Does basal PR gene expression in Solanum species contribute to non-specific resistance to Phytophthora infestans?

Abstract Systemic acquired resistance (SAR) occurs in many plant species, including potato. SAR can be induced by various signals, but also basal levels of SAR may vary between plants. In Arabidopsis mutants, basal SAR levels positively correlate with pathogen resistance. Here we test whether in 13 wild Solanum clones and five potato cultivars, basal expression levels of SAR marker genes correlate with resistance to Phytophthora infestans. Most of the examinedSolanum plants displayed significant and variable levels of race/isolate-non-specific, partial resistance to five P. infestans isolates of diverse origin. Constitutive mRNA levels of the pathogenesis-related genes PR-1, PR-2 and PR-5 in non-infected leaves varied between the Solanum clones. However, no correlation between basalPR mRNA levels and resistance was observed at the genus level. In contrast, significant correlation was found at the species level in S. arnezii × hondelmannii, S. microdontum, S. sucrense and S. tuberosum. In S. tuberosum cultivars, the levels of PR gene expression were the highest in resistant Robijn, intermediate in partially resistant Premiere, Estima and Ehud, and the lowest in susceptible Bintje. These results suggest that constitutive expression of PR genes may contribute to non-specific resistance to P. infestans inSolanum . Therefore, PR mRNAs could serve as molecular markers in potato breeding programs.

[1]  P. Hasegawa,et al.  Antifungal activity of tobacco osmotin has specificity and involves plasma membrane permeabilization , 1996 .

[2]  I. Raskin,et al.  Endogenous salicylic acid levels correlate with accumulation of pathogenesis-related proteins and virus resistance in tobacco , 1993 .

[3]  Jean-Pierre Métraux,et al.  Salicylic Acid Induction–Deficient Mutants of Arabidopsis Express PR-2 and PR-5 and Accumulate High Levels of Camalexin after Pathogen Inoculation , 1999, Plant Cell.

[4]  D. Klessig,et al.  A mutation in Arabidopsis that leads to constitutive expression of systemic acquired resistance. , 1994, The Plant cell.

[5]  P. Hasegawa,et al.  Osmotin overexpression in potato delays development of disease symptoms. , 1994, Proceedings of the National Academy of Sciences of the United States of America.

[6]  D. Spooner,et al.  Reexamination of series relationships of South American wild potatoes (Solanaceae: Solanum sect. Petota): evidence from chloroplast DNA restriction site variation. , 1997, American journal of botany.

[7]  Xinnian Dong,et al.  Characterization of an Arabidopsis Mutant That Is Nonresponsive to Inducers of Systemic Acquired Resistance. , 1994, The Plant cell.

[8]  R. Jansen,et al.  CHLOROPLAST DNA EVIDENCE FOR THE INTERRELATIONSHIPS OF TOMATOES, POTATOES, AND PEPINOS (SOLANACEAE) , 1993 .

[9]  A. Stintzi,et al.  Pathogenesis-Related PR-1 Proteins Are Antifungal (Isolation and Characterization of Three 14-Kilodalton Proteins of Tomato and of a Basic PR-1 of Tobacco with Inhibitory Activity against Phytophthora infestans) , 1995, Plant physiology.

[10]  E. Huitema,et al.  Resistance to oomycetes: a general role for the hypersensitive response? , 1999, Trends in plant science.

[11]  A. Bent,et al.  Gene-for-gene disease resistance without the hypersensitive response in Arabidopsis dnd1 mutant. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[12]  C. Pieterse,et al.  Salicylic acid-independent plant defence pathways. , 1999, Trends in plant science.

[13]  D. Klessig,et al.  Characterization of a salicylic acid-insensitive mutant (sai1) of Arabidopsis thaliana, identified in a selective screen utilizing the SA-inducible expression of the tms2 gene. , 1997, Molecular plant-microbe interactions : MPMI.

[14]  S. Wessler,et al.  Molecular identification and isolation of the Waxy locus in maize , 1983, Cell.

