Mapping of Two New Rust Resistance Genes <i>Uvf-2</i> and <i>Uvf-3</i> in Faba Bean

• Main Authors: Usman Ijaz, Shimna Sudheesh, Sukhjiwan Kaur, Abdus Sadeque, Harbans Bariana, Urmil Bansal, Kedar Adhikari
• Format: Article
• Language: English
• Published: MDPI AG 2021-07-01
• Series: Agronomy
• Subjects: faba bean; rust resistance; molecular mapping; marker-assisted selection
• Online Access: https://www.mdpi.com/2073-4395/11/7/1370

Faba bean is gaining attention in Australia as a rotation grain legume where most of the country’s produce is exported. Rust, caused by <i>Uromyces viciae-fabae</i>, is a major constraint to Faba bean production in eastern Australia and its chemical control results in increased cost of production. The deployment of diverse sources of resistance in new cultivars underpins economic and eco-friendly control of rust diseases of crops. A selection from cultivar Doza (Doza#12034) and a European accession Ac1655 exhibited seedling rust resistance against <i>U. viciae-fabae</i> pathotype 24–40. Doza#12034 and Ac1655 were crossed with a susceptible genotype Fiord and recombinant inbred line (RIL) F₆ populations were generated. Rust tests on Fiord/Doza#12034 and Fiord/Ac1655 F₄ and F₆ populations demonstrated monogenic inheritance of resistance in both crosses and the underlying resistance loci were named <i>Uvf-2</i> and <i>Uvf-3</i>, respectively. Genetic mapping of both RIL populations located <i>Uvf-2</i> and <i>Uvf-3</i> in chromosomes III and V, respectively. The SNPs that showed linkage with <i>Uvf-2</i> and <i>Uvf-3</i> were converted into kompititive allele specific PCR (KASP) assays. Markers <i>KASP_Vf_0703</i> and <i>KASP_C250539</i> flanked <i>Uvf-2</i> at 4.9 cM and 2.9 cM distances, whereas <i>Uvf-3</i> was flanked by <i>KASP_Ac</i>×<i>F165</i> (2.5 cM) and <i>KASP_vf_1090</i> (10.1 cM). Markers <i>KASP_Vf_0703</i> and <i>KASP_Ac×F165</i> can be used for marker-assisted selection of <i>Uvf-2</i> and <i>Uvf-3,</i> respectively, after confirming parental polymorphisms.