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ARS Home » Southeast Area » Stuttgart, Arkansas » Dale Bumpers National Rice Research Center » Research » Publications at this Location » Publication #426014
Research Project: Broadening and Strengthening the Genetic Base of Rice for Adaptation to a Changing Climate, Crop Production Systems, and Markets

Location: Dale Bumpers National Rice Research Center

Title: Registration of two blast resistant medium grain rice germplasm lines USDA-ARS-GKZ4, USDA-ARS-GKZ61 with improved quality and grain weight

Author
item JIA, YULIN
item JACKSON, AARON
item DUNLAP, HEATHER
item JIA, MELISSA
item EVERETTE, JACE
item SMITH, BRENNAN

Submitted to: Journal of Plant Registrations
Publication Type: Germplasm Registration
Publication Acceptance Date: 8/4/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: Blast disease is one of the most destructive diseases of rice and is managed using major blast resistance genes. USDA-ARS-GKZ4 and USDA-ARS-GKZ61 are blast resistant rice germplasm lines that were developed by the USDA-ARS Dale Bumpers National Rice Research Center, Stuttgart, Arkansas. They were selected from the USDA-ARS released mapping population K/Z consisting of 353 recombinant inbred lines of the tropical japonica–indica cross, Kaybonnet lpa1-1 and Zhe 733. These lines were characterized in Arkansas rice fields during 2017-2022. Blast resistance was determined under greenhouse and field conditions. Under greenhouse conditions, these two germplasm lines were resistant to all common US blast races IA45, IB1, IB49, IB54, IC17, IE1, IG1, IH1, and IE1k. Under naturally infected field conditions in Louisiana and Puerto Rico, they were resistant to both leaf and panicle blast infections. USDA-ARS-GKZ4 has Pi42(t) and Pi43(t) and lacks Pi-ta and Ptr. USDA-ARS-GKZ61 has four broad spectra major blast resistance genes Pi-ta, Ptr, Pi42(t) and Pi43(t). USDA-ARS-GKZ4 has low phytic acid, which can provide nutritional benefits for humans and animals. Both USDA-ARS-GKZ germplasm lines confer a significant reduction in chalkiness relative to the Zhe733 parent of 58.1% or better while maintaining a thousand kernel weight of 13.7% or greater than the Kaybonnet lpa1-1 parent. The USDA-ARS-GKZ lines are useful for improving disease resistance and can also be used directly by growers for rice production.

Technical Abstract: Blast disease caused by the fungus Magnaporthe oryzae B. C. Couch is one of the most lethal diseases of rice and is managed using major blast resistance genes with overlapped resistance spectra. USDA-ARS-GKZ4 and USDA-ARS-GKZ61 are blast resistant rice germplasm lines that were developed by the USDA-ARS Dale Bumpers National Rice Research Center, Stuttgart, Arkansas. They were selected from the USDA ARS released mapping population K/Z consisting of 353 F10–11 generation recombinant inbred lines of the tropical japonica–indica cross, Kaybonnet lpa1-1 Genetic Stocks-Oryza and Zhe 733. These lines were characterized in Arkansas rice fields during 2017-2022. Blast resistance was determined under greenhouse and field conditions. Under greenhouse conditions, these two germplasm lines were resistant to all common US blast races IA45, IB1, IB49, IB54, IC17, IE1, IG1, IH1, and IE1k. Under naturally infected field conditions in Louisiana and Puerto Rico, they were resistant to both leaf and panicle blast infections. USDA-ARS-GKZ4 has Pi42(t) and Pi43(t) and lacks Pi-ta and Ptr. USDA-ARS-GKZ61 has four overlapped broad spectra major blast resistance genes Pi-ta, Ptr, Pi42(t) and Pi43(t). USDA-ARS-GKZ4 has low phytic acid, which can provide nutritional benefits for humans and animals. Both USDA-ARS-GKZ germplasm lines confer a significant reduction in chalkiness relative to the Zhe733 parent of 58.1% or better while maintaining a thousand kernel weight of 13.7% or greater than the Kaybonnet lpa1-1 parent. The USDA-ARS-GKZ lines are useful for improving disease resistance and can also be used directly by growers for rice production.