Source: NORTH DAKOTA STATE UNIV submitted to
CROSS-TALK BETWEEN WHEATâ¿¿S IMMUNE RESPONSES TO INSECTS AND PATHOGENS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
1008803
Grant No.
(N/A)
Project No.
ND02389
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Nov 25, 2015
Project End Date
Sep 30, 2020
Grant Year
(N/A)
Project Director
Harris, MA, OL.
Recipient Organization
NORTH DAKOTA STATE UNIV
(N/A)
FARGO,ND 58105
Performing Department
School of Natural Resource Sciences
Non Technical Summary
Wheat is one of the world's most important crops, providing a significant portion of the foodcalories that humans directly consume in both developed and developing countries. It also is one of the world's most versatile crop plants, growing in a wide range of climatic regions and producing more types of food than any other grain crop.Threats to wheat production come from an array of phylogenetically diverse organisms, including plant pathogens, nematodes, mites, and insects. Relative to other major crops like corn, Zea mays L., and soybeans Glycine max (L.) Merr., wheat is unusual in that biotic stress is managed to a larger extent by deploying cultivars that are protected by Resistance genes. Resistance gene-protected wheat cultivars are expected to play an even bigger role in the future, when plant breeders reap the benefits of decades-long progress in molecular biology and genomics.One thing that is lackingis an understanding of how crop species integrate the diverse defense responses they require to survive attack by their many parasites. Every crop species is attacked by a large set of phylogenetically diverse parasites, which differ in how and when they attack, what they take from the plant, and their evolutionary potential for adaptation. As we learn more and more about the sensory and signaling abilities of plants, it only gets harder to understand how plants make sense of all of this information about their parasites and decide what to do. One plant for which we are beginning to understand integrated responses to biotic stress is the model plant Arabidopsis thaliana (L.) Heynh., which has, by far, the best molecular research tools.If we are to feed the 9.6 billion people expected to inhabit the Earth in 2050, research efforts similar to that now occurring for Arabidopsis must begin for major crop species, especially those crops that are not being protected from biotic stress by traits that are genetically modified. In a recently published review in the Journal of Experimental Botany (Harris et al. 2015), we made the argument that wheat is a strong candidate for such a research initiative. Briefly, the argument was that wheat 1) is critical for feeding the world's current and future populations, 2) is not currently grown as a genetically modified organism and therefore still relies on non-GM traits for protection against biotic stress, 3) has a foundation of knowledge about its immune system, including 479 Resistance (R) genes, and 4) R gene-mediated defense protects against a range of phylogenetically diverse and economically important parasites, including viruses, bacteria, fungi, nematodes, insects, and mites. Our review papersignaled the launch of a research initiative to understand how wheat integrates its immune responses to biotic stress, beginning with a focus on R gene-mediated defense. Research will focus on two economically important groups of plant parasites:insects and fungal pathogens. The Hessian fly, Mayetiola destructor (Say)is a good choicebecause it shares many features with plant pathogens, in particular fungal pathogens.On the plant pathogen side, we chose fungal pathogens because of: 1) their economic importance, 2) extensive local scientific expertise, both at North Dakota State University and the Cereal Research Unit at ARS-USDA, and 3) readily available tools, including near-isogenic lines with resistance to Puccinia triticina Erikss. (1899).
Animal Health Component
0%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
21115491060100%
Knowledge Area
211 - Insects, Mites, and Other Arthropods Affecting Plants;

Subject Of Investigation
1549 - Wheat, general/other;

