The secreted PAMP-induced peptide StPIP1_1 activates immune responses in potato.

Treatment of potato plants with the pathogen-associated molecular pattern Pep-13 leads to the activation of more than 1200 genes. One of these, StPIP1_1, encodes a protein of 76 amino acids with sequence homology to PAMP-induced secreted peptides (PIPs) from Arabidopsis thaliana. Expression of StPIP1_1 is also induced in response to infection with Phytophthora infestans, the causal agent of late blight disease.

Lysophosphatidylcholine 17:1 from the Leaf Surface of the Wild Potato Species Inhibits .

Late blight, caused by the oomycete , is economically the most important foliar disease of potato. To assess the importance of the leaf surface, as the site of the first encounter of pathogen and host, we performed untargeted profiling by liquid chromatography-mass spectrometry of leaf surface metabolites of the susceptible cultivated potato and the resistant wild potato species . Hydroxycinnamic acid amides, typical phytoalexins of potato, were abundant on the surface of , but not on .

Early Pep-13-induced immune responses are SERK3A/B-dependent in potato.

Potato plants treated with the pathogen-associated molecular pattern Pep-13 mount salicylic acid- and jasmonic acid-dependent defense responses, leading to enhanced resistance against Phytophthora infestans, the causal agent of late blight disease. Recognition of Pep-13 is assumed to occur by binding to a yet unknown plasma membrane-localized receptor kinase. The potato genes annotated to encode the co-receptor BAK1, StSERK3A and StSERK3B, are activated in response to Pep-13 treatment.

A substrate of the ABC transporter PEN3 stimulates bacterial flagellin (flg22)-induced callose deposition in .

Nonhost resistance of against , a filamentous eukaryotic microbe and the causal agent of potato late blight, is based on a multilayered defense system. controls pathogen entry through the penetration-resistance genes and , encoding an atypical myrosinase and an ABC transporter, respectively, required for synthesis and export of unknown indole compounds. To identify pathogen-elicited leaf surface metabolites and further unravel nonhost resistance in , we performed untargeted metabolite profiling by incubating a zoospore suspension on leaves of WT or mutant plants.

The ABC transporter ABCG1 is required for suberin formation in potato tuber periderm.

The lipid biopolymer suberin plays a major role as a barrier both at plant-environment interfaces and in internal tissues, restricting water and nutrient transport. In potato (Solanum tuberosum), tuber integrity is dependent on suberized periderm. Using microarray analyses, we identified ABCG1, encoding an ABC transporter, as a gene responsive to the pathogen-associated molecular pattern Pep-13.

Characterization of potato plants with reduced StSYR1 expression.

Vesicle fusion processes in plants are important for both development and stress responses. Transgenic potato plants with reduced expression of SYNTAXIN-RELATED1 (StSYR1), a gene encoding the potato homolog of Arabidopsis PENETRATION1 (AtPEN1), display spontaneous necrosis and chlorosis at later stages of development. In accordance with this developmental defect, tuber number, weight and overall yield are significantly reduced in StSYR1-RNAi lines.

Activation of defense against Phytophthora infestans in potato by down-regulation of syntaxin gene expression.

The oomycete Phytophthora infestans is the causal agent of late blight, the most devastating disease of potato. The importance of vesicle fusion processes and callose deposition for defense of potato against Phytophthora infestans was analyzed. Transgenic plants were generated, which express RNA interference constructs targeted against plasma membrane-localized SYNTAXIN-RELATED 1 (StSYR1) and SOLUBLE N-ETHYLMALEIMIDE-SENSITIVE FACTOR ADAPTOR PROTEIN 33 (StSNAP33), the potato homologs of Arabidopsis AtSYP121 and AtSNAP33, respectively.