Targeted mutagenesis of MLO-homologous genes in the rose genome

authored by
J. Geike, H. Kaufmann, F. Schürmann, T. Debener

Powdery mildew caused by Podosphaera pannosa is one of the most severe diseases of roses. Especially for greenhouse production of cut roses it depicts a significant problem. Biology and race structure of P. pannosa limit the effectiveneß of race-specific, monogenic resistances making the application of fungicides indispensable. However, this application is not very desirable because of high costs, increasing legal restrictions and public concerns. An alternative to overcome this problem can be the mildew resistance locus o (mlo)-mediated resistance. The mlobased resistance has been characterized in barley, A. thaliana, tomato and pea where the loß-of-function of specific members of the MLO gene-family leads to a receßive and durable broad-spectrum resistance. In rose four MLO homologs (RhMLO1, RhMLO2, RhMLO3 and RhMLO4) closely related to the functional ones in A. thaliana, pea and tomato have been sequenced and mapped. The aim of this work is a reverse genetics approach to verify the functionality of the four mentioned rose MLOs regarding the mediation of susceptibility towards P. pannosa. Therefore, stable transgenics of the tetraploid Rosa hybrida cultivar 'Pariser Charme' expreßing an RNAi construct for all four genes are produced. Several shoots could be regenerated and transferred to soil and first analyses to determine the transgenic character of the plants have been performed.

Section Molecular Plant Breeding
External Organisation(s)
University Hospital Düsseldorf
Contribution to book/anthology
No. of pages
Publication date
Publication status
Peer reviewed
ASJC Scopus subject areas
Electronic version(s) (Access: Unknown)