Field Of Science
1060 - Biology (whole systems);
Goals / Objectives
Determine if the wheat (Triticum aestivum L.) Resistance genes that provide protection against pathogens have any effect on wheat's protection against the Hessian fly (Mayetiola destructor Say).Determine if wheat Resistance genes that protect against the Hessian fly have any effect on wheat's protection against pathogens.Determine if simultaneous attack of resistant wheat genotypes by Hessian fly and pathogens alters the effectiveness of wheat's R gene-mediated resistance for Hessian fly or wheat pathogens.
Project Methods
Wheat parasites used in experiments will come from laboratory cultures, from either our lab (Hessian fly), Dr Acevedo's lab, (biotrophic pathogens including leaf rust Puccinia triticina), or Dr Friesen's lab (necrotrophic pathogens including Stagonospora nodorum). When possible, wheat genotypeswill be near-isogenic lines (NILs), with single R genes backcrossed (>6xs) into a susceptible background. The set of NILs that we will use for testing effects of individual leaf rust Resistance genes (Lr genes) are the 'Thatcher' near-isogenic lines (Kolmer 1996, Wang et al. 2013). The set of NILs for testing effects of individual Hessian fly Resistance genes (H genes) was created by Patterson et al. (1994). Genetic analysis of the latter group of NILs (Xu et al. 2011) showed that each resistant genotype is 99% similar to the susceptible genotype. Procedures for measuring survival, growth, and reproductive success of insects and plant will be similar to those we have developed over the past decade and described in our publications (Harris et al. 2001, 2006, 2010, 2012, Anderson and Harris 2006, 2008, Anderson et al. 2011, 2012, Zhang et al. 2011). Experiments will be conducted using a factorial treatment design and arandomized complete block design, with individual plants as replicates (n = 20). JMP Statistical Software (SAS Institute 1999) will be used for analyses.For Objective One, there will betwo plant types, near-isogenic wheat genotypes expressing or not expressing the R gene for pathogen resistance, and two parasite treatments, no attack by the Hessian fly (control) or attack by the Hessian fly. This creates four treatments: 1) wheat genotype without the pathogen R gene that is not attacked by larvae, 2) wheat genotype without the pathogen R gene that is attacked by larvae, 3) wheat genotype with the pathogen R gene that is not attacked by larvae and 4) wheat genotype with the pathogen R gene that is attacked by larvae.For Objective Two, we again will use a factorial treatment design with two plant types, near-isogenic wheat genotypes expressing or not expressing the Hessian fly R gene, and two parasite treatments, no attack by the pathogen (control) or attack by the pathogen. This creates four treatments: 1) wheat genotype without the Hessian fly R gene that is not attacked by the pathogen, 2) wheat genotype without the Hessian fly R gene that is attacked by the pathogen, 3) wheat genotype with the Hessian fly R gene that is not attacked by the pathogen, and 4) wheat genotype with the Hessian fly R gene that is attacked by the pathogen. For Objective Three there will beeight treatments: 1) wheat with insect resistance that is not attacked, 2) wheat with pathogen resistance that is not attacked, 3) wheat with insect resistance attacked by insects, 4) wheat with pathogen resistance attacked by insects, 5) wheat with insect resistance attacked by the pathogen, 6) wheat with pathogen resistance attacked by the pathogen, 7) wheat with insect resistance attacked by insects and pathogens, and 8) wheat with pathogen resistance attacked by insects and pathogens.

Progress 11/25/15 to 09/30/20

Outputs
Target Audience: Nothing Reported Changes/Problems:Restrictions due to the pandemic limited research on this project. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Work in 2020 was limited due to restrictions because of the coronavirus pandemic. We had four objectives: 1) Evaluate Aegilops tauschii collections for resistance to Hessian fly, 2) identify the H genes in resistant accessions, 3) map-based cloning of resistance genes, and 4) marker-assisted selection for resistance genes for Hessian fly. For objective One, 673 accessions were evaluated from three different gene banks (WGRC, NSGC and AAFC). Resistance to Hessian fly was identified in 92/673 accessions. For Objective two, synthetic hexaploid wheat lines were also screened, with about 25 lines showing resistance. Resistance genes H32 and H24 were originally derived from Ae. tauschii accessions Clae 18 and TA1645. For objectives three and four, we constructed a linkage map of H26 with eight SSR and one TRAP markers. Two other Hessian fly R genes - H24 and H32 - were mapped to the same bin as H26. Mapping populations for identification of H resistance genes were developed. For one of these populations, 11,000 F2 plants were screened. Phenotypic responses of wheat plants carrying each of the mapped H genes were quantified.

