Julie Nicol

Followers

Following

Co-author

Public Views

Interests

Uploads

Papers by Julie Nicol

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

Breeding Science, 2016

To identify loci linked to nematode resistance genes, a total of 126 of CIMMYT advanced spring wh... more 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.

format_quoteIdentified 60 significant MTAs for nematode resistance, with 45 confirmed post-FDR, providing vital markers for breeding programs.format_quote

Download

Bazı ekmeklik buğday hatlarının Heterodera filipjevi (Madzhidov) Stelter (Tylenchida: Heteroderidae) ve Pratylenchus thornei (Sher & Allen) (Tylenchida: Pratylenchidae)‘ye karşı reaksiyonlarının araştırılması

Breeding for resistance to the cereal cyst nematodes (CCN) Heterodera filipjevi (Madzhidov,) Stel... more 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....

format_quoteF 9 population screening found 15 lines with the CCN resistance gene Cre1, indicating potential for nematode-resistant wheat.format_quote

Download

Tahıl kist nematodu, Heterodera filipjevi (Madzhidov, 1981) Stelter’nin patotipinin belirlenmesi ve buğday genotiplerinin, H. filipjevi populasyonlarına karşı dayanıklılıklarının araştırılması

Turkish journal of entomology, Aug 1, 2010

*Summary Determination of the pathotype group of Heterodera filipjevi (Madzhidov, 1981) populatio... more *Summary Determination of the pathotype group of Heterodera filipjevi (Madzhidov, 1981) population and resistance of H. populations against wheat genotypes The international pathotype differential lines were used to determine the pathotype group of Heterodera filipjevi (Madzhidov, 1981) Stelter population collected from Yozgat province, Turkey. The reaction of H. filipjevi Yozgat population on the differential lines indicated they were different than the other 5 known H. filipjevi pathotypes. Futherwork was conducted with these H. filipjevi populations to assess the usabilitiy of known published Cereal Cyst Nematode (CCN) resistance genes against a closely related species and pathotypes of Heterodera avenae Wollenweber, 1924. Several of these wheat lines known to possess resistance against H. avenae pathotypes and also the Haymana H. filipjevi populations did not exhibit resistance against H. filipjevi Yozgat populations.

Determination of the pathotype group of Heterodera filipjevi (Madzhidov, 1981) population and resistance of H. filipjevi populations against wheat genotypes

Turkish journal of entomology, 2010

Determination of the pathotype group of Heterodera filipjevi (Madzhidov, 1981) population and res... more Determination of the pathotype group of Heterodera filipjevi (Madzhidov, 1981) population and resistance of H. populations against wheat genotypes The international pathotype differential lines were used to determine the pathotype group of Heterodera filipjevi (Madzhidov, 1981) Stelter population collected from Yozgat province, Turkey. The reaction of H. filipjevi Yozgat population on the differential lines indicated they were different than the other 5 known H. filipjevi pathotypes. Futherwork was conducted with these H. filipjevi populations to assess the usabilitiy of known published Cereal Cyst Nematode (CCN) resistance genes against a closely related species and pathotypes of Heterodera avenae Wollenweber, 1924. Several of these wheat lines known to possess resistance against H. avenae pathotypes and also the Haymana H. filipjevi populations did not exhibit resistance against H. filipjevi Yozgat populations.

Download

Screening for resistance to Heterodera filipjevi and Pratylenchus thornei in sister lines of spring wheat

Turkish journal of entomology, 2012

Breeding for resistance to the cereal cyst nematodes (CCN) Heterodera filipjevi (Madzhidov,) Stel... more 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 (F 9) 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.

Download

The distribution, pathogenicity and population dynamics of Pratylenchus thornei on wheat in South Australia / Julie Margaret Nicol

Declaration Acknowledgements Abbreviations Chapter I 2.3.1 Biology 2.3.2 Histopathology 2.3.3 Lif... more Declaration Acknowledgements Abbreviations Chapter I 2.3.1 Biology 2.3.2 Histopathology 2.3.3 Life Cycle Symptoms Associations with Other Pathogens Environmental Infl uences 2.6.1 Climate 2.6.2 Soil 2.6.3 Nutrition Survival Economic Importance Population Dynamics and Control Measures 2.9.I Chemical Control 2.9.2 Cultural Practices 2.9.3 Biological Control 2.9.4 Resistance and Tolerance Chapter 3 General Laboratory Techniques 3.1 Nematorle Inocula 3.2 NematodeExtraction 3.2.1 Soil 3.2.2 Root 3.3 Nematode Counting 3.4 Staining Nematodes and./or Fungi 3.4.I Nematodes Only 3.4.2 Nematodes plus Fungi 42 42 3.6.r 3.6.2 3.6.3 3.7 C,lassification of Soils used in Laboratory Experiments lll Chapter 4 støtewid.e sary.ey for P. thornei and p. neglectus ín the cereal Regions of South Australia Introduction Materials and Methods Results Discussion 4.1 4.2 4.3 4.4

format_quoteP. thornei reduces grain yield through cortical root degradation, impacting water and nutrient absorption.format_quote

Download

Determination of fusarium crown rot resistance in wheat to Fusarium culmorum and Fusarium pseudogramineaum using real time PCR

Crop Protection, 2020

Abstract Wheat varieties from Turkey, Australia and the Pacific Northwest of the US were screened... more Abstract Wheat varieties from Turkey, Australia and the Pacific Northwest of the US were screened for resistance to Fusarium crown rot (Fusarium pseudograminearum and Fusarium culmorum) in inoculated growth chamber studies. Fungal DNA was also quantified from the lower stems (crowns) of seedlings using quantitative PCR and crown rot scores were correlated with DNA results. There were significant differences among the varieties for crown rot severity index (p = 0.0265), crown rot score (p = 0.0003), disease index on leaf sheaths (leaf sheath score) (p = 0.0013), lesion length (p = 0.0200), and plant height (p

