MOLECULAR MARKERS LINKED TO WHITE RUST RESISTANCE IN MUSTARD BRASSICA-JUNCEA

White rust, caused by Albugo candida (Pers.) Kuntze, is an economicall y important disease of Brassica juncea (L,) Czern. and Coss mustard, p articularly in India. The most efficient and cost-effective way of pro tecting mustard plants from white rust disease is through genetic resi stance. The objective of this study was to identify RAPD markers for w hite rust resistance in an F-1-derived doubled-haploid (DH) population originating from a cross between white rust-susceptible and white rus t-resistant breeding lines of B. juncea from the canola-quality B. jun cea breeding project of the Agriculture and Agri-Food Canada-Saskatoon Research Centre. The DH population was used to screen for RAPD marker s associated with white rust resistance/susceptibility using bulked se gregant analysis. Two markers, WR2 and WR3, linked to white rust resis tance, flanked the resistance locus Ac2(1) and were highly effective i n identifying the presence or absence of the resistance gene in the DH population. These two markers were shown to be specific to the Russia n source of white rust resistance utilized in this project. It is conc luded that the availability of these RAPD markers will enhance the bre eding for white rust resistance in B. juncea.