Publications


    Progress 10/01/18 to 09/30/19

    Outputs
    Target Audience:The primary target audience is research scientists who share an importantgoal for agriculture:development and deployment of effective and durable genetically-basedresistance to wheat pests and diseases. Scientists pursuing this goal are:entomologists (insects), acarologists (mites), nematologists (nematodes), plant pathologists (fungi and bacteria), wheat breeders, and specialists in plant genetics, genomics and molecular biology. Theshared focus that brings us togetheris a set of resources for plant protection that wheat, as a major crop, has in abundance. These areplantResistancegenes. Wheat has at least 470 documented so-called Resistance (R) genes (Harris et al. 2015) that provide protection against viruses, bacteria, fungi, nematodes, insects and mites. More than ten Resistance genes for disease resistancehave been cloned. No genes for protecting wheat against insect, mite or nematodes have been cloned.There are three questions for researchers whose goal is deployment of Resistance genes for protection of wheat against the various agents of biotic stress. Do any of the already known Resistance genes that confer resistance to a specific disease or pest also have effects - either beneficial or harmful - for protecting wheat against different diseases or pests? Has wheat resistance to each disease or pest arisen independently over evolutionary time or are the various types of resistance in some way related? What is the best method to discover additional novel Resistance genes, i.e. expand genetic resources for protecting wheat? For the third question, studying the molecules secreted by diseases and pests that trigger Resistance gene-mediated plant defense responses is a proven method for discovering new Resistance genes. Changes/Problems:In Spring of 2016 - soon after our five-year research project began - the North Dakota State University plant pathologist faculty member that we planned to collaborate with to see if R genes for stem rust (Puccinia triticina) have any effect on Hessian fly and vice versa departed our university to take a job with the Gates Foundation at Cornell University. She has not been replaced. In the absence of on-campus expertise in stem rust, we expanded our current collaboration with Dr Steven Xu (USDA-ARS, Fargo) to include one of three questions addressed in our original proposal: What is the best method to discover additional novel Resistance genes, i.e. expand genetic resources for protecting wheat? The expertise of Dr Steven Xu is in cytogenetics of wheat resistance to diseases and pests. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?In 2020, we will continue to collaborate with Dr Steven Xu to characterize resistance traits to Hessian fly originating from Ae. tauschii. We expect to prepare several manuscripts based on this research.

    Impacts
    What was accomplished under these goals? Aegilops tauschii Cosson (2n = 2x = 14, DD genome), a diploid goatgrass and the D-genome donor of bread wheat (Triticum aestivum L., 2n = 6x = 14, AABBDD), provides a vast reservoir of genetic variation for potential improvement of bread wheat varieties for both disease and pest resistance. Conferring resistance to Hessian fly (Mayetiola destructor Say), an important insect pest attacking wheat crops in the Middle East, North America, and Asia, are six Ae. tauschii resistance genes (H13, H22, H23, H24, H26, and H32). We are identifying and characterizing Hessian fly resistance genes among a world core collection of Ae. tauschii accessions deposited in the USDA-ARS National Small Grains Collection (NSGC, Aberdeen, ID) and Wheat Genetics Resource Center (WGRC, Manhattan, KS). To identify the resistance, we evaluated approximately 600 Ae. tauschii accessions from NSGC and WGRC for reactions to Hessian fly biotype Great Plain (GP) and identified 90 resistant accessions. To identify potentially novel genes, we conducted fine mapping of the resistance genes in three Ae. tauschii accessions (CIae 25, RL 5271, and TA 2377), which were all highly resistant, killing 100% of larvae during early colonization. Two tightly-linked resistance genes were identified from CIae 25 and mapped to the H26 region on the long arm of chromosome 3D using a large F2 population from the cross between CIae 25 and a susceptible accession AL8/78. The resistance genes in RL 5271 and TA 2377 were both mapped onto the genomic region harboring H13 (6DS) using the two large F2 populations from the crosses RL 5271 × AL8/78 and TA 2377 × AL8/78, respectively. By surveying the genomic sequences of approximately 260 Ae. tauschii accessions, we identified several candidate genes in RL 5271 and TA 2377. Sequence analysis revealed that one candidate gene is nearly identical to the H13 gene in the near isogenic wheat line 'Molly', except for two single-nucleotide mutations, indicating that the Hessian fly resistance gene in RL 5271 and TA 2377 is likely a new haplotype of H13. From the fine mapping analysis, several simple sequence repeat (SSR) and semi-thermal asymnmetric reverse PCR (STARP) markers were identfied to co-segrgate with or tightly linked to these targeted genes. The resistant Ae. tauschii accessions, the resistance genes, and the molecular markers identified in this study provide useful resources for developing durable resistant cultivars and cloning resistance genes for Hessian fly.

