Registration of MNR434 and MNR527 wheat germplasm with new resistance to rusts

Authors: ZHANG, HONGTAO - Montana State University; NYAMESORTO, BERNARD - Montana State University; GIROUX, MICHAEL - Montana State University; Jin, Yue; Chen, Xianming; HUANG, LI - Montana State University

Submitted to: Journal of Plant Registrations
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/2/2019
Publication Date: 9/1/2019
Citation: Zhang, H., Nyamesorto, B., Giroux, M.J., Jin, Y., Chen, X., Huang, L. 2019. Registration of MNR434 and MNR527 wheat germplasm with new resistance to rusts. Journal of Plant Registrations. 13(3):461-464. https://doi.org/10.3198/jpr2019.03.0011crg.
DOI: https://doi.org/10.3198/jpr2019.03.0011crg

Interpretive Summary: Rust diseases of wheat, including leaf rust , stem rust and stripe rust, threaten wheat production worldwide. Incorporating rust resistance is one of the indispensable components in wheat breeding programs. Two wheat lines, MNR434 (PI 689521) and MNR527 (PI 689522) were registered as new sources of rust resistance germplasm. These two wheat lines were developed via chemical mutagenesis of cultivar 'Alpowa' that was susceptible to rust diseases. The rust resistance was identified after screening a mutation population using an isolate of the stem rust pathogen that was virulent to the wild type. The resistant selections were backcrossed to Alpowa to generate near-isogenic lines. Line MNR434 has shown new resistance to stem rust, leaf rust and stripe rust. Line MNR527 has new resistance to stem and stripe rusts, but not leaf rust. The mutations that conferred new rust resistance had no significant yield penalty compared to its wild type allele in a near isogenic background under greenhouse or field condition. These germplsam will be very valuable as new sources of rust resistance for wheat breeding programs.

Technical Abstract: We register MNR434 (PI 689521) and MNR527 (PI 689522) as new sources of rust resistance germplasm. These two wheat lines were developed via EMS mutagenesis of Alpowa and identified after stem rust screening using a Puccinia graminis f. sp. tritici isolate virulent to the wild type followed by one backcross to Alpowa and six generations of self-pollination. MNR434 has shown new resistance to all three rusts and MNR527 has new resistance to stem and stripe rusts, but not leaf rust. The mutations that conferred new rust resistant had no significant yield penalty compared to its wild type allele in a near isogenic background under greenhouse or field condition.