JASMONIC ACID PRIMING OF POTATO USES HYPERSENSITIVE RESPONSE-DEPENDENT DEFENSE AND DELAYS NECROTROPHIC PHASE CHANGE AGAINST PHYTOPHTHORA INFESTANS

SynopsisThe common strain and six specialised strains of Phytophthora infestans have been employed in testing potato varieties and seedling progenies bred from the wild species S. demissum for resistance to the disease. Resistance, due to the hypersensitive condition of the protoplasm, is manifested in the presence of major genes, and four such genes have been identified, viz. R1, R2, R3 and R4. Each gene induces in the plant a hypersensitive response to infection with the common strain and with a particular group of specialised strains of the parasite. The genes are inherited independently in simple Mendelian fashion, but in the segregations three different types of deviations from standard disomic ratios occur due to (a) unpaired chromosomes, (b) incompatibility factors, and (c) partial autosyndesis. A series of minor genes modify the phenotypic expression of the major gene system and so differentiate grades of hypersensitivity or of susceptibility as the case may be.The common strain of P. infestans appears to be a population persisting at an equilibrium determined by host range and environmental conditions. Mutations frequently occur, but new forms survive only when host genotypes, to which they are specially adapted, are available.

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Hypersensitive response in potato tuber: elicitation by combination of non-eliciting components from Phytophthora infestans

Physiological Plant Pathology ◽

10.1016/s0048-4059(81)80055-0 ◽

1981 ◽

Vol 18 (1) ◽

pp. 67-IN8 ◽

Cited By ~ 19

Author(s):

M.J. Kurantz ◽

R.M. Zacharius

Keyword(s):

Potato Tuber ◽

Phytophthora Infestans ◽

Hypersensitive Response

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Differences in Intensity and Specificity of Hypersensitive Response Induction in Nicotiana spp. by INF1, INF2A, and INF2B of Phytophthora infestans

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-18-0183 ◽

2005 ◽

Vol 18 (3) ◽

pp. 183-193 ◽

Cited By ~ 36

Author(s):

Edgar Huitema ◽

Vivianne G. A. A. Vleeshouwers ◽

Cahit Cakir ◽

Sophien Kamoun ◽

Francine Govers

Keyword(s):

Phytophthora Infestans ◽

Hypersensitive Response ◽

Potato Virus X ◽

Class I ◽

Class Iii ◽

Secreted Expression ◽

Phytophthora Spp ◽

Defense Response Genes ◽

Tomato Pathogen ◽

Related Proteins

Elicitins form a family of structurally related proteins that induce the hypersensitive response (HR) in plants, particularly Nicotiana spp. The elicitin family is composed of several classes. Most species of the plant-pathogenic oomycete genus Phytophthor produce the well-characterized 10-kDa canonical elicitins (class I), such as INF1 of the potato and tomato pathogen Phytophthora infestans. Two genes, inf2A and inf2B, encoding a distinct class (class III) of elicitinlike proteins, also occur in P. infestans. Unlike secreted class I elicitins, class III elicitins are thought to be cell-surface- anchored polypeptides. Molecular characterization of the inf2 genes indicated that they are widespread in Phytophthora spp. and occur as a small gene family. In addition, Southern blot and Northern blot hybridizations using gene-specific probes showed that inf2A and inf2B genes and transcripts can be detected in 17 different P. infestans isolates. Functional secreted expression in plant cells of the elicitin domain of the inf1 and inf2 genes was conducted using a binary Potato virus X (PVX) vector (agroinfection) and Agrobacterium tumefaciens transient transformation assays (agroinfiltration), and resulted in HR-like necrotic symptoms and induction of defense response genes in tobacco. However, comparative analyses of elicitor activity of INF1, INF2A, and INF2B revealed significant differences in intensity, specificity, and consistency of HR induction. Whereas INF1 induced the HR in Nicotiana benthamiana, INF2A induced weak symptoms and INF2B induced no symptoms on this plant. Nonetheless, similar to INF1, HR induction by INF2A in N. benthamiana required the ubiquitin ligase-associated protein SGT1. Overall, these results suggest that variation in the resistance of Nicotiana spp. to P. infestans is shadowed by variation in the response to INF elicitins. The ability of tobacco, but not N. benthamiana, to respond to INF2B could explain differences in resistance to P. infestans observed for these two species.

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(—)-Jasmonic Acid Accumulation in Tobacco Hypersensitive Response Lesions

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.1999.12.1.74 ◽

1999 ◽

Vol 12 (1) ◽

pp. 74-78 ◽

Cited By ~ 46

Author(s):

Paul Kenton ◽

Luis A. J. Mur ◽

Rainer Atzorn ◽

Claus Wasternack ◽

John Draper

Keyword(s):

Cell Death ◽

Jasmonic Acid ◽

Pseudomonas Syringae ◽

Hypersensitive Response ◽

Protein Loss ◽

Acid Accumulation

Tobacco infected with Pseudomonas syringae pv. phaseolicola undergoes a hypersensitive response (HR). Jasmonic acid (JA) accumulated within the developing lesion 3 to 9 h after infection and this accumulation preceded protein loss, cell death, and malondialdehyde accumulation. Accumulating JA consisted largely of the (—)-JA stereoisomer and was essentially restricted to the HR lesion.

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