    Publications

    • Type: Journal Articles Status: Published Year Published: 2019 Citation: Anderson, K.M. and Harris, M.O. 2019. Susceptibility of North Dakota Hessian fly (Diptera: Cecidomyiidae) to 31 H genes mediating wheat resistance. Journal of Economic Entomology. 112: 2398-2406.


    Progress 10/01/17 to 09/30/18

    Outputs
    Target Audience:The primary target audience is research scientists who share an importantgoal for agriculture:development and deployment of effective and durable genetically-basedresistance to wheat pests and diseases. Scientists pursuing this goal are:entomologists (insects), acarologists (mites), nematologists (nematodes), plant pathologists (fungi and bacteria), wheat breeders, and specialists in plant genetics, genomics and molecular biology. Theshared focus that brings us togetheris a set of resources for plant protection that wheat, as a major crop, has in abundance. These areplantResistancegenes. Wheat has at least 470 documented so-calledResistance(R) genes (Harris et al. 2015) that provide protection against viruses, bacteria, fungi, nematodes, insects and mites. More than tenResistancegenes for disease resistancehave been cloned. No genes for protecting wheat against insect, mite or nematodes have yet been cloned.There are three questions for researchers whose goal is deployment ofResistancegenes for protection of wheat against the various agents of biotic stress. Do any of the already knownResistancegenes that confer resistance to a specific disease or pest also have effects - either beneficial or harmful - for protecting wheat against different diseases or pests? Has wheat resistance to each disease or pest arisen independently over evolutionary time or are the various types of resistance in some way related? What is the best method to discover additional novelResistancegenes, i.e. expand genetic resources for protecting wheat? For the third question, studying the molecules secreted by diseases and pests that triggerResistancegene-mediated plant defense responses is a proven method for discovering newResistancegenes. Changes/Problems:In Spring of 2016, the North Dakota State University plant pathologist faculty member with responsibility for wheat leaf rust (Puccinia triticina) left to take a job with the Gates Foundation at Cornell University. She has not been replaced. There is now a hiring freeze in place in our state university system. To make up for this absence of expertise for our research project, we expanded our current collaboration with Dr Steven Xu (USDA-ARS, Fargo) to include the three questions addressed in our original proposal: Do any of the already knownResistancegenes that confer resistance to a specific disease or pest also have effects - either beneficial or harmful - for protecting wheat against different diseases or pests? Has wheat resistance to each disease or pest arisen independently over evolutionary time or are the various types of resistance in some way related? What is the best method to discover additional novelResistancegenes, i.e. expand genetic resources for protecting wheat? The expertise of Dr Steven Xu is in cytogenetics of wheat resistance to diseases and pests. Our research project has therefore switched its emphasis from phenotyping wheat defense responses to biotic stress to genotyping theResistancegenes that enable the defense responses. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?In 2019, we will continue to collaborate with Dr Steven Xu in: 1) fine-mapping of sixHgenes originating from Ae.tauschii, 2) development of genetic marker loci for use in wheat breeding programs, 3) development of near-isogenic lines (NILs) carrying theH26gene, 4) transferringH26into North Dakota-adapted elite hard red spring wheat cultivars, and 5) continuing the process of cloningH26, with this enabling functional characterization of the gene.

