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The Hessian fly (HF) is an invasive insect that has caused millions of dollars in yield losses to southeastern US wheat farms. Genetic resistance is the most sustainable solution to control HF. However, emerging biotypes are quickly overcoming resistance genes in the southeast; therefore, identifying novel sources of resistance is critical. The resistant line "UGA 111729" and susceptible variety "AGS 2038" were crossbred to generate a population of 225 recombinant inbred lines. This population was phenotyped in the growth chamber (GC) during 2019 and 2021 and in field (F) trials in Georgia during the 2021–2022 growing seasons. Visual scoring was utilized in GC studies. The percentage of infested tillers and number of pupae/larvae per tiller, and infested tiller per sample were measured in studies from 2021 to 2022. Averaging across all traits, a major QTL on chromosome 3D explained 42.27% (GC) and 10.43% (F) phenotypic variance within 9.86 centimorgans (cM). SNP marker IWB65911 was associated with the quantitative trait locus (QTL) peak with logarithm of odds (LOD) values of 14.98 (F) and 62.22 (GC). IWB65911 colocalized with resistance gene H32. KASP marker validation verified that UGA 111729 and KS89WGRC06 express H32. IWB65911 may be used for marker-assisted selection. [ABSTRACT FROM AUTHOR]

Soft red winter wheat (SRWW) (Triticum aestivum L.) production in the southeastern United States is affected by biotic and abiotic stresses that can result in yield losses and reduced acreage. Developing new cultivars with high yield, good resistance to predominant pests, and acceptable quality to maximize value in regional markets is needed. The University of Georgia (UGA) SRWW breeding program, in collaboration with institutions in the region including the Southern UNiversities GRAINS (SUNGRAINS) programs, is responding to these challenges by developing and releasing superior cultivars adapted to the region. 'GA 08535‐15LE29' (Reg. no. CV‐1191, PI 693269) SRWW cultivar was developed and released by the UGA College of Agricultural and Environmental Sciences and licensed to Uni South Genetics seed company in 2018 as USG 3640. GA 08535‐15LE29 is well adapted to Georgia and the U.S. southeast region with high yield and good resistance to leaf (Puccinia triticina Erikss.) and stripe (P. striiformis Westend.) rusts, Fusarium head blight (caused by Fusarium graminearum Schwabe), powdery mildew (Erisyphe graminis), and Soil‐borne wheat mosaic virus (SBWMV) diseases. GA 08535‐15LE29 showed moderate field resistance to Hessian fly [Mayetiola destructor (Say)]. GA 08535‐15LE29 has Sbm1 and Yr17/Lr37/Sr38 for resistance to SBWMV and rust diseases and has good grain volume weight and acceptable milling and baking qualities. Core Ideas: GA 08535‐15LE29 was developed by the University of Georgia in collaboration with SUNGRAINS.GA 08535‐15LE29 is well adapted to Georgia and the U.S. Southeast.GA 08535‐15LE29 is resistant to prevalent diseases (e.g., rusts) and insects (e.g., Hessian fly).GA 08535‐15LE29 possesses Sbm1 and Yr17/Lr37/Sr38 genes/QTL. [ABSTRACT FROM AUTHOR]

Soil-borne wheat mosaic virus (SBWMV) is considered to be one of the most important diseases in winter wheat regions of the central and southeastern United States. Utilization of resistant cultivars is the most efficient and environmentally friendly means of control. To identify potential quantitative trait loci (QTL) or effective gene(s) for SBWMV resistance, two independent recombinant inbred line populations, Pioneer 26R61/AGS 2000 (PR61/A2000, 178 lines) and AGS 2020/LA 95135 (A2020/LA, 130 lines), were developed. Pioneer 26R61 and AGS 2020 were resistant to SBWMV, and AGS 2000 and LA 95135 were susceptible. Based on the whole genome genotyping for the PR61/A2000 population and targeted mapping of chromosome 5D for the A2020/LA, the same major QTL QSbm.uga- 5DL was identified in all environments with highly significant LOD values, explaining up to 62 and 65 % of the total phenotypic variation in the PR61/A2000 and A2020/LA populations, respectively. The location of the resistance QTL coincided with previously published SBCMV resistance genes Sbm1, Sbm and Sbm on the long arm of chromosome 5D. A conserved locus was therefore proposed for conditioning SBWMV/SBCMV resistance in common wheat. Validation of the QTL using the flanking markers Xbarc177 and Xbarc161 in three cultivars and three elite lines with Pioneer 26R61 in their pedigrees indicated that the markers were suitable for marker-assisted selection. [ABSTRACT FROM AUTHOR]