Enhanced late blight resistance of potato shown by siRNA mediated control of pathogen gene expression in greenhouse and field trials
D. STAHL (1), N. Temme (1), C. Blumenhagen (1), T. Sauter (1), L. Hoppe (1), C. Davenport (1), Z. Stumo (2), K. Prenzler (1), M. Pflugmacher (1), K. Koch (1) (1) KWS SAAT SE, Germany; (2) Betaseed, U.S.A.

Late blight caused by Phytophthora infestans is currently the most serious disease of potatoes. Here we present the efficacy of the host-induced gene silencing (HIGS) technology as a strategy to increase the resistance against plant-infecting oomycetes. Hairpin constructs directed against a putative acetolactate synthase (ALS) and the histidine ammonia-lyase (HAL) gene of Phytophthora infestans were both transferred into potato. HIGS-ALS and HIGS-HAL potato lines displayed an efficient target gene silencing. Plant derived siRNA targeting the oomycete’s ALS gene was detected by Northern blot and small RNA sequencing. P. infestans ALS gene expression was reduced during the early stages of HIGS-ALS potato infection. HIGS-ALS plants and HIGS-HAL plants revealed an enhanced late blight resistance in a detached leaf assay. Late blight resistance was confirmed in field trials in the USA and in trials under near-field conditions in Europe against US and European P. infestans isolates, respectively. These results facilitate a novel strategy for improved crop production with reduced fungicide application.

Abstract Number: P20-721
Session Type: Poster