    Impacts
    What was accomplished under these goals? Work in 2018 followed on from discoveries made in 2017, when we tested, in collaboration with the laboratory of Dr Steven Xu (USDA-ARS, Fargo), phenotypic responses of four stem rust strains to stem rust (Puccinia graminisf. sp.tritici; strainsTMLKC, gb121, RKQQC and QFCSC) colonizing33 Hessian fly resistant germplasm lines carrying one or twoHResistancegenes:H1/H2, H3, H4, H5, H6, H7/H8, H9, H10, H11, H12, H13, H14, H15, H16, H17, H18, H19, H20, H21, H22, H23, H24, H25,two lines ofH26, H27, H28, H29, H30, H31, H32andHdic.One of theH26lines (SW8) tested in 2017 had very high levels of resistance to all four races of stem rust tested. What was not clear was whether this was because ofH26itself or because SW8 carries two stem rust resistance genes -Sr13andSr46.In 2017,H32was another wheat genotype that exhibited very high levels of resistance (IT = zero). BothH26andH32originate from an ancestor of wheat,Aegilops tauschii. Both are located on the long arm of bread wheat chromosome 3 of the D genome (3DL). A thirdHgene,H24, is also found on the 3DL. In 2018, we assisted Dr Stephen Xu's lab with fine-mapping ofHgenes fromAe. tauschii,includingH24, H26, H32on the long arm of chromosome 3D (3DL),H22on the short arm of bread wheat chromosome 1D (1DS), andH23andH13on theshort arm of bread wheat chromosome 6D (6DS). Genetic marker data generated from fine-mapping are being used to determine if each gene is unique or related to some otherResistancegene.

    Publications

    • Type: Journal Articles Status: Published Year Published: 2018 Citation: Giron, D., Dubreuil, G., Bennett, A., Dedeine, F., Dicke, M., Dyer, L., Erb, M., Harris, M.O., Huguet, E., Kaloshian, I., Kawakita, A., Lopez-Valmonde, C., Palmer, T., Petanidou, T., Poulsen, M., Sallé, A., Simon, J-C., Terblanche, J.S., Thiery, D., Whiteman, N.K., Woods, H.A., and Princebourde, S. 2018. Promises and challenges in insect-plant interactions. Entomologia Experimentalis et Applicata 166: 319-343. DOI: 10:1111/ee12679. Ali Al-jbory, K.S. Anderson, M.O. Harris, O. Mittapalli, R.J. Whitworth, and M-S. Chen. 2018. Transcriptomic analyses of secreted proteins from the salivary glands of wheat midge larvae. Journal of Insect Science 18: 17 doi: 10.1093/jisesa/iey009


