Journal of Integrative Agriculture ›› 2014, Vol. 13 ›› Issue (2): 244-254.DOI: 10.1016/S2095-3119(13)60648-6

• 论文 • 上一篇    下一篇

How Specific is Non-Hypersensitive Host and Nonhost Resistance of Barley to Rust and Mildew Fungi?

 Niks R E   

  1. Laboratory of Plant Breeding, Wageningen University, P.O. Box 386, 6700 AJ Wageningen, The Netherlands
  • 收稿日期:2013-07-09 出版日期:2014-02-01 发布日期:2014-02-06
  • 通讯作者: Niks R E, Tel: +31-317-482508, E-mail: rients.niks@wur.nl
  • 作者简介:Niks R E, Tel: +31-317-482508, E-mail: rients.niks@wur.nl
  • 基金资助:

    I gratefully acknowledge the funding of parts of the research reported here by BioExploit, TritNONHOST (ERA-PG), Xunta de Galicia through the program of Angeles Alvariño, Technology Universiti Malaysia, and the Agricultural Research and Education Organization (AREO) and the Ministry of Science Research and Technology of I.R. of Iran.

How Specific is Non-Hypersensitive Host and Nonhost Resistance of Barley to Rust and Mildew Fungi?

 Niks R E   

  1. Laboratory of Plant Breeding, Wageningen University, P.O. Box 386, 6700 AJ Wageningen, The Netherlands
  • Received:2013-07-09 Online:2014-02-01 Published:2014-02-06
  • Contact: Niks R E, Tel: +31-317-482508, E-mail: rients.niks@wur.nl
  • About author:Niks R E, Tel: +31-317-482508, E-mail: rients.niks@wur.nl
  • Supported by:

    I gratefully acknowledge the funding of parts of the research reported here by BioExploit, TritNONHOST (ERA-PG), Xunta de Galicia through the program of Angeles Alvariño, Technology Universiti Malaysia, and the Agricultural Research and Education Organization (AREO) and the Ministry of Science Research and Technology of I.R. of Iran.

摘要: Full nonhost resistance can be defined as immunity, displayed by an entire plant species against all genotypes of a plant pathogen. Interesting biological questions are, whether the genes responsible for the nonhost status of a plant species have a general or a specific effectiveness to heterologous (“nonhost”) pathogens? Is the nonhost resistance to pathogens of plant species that are related to the nonhost based on R-genes or on other types of genes? We study this question in barley (Hordeum vulgare L.), which is a near-nonhost to several rusts (Puccinia) of cereals and grasses. By crosses and selection we accumulated susceptibility and developed an experimental line, SusPtrit, with high susceptibility to at least nine different heterologous rust taxa such as the wheat and Agropyron leaf rusts (P. triticina and P. persistens, respectively). At the microscopic level there is also some variation among barley accessions in the degree that the heterologous wheat powdery mildew (Blumeria graminis f.sp. tritici) is able to form haustoria in epidermal cells. So, also the genetics of the variation in level of nonhost resistance to heterologous mildew fungi can be studied in barley. Our data obtained on mapping populations involving three regular nonhost-immune accessions (Vada, Cebada Capa and Golden Promise) suggest that nonhost resistance is the joined effect of multiple, quantitative genes (QTLs) and very occasionally a major gene (R-gene?) is involved. Most QTLs have effect to only one or two heterologous rusts, but some have a wider spectrum. This was confirmed in a set of QTL-NILs. Those QTL-NILs are used to fine-map the effective genes. In some cases, a QTL region with effectiveness to several heterologous rusts might be a cluster of genes with a more narrow spectrum of effectiveness. Our evidence suggests that nonhost resistance in barley to rust and powdery mildew fungi of related Gramineae is not due to R-genes, but to pathogen species-specific quantitative resistance genes.

关键词: genetics , specificity , basal resistance

Abstract: Full nonhost resistance can be defined as immunity, displayed by an entire plant species against all genotypes of a plant pathogen. Interesting biological questions are, whether the genes responsible for the nonhost status of a plant species have a general or a specific effectiveness to heterologous (“nonhost”) pathogens? Is the nonhost resistance to pathogens of plant species that are related to the nonhost based on R-genes or on other types of genes? We study this question in barley (Hordeum vulgare L.), which is a near-nonhost to several rusts (Puccinia) of cereals and grasses. By crosses and selection we accumulated susceptibility and developed an experimental line, SusPtrit, with high susceptibility to at least nine different heterologous rust taxa such as the wheat and Agropyron leaf rusts (P. triticina and P. persistens, respectively). At the microscopic level there is also some variation among barley accessions in the degree that the heterologous wheat powdery mildew (Blumeria graminis f.sp. tritici) is able to form haustoria in epidermal cells. So, also the genetics of the variation in level of nonhost resistance to heterologous mildew fungi can be studied in barley. Our data obtained on mapping populations involving three regular nonhost-immune accessions (Vada, Cebada Capa and Golden Promise) suggest that nonhost resistance is the joined effect of multiple, quantitative genes (QTLs) and very occasionally a major gene (R-gene?) is involved. Most QTLs have effect to only one or two heterologous rusts, but some have a wider spectrum. This was confirmed in a set of QTL-NILs. Those QTL-NILs are used to fine-map the effective genes. In some cases, a QTL region with effectiveness to several heterologous rusts might be a cluster of genes with a more narrow spectrum of effectiveness. Our evidence suggests that nonhost resistance in barley to rust and powdery mildew fungi of related Gramineae is not due to R-genes, but to pathogen species-specific quantitative resistance genes.

Key words: genetics , specificity , basal resistance