Fusarium wilt, caused by Fusarium oxysporum. f. sp. vasinfectum (FOV) race 4 (FOV4), is a vascular disease and an emerging threat to cotton production in the US Cotton Belt. After the first report of FOV4 in California in 2001 and in Far-west Texas in 2017, a survey of > 600 cotton fields in South New Mexico in 2018 identified FOV4 in more than 10 fields. However, there was a lack of information on the pathology of FOV4, screening methods, sources of FOV4 resistance in tetraploid Upland cotton (Gossypium hirsutum), resistant cultivars, and genetic and genomic basis of resistance. The objective of this review is to summarize research progress in relevant areas with a focus on our success as exemplified from the productive collaboration between breeders and pathologists from New Mexico State University and Texas A&M University. Since 2018, > 6000 cotton breeding lines have been evaluated for FOV4 resistance in the greenhouse and a FOV4-infested field in Fabens, Texas, leading to identification of new sources of FOV4 resistance (presumably from Fw1 in Upland and a major QTL on A11 in diploid Asiatic cotton). Several FOV4 resistant breeding lines (possessing Fov7/Fw2) with high yields and good fiber quality were developed through repeated single plant selection and progeny tests. We were the first to compare the infection process among two resistant lines of different genetic sources (carrying Fov4 and Fov7/Fw2) and susceptible lines. Reliable evaluation methods in the field, greenhouse, and growth chambers were developed through studies on optimal temperature, inoculation density, planting date, cotton growth stage including seed germination, root wounding, experimental designs, and evaluation parameters. We have performed linkage mapping and genome-wide association study (GWAS) for FOV4-resistance QTLs. We have recently demonstrated that the FOV7 resistance gene Fov7 (previously named Fw2 and FwR) with the underlying GhGLR4.8A gene on chromosome D03 also confers resistance to FOV4 in Upland cotton. The previously released three FOV4-resistant Upland cultivars (NuMex COT 15 GLS, NuMex COT 17 GLS, and Acala 1517-20) carried Fov7/Fw2. This led to the development of portable markers through both genotyping-by-targeted sequencing, allele-specific (AS) PCR-based SNP typing, and Kompetitive allele specific PCR (KASP) genotyping and used in marker-assisted selection (MAS). Our comprehensive research activities on FOV4 have led to the publication of 37 refereed journal articles including four first reports of different Fusarium spp. infecting cotton, which has paved the way in identifying and utilizing a complete set of FOV4 resistance genes for breeding through an integrated genetic and genomic approach.

Resistance to Fusarium wilt race 4 in cotton: evaluation methods, germplasm evaluation, breeding, and genetic and genomic studies from a breeder’s perspective

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发表日期：

2026年5月7日

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Yi Zhu,
Terry Wheeler,
Jane Dever,
Jinfa Zhang

摘要

Fusarium wilt, caused by Fusarium oxysporum. f. sp. vasinfectum (FOV) race 4 (FOV4), is a vascular disease and an emerging threat to cotton production in the US Cotton Belt. After the first report of FOV4 in California in 2001 and in Far-west Texas in 2017, a survey of > 600 cotton fields in South New Mexico in 2018 identified FOV4 in more than 10 fields. However, there was a lack of information on the pathology of FOV4, screening methods, sources of FOV4 resistance in tetraploid Upland cotton (Gossypium hirsutum), resistant cultivars, and genetic and genomic basis of resistance. The objective of this review is to summarize research progress in relevant areas with a focus on our success as exemplified from the productive collaboration between breeders and pathologists from New Mexico State University and Texas A&M University. Since 2018, > 6000 cotton breeding lines have been evaluated for FOV4 resistance in the greenhouse and a FOV4-infested field in Fabens, Texas, leading to identification of new sources of FOV4 resistance (presumably from Fw₁ in Upland and a major QTL on A11 in diploid Asiatic cotton). Several FOV4 resistant breeding lines (possessing Fov7/Fw₂) with high yields and good fiber quality were developed through repeated single plant selection and progeny tests. We were the first to compare the infection process among two resistant lines of different genetic sources (carrying Fov4 and Fov7/Fw₂) and susceptible lines. Reliable evaluation methods in the field, greenhouse, and growth chambers were developed through studies on optimal temperature, inoculation density, planting date, cotton growth stage including seed germination, root wounding, experimental designs, and evaluation parameters. We have performed linkage mapping and genome-wide association study (GWAS) for FOV4-resistance QTLs. We have recently demonstrated that the FOV7 resistance gene Fov7 (previously named Fw₂ and Fw^R) with the underlying GhGLR4.8^A gene on chromosome D03 also confers resistance to FOV4 in Upland cotton. The previously released three FOV4-resistant Upland cultivars (NuMex COT 15 GLS, NuMex COT 17 GLS, and Acala 1517-20) carried Fov7/Fw₂. This led to the development of portable markers through both genotyping-by-targeted sequencing, allele-specific (AS) PCR-based SNP typing, and Kompetitive allele specific PCR (KASP) genotyping and used in marker-assisted selection (MAS). Our comprehensive research activities on FOV4 have led to the publication of 37 refereed journal articles including four first reports of different Fusarium spp. infecting cotton, which has paved the way in identifying and utilizing a complete set of FOV4 resistance genes for breeding through an integrated genetic and genomic approach.