    Progress 10/01/16 to 09/30/17

    Outputs
    Target Audience:The primary target audience is research scientists of several disciplines who share an importantgoal for agriculture:development and deployment of effective and durable genetically-basedresistance to wheat pests and diseases. The disciplines are:entomology (insects), acarology (mites), nematology (nematodes), plant pathology (fungi and bacteria), plant and animal genetics, genomics and molecular biology, and wheat breeders. Theshared focus that brings us togetheris a set of resources for plant protection that wheat, as a major crop, has in abundance. These areplantResistancegenes. Wheat has at least 470 documented Resistance genes (Harris et al. 2015) that provide protection against viruses, bacteria, fungi, nematodes, insects and mites. At least ten for disease resistancehave been cloned. None have been cloned for insect, mite or nematode wheat resistance. Changes/Problems:The NDSU plant pathologist that we were collaborating with left NDSU in Spring 2016, taking a job with the Gates Foundation at Cornell University. She has not been replaced and there is now a hiring freeze in place in our state university system. Because of this, we decided in 2017 to abandon leaf rust (Puccinia triticina) as our exemplar wheat biotroph and switch to stem rust (Puccinia graminis f. sp. tritici). Our collaborator, Dr Steven Xu (USDA-ARS, Fargo) has a research program on stem rust. He was able to provide testing of four stem rust strains, as well as the expertise of a research technician who is highly skilled in scoring stem rust phenotypic responses to wheat resistance genes. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?"Plant Galls Induced by Insects: Lessons from Plant Galls Induced by Bacteria", M.O. Harris, 16th Symposium on Insect-Plant Relationships, Session "Insect Effectors and Plant Responses", Tours, France, 2-6 July 2017. What do you plan to do during the next reporting period to accomplish the goals?In 2018, we will continue our investigations for the second objective,testing Hessian fly resistant near-isogenic lines expressing H genes for responses tostem rust.Five Hessian fly resistant wheat genotypes exhibited very high levels of resistance to stem rust (IT = zero): genotypes carrying H15, H19, H31, H32, or H. dic. We will collaborate with Dr Steven Xu's lab to check each of these lines for stem rust resistance genes (Sr genes). Dr Xu's lab has good molecular markers that can detect many of the Sr genes. If any of the five wheat lines does not appear to carry known Sr genes, we will investigate the possibility that stem rust resistance is associated with the particular H gene that is carried by the wheat line.

    Impacts
    What was accomplished under these goals? Objective Two is to "Determine if wheat Resistance genes that protect against the Hessian fly have any effect on wheat's protection against pathogens." In 2017, we tested reactions to stem rust (Puccinia graminis f. sp. tritici) for one susceptible line (Newton) and 33 Hessian fly resistant germplasm lines carrying one or two H genes. Four races of stem rust were tested: TMLKC, gb121, RKQQC and QFCSC (A-48). The least virulent of the stem rust races is gb121. The Hessian fly resistance genes that were tested were: H1/H2, H3, H4, H5, H6, H7/H8, H9, H10, H11, H12, H13, H14, H15, H16, H17, H18, H19, H20, H21, H22, H23, H24, H25, two lines of H26, H27, H28, H29, H30, H31, H32 and Hdic. Infection type (IT) was scored as 0, 1, 2, 3 or 4, with zero meaning no visible symptom. Typically, five plants were tested for each of the wheat genotype x stem rust race combinations (n = 136); however, in some cases, when seed germination was poor, only 1 or 2 plants were tested. Five wheat genotypes exhibited very high levels of resistance (IT = zero): genotypes carrying H15, H19, H31, H32, or H. dic. One of the H26 lines (SW8) had very high levels of resistance to the four races of stem rust tested but this is probably because it carries two stem rust resistance genes: Sr13 and Sr 46. The H26 line (Jori) had moderate resistance to stem rust (IT2) but is likely to carry two stem rust resistance genes (Sr31 and Sr24) that are common genes in winter wheat and that are known to condition resistance levels of IT2.

    Publications

    • Type: Book Chapters Status: Published Year Published: 2017 Citation: Harris, M.O., J.J. Jens, P. Brown, and G. Yan (2017) Wheat pests: introduction, rodents and nematodes, in P. Langridge (ed.), Achieving sustainable cultivation of wheat Volume 1: Breeding, quality traits, pests and diseases, 2017, Burleigh Dodds Science Publishing, Cambridge, UK (ISBN: 978 1 78676 016 6; www.bdspublishing.com), pp. 443-466. Harris, M.O., K. Anderson, M. El-Bouhssini, F. Peairs, G. Hein, and S. Xu (2017) Wheat pests: insects, mites and prospects for the future in P. Langridge (ed.), Achieving sustainable cultivation of wheat Volume 1: Breeding, quality traits, pests and diseases, 2017, Burleigh Dodds Science Publishing, Cambridge, UK (ISBN: 978 1 78676 016 6; www.bdspublishing.com), pp. 467-544.


