Location: Sunflower and Plant Biology ResearchTitle: Registration of HA-R14, HA-R15, HA-R16, and HA-R17 oilseed sunflower germplasms with broad resistance to rust and downy mildew
|MA, GUOJIA - North Dakota State University|
Submitted to: Journal of Plant Registrations
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/19/2021
Publication Date: 10/13/2021
Citation: Qi, L., Ma, G., Seiler, G.J. 2021. Registration of HA-R14, HA-R15, HA-R16, and HA-R17 oilseed sunflower germplasms with broad resistance to rust and downy mildew. Journal of Plant Registrations. 16:137–146. https://doi.org/10.1002/plr2.20187.
Interpretive Summary: Rust and downy mildew (DM) are two of the most important yield-limiting sunflower diseases globally. There has been a long history of using resistant varieties or hybrids to control rust and DM in sunflower. However, resistance is generally not durable due to the emergence of new pathotypes that overcome current resistance sources. Stacking more than one resistance gene (R gene) in a hybrid is expected to considerably extend the durability of resistance due to the low probability of the pathogen being able to overcome multiple resistance genes at the same time. The four germplasms, HA-R14, HA-R15, HA-R16, and HA-R17 were developed to stack different rust resistance genes, with the first three also combining a DM resistance gene. These germplasms will provide a broad spectrum of useful sources of resistance to all modern pathotypes of rust and DM.
Technical Abstract: Rust caused by the fungus Puccinia helianthi Schwein. and downy mildew (DM) caused by the obligate pathogen Plasmopara halstedii (Farl.) Berl. et. de Toni are two of the most important sunflower diseases in the world. The development of sunflower hybrids with enhanced levels of genetic resistance to both diseases is an ultimate goal for sunflower breeding. Four oilseed sunflower (Helianthus annuus L.) germplasms, HA-R14 (Reg. No. ______, PI 698193), HA-R15 (Reg. No. ______, PI 698194), HA-R16 (Reg. No. ______, PI 698195) and HA-R17 (Reg. No. ______, PI 698196) are multiple rust- and DM-resistant germplasm lines that were developed and released by the USDA-ARS, Sunflower and Plant Biology Research Unit in collaboration with the North Dakota Agricultural Experiment Station in January 2020. Three lines, HA-R14 (R4R4/R12R12/PlArgPlArg), HA-R15 (R5R5/R12R12/PlArgPlArg), and HA-R16 (R13bR13b/R12R12/PlArgPlArg) stack two different rust genes with a common DM gene PlArg, and HA-R17 (R13bR13b/R15R15) possesses only two rust genes, R13b and R15. These germplasms will provide a broad spectrum of useful sources of resistance to all known races of rust and DM.