Location: Sunflower and Plant Biology ResearchTitle: Registration of two oilseed sunflower germplasms, HA-R18 and HA-R19, resistant to sunflower rust
|MA, GUOJIA - North Dakota State University|
Submitted to: Journal of Plant Registrations
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/26/2022
Publication Date: 7/23/2022
Citation: Qi, L., Ma, G., Seiler, G.J. 2022. Registration of two oilseed sunflower germplasms, HA-R18 and HA-R19, resistant to sunflower rust. Journal of Plant Registrations. 16(3):649-655. https://doi.org/10.1002/plr2.20225.
Interpretive Summary: Oilseed sunflower is ranked the third after soybean and rapeseed in terms of oil production in the world. Sunflower rust is a serious fungal disease in the sunflower growing areas worldwide and can cause losses up to 85% in an epidemic year. Growing resistant sunflower hybrids is the most profitable and environmentally friendly strategy for farmers to control sunflower rust. However, the emergence of new pathogen types has rendered most of the existing rust-resistant inbred lines and the commercial hybrids susceptible to rust, which could lead to epidemics when weather conditions are conductive for disease development. Therefore, it is necessary to discover new rust resistance genes for breeding, and ultimately, long term management of sunflower rust. The current study reported to develop the new sunflower lines, HA-R18 and HA-R19, possessing the new rust resistance genes R17 and R18, respectively. The rust tests indicated that HA-R18 and HA-R19 exhibit resistance to a wide range of rust races currently identified in the United States, providing valuable lines for sunflower breeding programs.
Technical Abstract: Sunflower rust, incited by the fungus Puccinia helianthi Schwein., is a serious fungal disease in the sunflower growing areas worldwide with an increasing importance in North America in recent years due to the frequent evolution of new pathogen races. HA-R18 (Reg. No.xxx, PI 698197) and HA-R19 (Reg. No.xxx, PI 698199) are rust-resistant germplasm lines that were developed and released cooperatively in 2020 by the USDA-ARS, Sunflower and Plant Biology Research Unit and the Agricultural Experiment Station of North Dakota State University. The rust resistance in HA-R18 and HA-R19 originated from KP193 and KP199, respectively, which were identified segregating for rust resistance after screening of 58 sunflower lines introduced from South Africa. Rust evaluation of HA-R18 and HA-R19 with 11 P. helianthi races indicated that both lines exhibited resistance to the most rust races tested including the most predominant and the most virulent races currently identified in the United States. HA-R18 and HA-R19 possess the new rust resistance genes R17 and R18, respectively, both of which have been mapped to sunflower chromosome 13. The two new lines will diversify the pool of rust resistance genes and should serve as useful sources of rust resistance in sunflower.