Distribution of the Cereal Cyst Nematodes (Heterodera spp.) in Wheat and Barley Fields in North-Eastern Regions of Syria

Journal of Plant Diseases and Protection, 2015

Cereal cyst nematodes (CCN) are important plant-parasitic nematodes of wheat and barley, and exis... more Cereal cyst nematodes (CCN) are important plant-parasitic nematodes of wheat and barley, and exist in most of the cereal growing regions of the world. As there is limited information on the nature and distribution of CCN species in Syria, a survey was conducted in northeastern Syria to assess the distribution of CCN in the main wheat and barley growing areas. In the summer of 2009, a total of 167 composite soil samples were collected from 167 wheat and barley fields. Cysts were extracted from soil using the Fenwick can technique, then quantified and identified up to the species level by using both morphological and molecular methods. The study revealed that 62% of the fields were infested with the three Heterodera species: H. avenae, H. filipjevi and H. latipons. However, the most prevalent species was H. latipons, which was present in 76% of the infested samples, while it occurred alone in 67% of those samples. Heterodera avenae was detected singly in 20% of the samples, while 11% consisted of mixed populations with other species. Heterodera filipjevi was never detected alone; it was found mixed with H. avenae and/or H. latipons in 9% of the samples. The high number of extracted cysts (up to 116 cysts × 200 g-1 of soil) is most likely related to the monoculture practiced in that region and the fact that growers are unaware of the existence of resistant varieties.

format_quote116 cysts/200 g of soil linked to monoculture practices and lack of resistant varieties in the region.format_quote

Download

Global Knowledge And Its Application For The Integrated Control And Management Of Nematodes On Wheat

Integrated Management and Biocontrol of Vegetable and Grain Crops Nematodes, 2008

Page 1. 251 A. Ciancio &amp;amp;amp;amp;amp;amp; KG Mukerji (eds.), Integrated Management and... more

Assessment of inoculation methods to identify resistance to Fusarium crown rot in wheat

Journal of Plant Diseases and Protection, 2016

Crown rot, caused by Fusarium culmorum and Fusarium pseudograminearum, is one of the most pervasi... more Crown rot, caused by Fusarium culmorum and Fusarium pseudograminearum, is one of the most pervasive diseases of wheat throughout the world. Fusarium culmorum is the most prevalent causal agent in Turkey while F. pseudograminearum is the most predominant in the USA. Consistent and reliable screening methods are required to accelerate the identification and development of wheat cultivars for resistance to Fusarium crown rot in breeding programs. A multifactor experiment with seven replicates was established investigating three different inoculation techniques (seedling dip, stem base droplet and colonized grain) using two pathogenic isolates of F. culmorum in Turkey and Fusarium pseudograminearum in the USA, respectively, against known moderately resistant and susceptible wheat cultivars under controlled greenhouse conditions. Plants were harvested and evaluated for crown rot severity using a 0-10 rating scale. Results indicated that disease severity was greater in seedling dip, compared to colonized grain, and stem base inoculation (in decreasing order of severity), respectively. However, the colonized grain method produced an adequate level of severity and consistent cultivar ranking in both experiments. Results showed significant cultivar 9 inoculation method interactions, and the two species of Fusarium were considered to be virulent.

format_quoteANOVA revealed highly significant differences for inoculation methods (P < 0.0001) affecting Fusarium culmorum severity, showing methodological impact on infection rates.format_quote

Download

Cimmyt’s Approach to Identify and Use Resistance to Nematodes and Soil-Borne Fungi, in Developing Superior Wheat Germplasm

Developments in Plant Breeding, 2001

... per plant SED= 2 17 ES0 (H avenae) AUSTRALIA, mean number cysts per plant (tested tn France) ... more

Development of qPCR assays for quantitative detection of Heterodera avenae and H. latipons

European Journal of Plant Pathology, 2015

ABSTRACT Twelve Heterodera species are considered of major economic significance in cereals of wh... more ABSTRACT Twelve Heterodera species are considered of major economic significance in cereals of which Heterodera avenae, H. latipons and H. filipjevi are the most important. Precise identification and quantification of these nematodes are necessary to develop effective integrated pest control. This study reports on the use of the mitochondrial cytochrome oxidase subunit 1 (COI) gene to develop qPCR assays that could be used for the identification and quantiﬁcation of H. avenae and H. latipons. Two qPCR primer sets, each comprising two primers and a probe, were designed for each of both species. After optimization, the qPCR assays using a single second-stage juvenile (J2) were able to identify and quantify H. avenae and H. latipons. Their speciﬁcity was conﬁrmed by the lack of ampliﬁcation of J2 of 14 other Heterodera species. A qPCR using DNA extracted from 120 J2 + eggs of H. avenae and H. latipons resulted in steady Ct-values (Ct = 22.33 ± 0.1 and Ct= 21.83 ± 0.12, respectively). Dilution series of DNA extracted from 120 J2 + eggs of the two species were made. The assays for both species resulted in a standard curve showing a highly significant linearity between the Ct-values and the dilution rates (R² = 0.99; slope = -3.03 and R² = 0.99; slope = -3.28 for H. avenae and H. latipons, respectively). The two qPCR assays provide a sensitive and valid tool for rapid detection and quantiﬁcation of the two species whether they occur alone or in mixtures with other species.