    Progress 11/25/15 to 09/30/16

    Outputs
    Target Audience:The primary target audience is research scientists of several disciplines who share an importantgoal for agriculture:development and deployment of effective and durable genetically-basedresistance to wheat pests and diseases. The disciplines are:entomology (insects), acarology (mites), nematology (nematodes), plant pathology (fungi and bacteria), plant and animal genetics, genomics and molecular biology, and wheat breeders. Theshared focus that brings us togetheris a set of resources for plant protection that wheat, as a major crop, has in abundance. These areplantResistancegenes. Wheat has at least 470 documented Resistance genes (Harris et al. 2015) that provide protection against viruses, bacteria, fungi, nematodes, insects and mites. At least tendisease Resistancegenes have been cloned. None have been cloned for insect, mite or nematode resistance. Changes/Problems:The NDSU plant pathologist that we were collaborating with left NDSU in Spring 2016, taking a job at Cornell University. She may not be replaced immediately. However, theresearch technician in the NDSU leaf rust labis able to provide assistance forthe other objectives:1) testing Hessian fly resistant near-isogenic lines expressing H genes against leaf rust, 2) for the Thatcher Lr lines, a 2 x 2 factorial design with absence/presence of bothleaf rust and Hessian flyresistant lines, and 3) for the near-isogenic H lines,a 2 x 2 factorial design with absence/presence of bothleaf rust and Hessian flyresistant lines. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Plenary Talk: "Systems Biology Framework for Understanding How Agricultural Plants Integrate Responses to Biotic Stress", M.O. Harris, Meeting: International Plant Resistance to Insects (IPRI), Stellenbosch, South Africa, 6-8 March 2016. What do you plan to do during the next reporting period to accomplish the goals?In 2017, we will carry out experiments for the second objective,testing Hessian fly resistant near-isogenic lines expressing H genes for responses toleaf rust.

    Impacts
    What was accomplished under these goals? Objective One is to determine if Resistance genes that protect against wheat pathogens have any effect, negative or positive, on protection against wheat pests. Wheat leaf rust Puccini triticina is our model wheat pathogen. Hessian fly Mayetiola destructor is our model wheat pest. Resistance to leaf rust is conferred by at least 79 Lr Resistance genes, which are of two types. One type is race-specific. The other is non-race-specific. Race-specific genes are usually more effective but less durable than non-race-specific genes. Near isogenic Thatcher wheat lines comprise a valuable resource for studying resistance to leaf rust. We obtained small samples of 42 Thatcher lines, one without a Lr gene and the other 41 expressing a single Lr gene. The 41 resistant Thatcher lines mostly expressed race-specific genes but three lines expressed non-race-specific genes: Lr34, Lr46, and Lr67. We infested five plants of each of the 41 resistant lines, plus two susceptible control lines, Thatcher and Newton. None of the resistant Thatcher lines were resistant to egg laying by Hessian fly females. All supported larval colonization, growth, and development to the adult reproductive stage. Growth responses of Thatcher lines to Hessian fly attack were typical of susceptible wheat lines. Seedling growth was stunted soon after larval attack began. Death of seedlings also was observed.

    Publications

    • Type: Journal Articles Status: Published Year Published: 2016 Citation: Guiguet, A., G. Dubreuil, M.O. Harris, H.M. Appel, J.C. Schultz, M.H. Pereira, and D. Giron. 2016. Shared weapons of blood- and plant-feeding insects: surprising commonalities for manipulating hosts. J. Insect Physiology 84: 4-21.
    • Type: Book Chapters Status: Accepted Year Published: 2017 Citation: Harris, M.O., J.J. Jens, P. Brown, and G. Yan. Wheat pests: introduction, rodents and nematodes. In: P. Langridge (Ed.), Achieving Sustainable Wheat Cultivation, Burleigh-Dodds, UK.
    • Type: Book Chapters Status: Accepted Year Published: 2017 Citation: Harris, M.O., K. Anderson, M. El-Bouhssini, F. Peairs, G. Hein, and S. Xu. Wheat pests: insects, mites, and prospects for future pest management. In: P. Langridge (Ed.), Achieving Sustainable Wheat Cultivation, Burleigh-Dodds, UK.