, Mustafa; Erginbas-Orakci, Gul; Ashrafi, Samad; Yavuzaslanoglu, Elif; Toktay, Halil; Mekete, Tesfamariam
    Cereal cyst nematodes (CCNs) can cause significant economic yield losses alone or in combination with other biotic and abiotic factors. The damage caused by these nematodes can be enormous when they occur in a disease complex, particularly in areas subject to water stress. Of the 12 valid CCN species, Heterodera avenae, H. filipjevi, and H. latipons are considered the most economically important in different parts of the world. This paper reviews current approaches to managing CCNs via genetic resistance, biological agents, cultural practices, and chemical strategies. Recent research within the soil borne pathogen program of the International Maize and Wheat Improvement Center has focused on germplasm screening, the potential of this germplasm as sources of resistance, and how to incorporate new sources of resistance into breeding programs. Breeding for resistance is particularly complicated and difficult when different species and pathotypes coexist in nature. A lack of expertise and recognition of CCNs as a factor limiting wheat production potential, combined with inappropriate breeding strategies and slow screening processes limit genetic gains for resistance to CCNs.