[15]  P. Vera,et al.  Two PR-1 genes from tomato are differentially regulated and reveal a novel mode of expression for a pathogenesis-related gene during the hypersensitive response and development. , 1997, Molecular plant-microbe interactions : MPMI.

[16]  F. Govers,et al.  The hypersensitive response is associated with host and nonhost resistance to Phytophthora infestans , 2000, Planta.

[17]  G. Felix,et al.  Resistance to disease in the hybrid Nicotiana glutinosa x Nicotiana debneyi is associated with high constitutive levels of β-1,3-glucanase, chitinase, peroxidase and polyphenoloxidase , 1992 .

[18]  R. Fluhr,et al.  A major stylar matrix polypeptide (sp41) is a member of the pathogenesis‐related proteins superclass. , 1990, The EMBO journal.

[19]  E. Ward,et al.  Increased tolerance to two oomycete pathogens in transgenic tobacco expressing pathogenesis-related protein 1a. , 1993, Proceedings of the National Academy of Sciences of the United States of America.

[20]  L. C. Loon,et al.  The families of pathogenesis-related proteins, their activities, and comparative analysis of PR-1 type proteins , 1999 .

[21]  E. Lam,et al.  Characterization of acquired resistance in lesion-mimic transgenic potato expressing bacterio-opsin. , 1997, Molecular plant-microbe interactions : MPMI.

[22]  F. Govers,et al.  Characterization of a cDNA encoding a pathogenesis-related protein PR-1 from potato (Solanum tuberosum) (Accession No. AJ250136) , 1999 .

[23]  C. Lawrence,et al.  Differential induction of pathogenesis-related proteins in tomato by Alternaria solani and the association of a basic chitinase isozyme with resistance. , 1996 .

[24]  J. Ryals,et al.  Arabidopsis signal transduction mutant defective in chemically and biologically induced disease resistance. , 1995, Proceedings of the National Academy of Sciences of the United States of America.

[25]  A. E. Ainsley,et al.  Genstat 5 Reference Manual , 1987 .

[26]  R. Dixon,et al.  Salicylic acid potentiates an agonist-dependent gain control that amplifies pathogen signals in the activation of defense mechanisms. , 1997, The Plant cell.

[27]  F. Ausubel,et al.  Correlation of defense gene induction defects with powdery mildew susceptibility in Arabidopsis enhanced disease susceptibility mutants. , 1998, The Plant journal : for cell and molecular biology.

[28]  A. Hoekema,et al.  A small-scale procedure for the rapid isolation of plant RNAs. , 1989, Nucleic acids research.

[29]  K. Maleck,et al.  Defense on multiple fronts: how do plants cope with diverse enemies? , 1999, Trends in plant science.

[30]  N. Doke,et al.  Identification of chitinase and osmotin-like protein as actin-binding proteins in suspension-cultured potato cells. , 1997, Plant & cell physiology.

[31]  THH. Chen,et al.  Activation of Two Osmotin-Like Protein Genes by Abiotic Stimuli and Fungal Pathogen in Transgenic Potato Plants , 1995, Plant physiology.

[32]  S. Knapp,et al.  Quantitative resistance to Phytophthora infestans in potato: a case study for QTL mapping in an allogamous plant species. , 1994, Genetics.

[33]  Y. Cohen,et al.  Local and systemic protection against Phytophthora infestans induced in potato and tomato plants by jasmonic acid and jasmonic methyl ester , 1993 .

[34]  N. Doke,et al.  Systemic Induction of Resistance in Potato Plants Against Phytophthora infestans by Local Treatment with Hyphal Wall Components of the Fungus , 1987 .

[35]  T. L. Graham,et al.  Role of hypersensitive cell death in conditioning elicitation competency and defense potentiation , 1999 .

[36]  Y. Cohen,et al.  Systemic resistance of potato plants against Phytophthora infestans induced by unsaturated fatty acids , 1991 .

[37]  Xin Li,et al.  Generation of broad-spectrum disease resistance by overexpression of an essential regulatory gene in systemic acquired resistance. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[38]  C. Woloshuk,et al.  Pathogen-induced proteins with inhibitory activity toward Phytophthora infestans. , 1991, The Plant cell.