The role of helper NB-LRRs in late blight resistance
toon extra info.
|[S.l.] : [s.n.]|
|III, 36 p|
|Msc Thesis||MSc Thesis Plant Breeding - Plant Biotechnology - Plant Breeding - Wageningen University|
|Trefwoorden (cab)||aardappelen / vuur (plantenziektekundig) / plantenziekten / resistentie van variëteiten / cisgenese / moleculaire veredeling / genetische modificatie / solanum tuberosum / plantenziekteverwekkende schimmels / phytophthora infestans / ziekteresistentie|
|Aardappelen / Moleculaire veredeling|
|Toelichting (Engels)||Late blight is economically the most important disease in potato. A novel approach to produce resistant cultivars is the introduction of R genes into cultivars by using cisgenesis. The success of this approach depends on the background of the receiving cultivars. In a previous project, transformation with Rpi-chc1 led to resistance in Desiree, but not in Premiere. One explanation for this could be a difference in the presence or absence of ‘helper’ NB-LRRs. In this study, to explain the background dependent success of introducing R genes into potato, the requirement and diversity of NRCs in potato and N. benthamiana was studied. This was done by mining for allelic variants of NRCs in potato and by performing Virus Induced Gene Silencing (VIGS) assays and overexpression studies in N. benthamiana. This study shows that different NRCs show different levels of conservedness. Potato, tobacco and N. benthamiana appear to have different numbers of NRC1, NRC2 and NRC3 genes, indicating a different diversification of these genes in these species. The evidence that suggests that Rpi-chc1 requires NRCs to trigger a HR could not be reproduced. However, this study does demonstrate that Rpi-ber might require tobacco NRC3 to trigger a full HR, and that overexpression of tomato NRC3 or potato NRC3 in N. benthamiana reduces the HR triggered by Rpi-ber. The results from this study highlight that it is worth further investigating the diversity of potato NRCs and their importance in R gene triggered resistance.|