Lehrstuhl für Pflanzenzüchtung

Root Lesion Nematode Resistance in Cereals

Genetic variation for Resistance

 

 

 

 

 

 

 

 

Background

Plant parasitic nematodes from the genus Pratylenchus are major pests in agriculture and attack a wide spectrum of crops including barley, wheat, rape seed, maize, potato, alfalfa, and carrots. The penetration of the nematodes in the roots also leads to secondary infections by fungi or other pathogens that, together with reduction in nutrients- and water-uptake, drastically reduce yield. In the past decade, severe damage in German cereal production has been reported and this pest is regarded by farming experts as a major threat for cereal production. Narrow crop rotation, early-sowing dates, and mild winters which are expected due to climate change increase the damage by this pest.

In a previous work, we have identified several QTL for root lesion nematode resistance in barley (Galal et al. 2014; Sharma et al. 2011, Keil et al. 2009). In this project, we will identify all genes annotated for these intervals and use this information for sequence homology search to different sequence resources of the wheat genome. Based on this analysis, we will identify wheat orthologs of the respective barley candidate genes and test allelic diversity and gene expression in a panel of resistant and susceptible wheat cultivars that will be identified during this project.

Objectives

We are aiming at the identification of QTL for root lesion nematode resistance in wheat. For this, we will determine the abundance of RLN in production fields in (northern) Germany and to select wheat genotypes with low infection by RLN adapted to central European climate conditions. At the end, we want to identify the genetic and physiological reasons for RLN resistance in cereals. To overcome the bottlenecks of the phenotyping tests, we are developing an RTqPCR based method to quantify nematode in infected roots.  

Results

Up to now, 122 soil samples from different geographical regions in Germany were investigated and the presence of RLN belonging to the genus Pratylenchus was verified for 99% of the samples. To identify RLN QTL(s) present in European wheat material, 182 out of 300 lines were tested for resistance against P. neglectus in a glasshouse experiment by inoculating 6 plants of each line with 1,000 nematodes (Pi) and counting the nematodes after 7 weeks (Pf). We observed Pf/Pi values varying from 0.28 for “WW5673” up to 7.18 for “Texel”, showing a big variation among the investigated lines. For an association analysis, genotypic data from 15k, 20k, or 90k Chip-arrays are available. Field trials in highly infested soils using 20 selected wheat lines varying according to their resistance level to RLN is presently running and will be repeated in 2018/2019. The effect of RLN resistance on yield and other agronomically important parameters will be estimated. In a final step, we will compare candidate genes from resistance QTL from barley and wheat exploiting the high conservation of gene order and sequences between both species.

Project team

Dr. Gina Capistrano-Goßmann
Brigitte Neidhardt-Olf
Bettina Rohardt
Prof. Dr. Christian Jung
B.Sc. Calista Randazzo

Scientific Partners

Prof. Dr. Johannes Hallmann, Institute for Epidemiology and Pathogen Diagnostics, JKI Münster
http://www.jki.bund.de/no_cache/de/startseite/institute/epidemiologie-pathogendiagnostik/personal/dr-hallmann-johannes.html

Dr. Nils Stein, IPK Gatersleben
http://www.ipk-gatersleben.de/genbank/genomik-genetischer-ressourcen/

Prof. Dr. Frank Ordon, Institute for Resistance Research and Stress Tolerance, JKI Quedlinburg
http://www.jki.bund.de/no_cache/de/startseite/institute/resistenzforschung-stresstoleranz/personal/ordon-frank.html

Prof. Dr. Birgit Classen, Institute of Pharmaceutical Biology, Kiel University
https://www.mnf.uni-kiel.de/de/gleichstellung/gb-mnf/team-1/classen

Other Partners

Dr. Martin Kirchhoff, Dr. Eberhard Laubach, Nordsaat Saatzucht GmbH
http://www.nordsaat.de/

Karin Riemer, Bundessortenamt
http://www.bundessortenamt.de/internet30/index.php?id=3

Publications

Galal A., Sharma S., Abou-Elwafa S. F., Sharma S., Kopisch-Obuch, F., Laubach, E., Perovic D., Ordon F. and Jung C. (2014). Comparative QTL analysis of root lesion nematode resistance in barley. Theor. Appl Genet 127(6): 1399-1407

A. Galal (2014) Mapping Root-Lesion Nematode Resistance QTL in Barley (Hordeum vulgare L.). Doktorarbeit Lehrstuhl Pflanzenzüchtung, Universität Kiel.

Sharma S., S. Sharma, T. Keil, E. Laubach and C. Jung (2011). Screening of barley germplasm for resistance to root lesion nematodes. Plant Genetic Resources 9(02): 236-239.

Sharma S., S. Sharma, F. J. Kopisch-Obuch, T. Keil, E. Laubach, N. Stein, A. Graner and C. Jung (2011). QTL analysis of root-lesion nematode resistance in barley: 1. Pratylenchus neglectus. Theor Appl Genet 122:1321–1330.

Keil T., E. Laubach, S. Sharma and C. Jung (2009). Screening for resistance in the primary and secondary gene pool of barley against the root-lesion nematode Pratylenchus neglectus. Plant Breeding 128; 436-442

T. Keil. Selektion von Gerstenherkünften mit Resistenz gegen freilebende Nematoden der Gattung Pratylenchus. Doktorarbeit Lehrstuhl Pflanzenzüchtung, Universität Kiel. 2008.

Posters and Oral Presentations

Capistrano-Goßmann, G., Hachtel, J., Hallmann, J., Pidon, H., Stein, N., Kirchhoff, M., Classen, B., Laubach, E., Riemer, K., Soleimani, B., Perovic, D., Ordon, F., Jung, C. NEMARES: Importance of root lesion nematodes in German crop production and strategies to breed resistant varieties 6th International Cereal Nematode Symposium, Agadir, Morocco, September 11-15, 2017, oral presentation. PLANT 2030 Status Seminar 2018, Oral presentation.

Soleimani, B., Lehnert, H., Perovic, D., Capistrano-Gossmann, G., Jung, C., Ordon, F. The application of K-medoids for selecting wheat lines genotyped using various SNP platforms to be used in genome wide association studies for nematode resistance. PLANT 2030 Status Seminar 2018, Poster.

Soleimani, B., Perovic, D., Capistrano-Gossmann, G., Jung, C., Ordon, F. Selection of diverse set of wheat genotypes for conducting genome wide association studies for nematode resistance 10th Young Scientists Meeting, Siebeldingen, Germany, November 08-10, 2017, oral presentation.

Capistrano-Goßmann, G., Hachtel, V., Klemm, J., Hallmann, J., Pidon, H., Perovic, D., Kirchhoff, M., Laubach, E., Riemer, K., Classen, B., Soleimani, B., Stein, N., Ordon, F., Jung, C. NEMARES: Importance of root lesion nematodes in German crop production and strategies to breed resistant varieties 6th International Cereal Nematode Symposium, Agadir, Morocco, September 11-15, 2017, oral presentation.

Financial Support (start in 2016)

Federal ministry for research and technology (BMBF), Acromyn: NEMARES.

 

Updated: Aug - 2018        Responsible for this webpage: Dr. G. Capistrano-Goßmann