Registration of three Gossypium barbadense L. American pima‐like germplasm lines (PSSJ‐FRP01, PSSJ‐FRP02, and PSSJ‐FRP03) with improved resistance to Fusarium wilt race 4 and good fiber quality

Abstract

Over the past 18 yr, Fusarium wilt race 4 (FOV4) has affected cotton (Gossypium spp.) production in the San Joaquin Valley of California, and more recently this pathogen was formally identified in 2017 in the El Paso, TX, region and in 2019 in New Mexico. The primary purpose for the germplasm release is to provide cotton breeders with needed alternative sources for continuing to improve FOV4 resistance in pima cotton. PSSJ-FRP01 (Reg. no. GP-1107, PI 699963) (PS-592) originated from Pima S-6 × G. barbadense pool accessions GB1368/k-7616. Pima S-6 possesses a major gene(s) for FOV4 resistance. GB1368/k-7616 is Uzbekistan accession introduction with different plant structure, large leaves, columnar growth, and a more clustered fruiting habit when compared to most American pima. PSSJ-FRP02 (Reg. no. GP-1108, PI 699964) and PSSJ-FRP03 (Reg. no. GP-1109, PI 699965) originated from PS-592 × SA-3208 (LIAO MIAN 7 HAO). SA-3208 is moderately resistant to FOV4. Multiple selections and recurrent cycles of selections were applied to these new germplasm lines based on an asymptomatic single plant after greenhouse FOV4 inoculations and/or infested field evaluations from F 1 to F 4 . In subsequent field and greenhouse tests in 2019-2021, the germplasm lines showed improved resistance to FOV4 based on low percentage mortality and vascular staining and fiber quality when compared to commercial cultivars. PSSJ-FRP01, PSSJ-FRP02, and PSSJ-FRP03 lines will help to continue reducing the vulnerability of the pima cotton industry to this fungal pathogen and to advance efforts to broaden the genetic base of FOV4 resistance, which is critical to the pima cotton industry in the United States and Uzbekistan.

Registration of 17 upland cotton germplasm lines with improved resistance to Fusarium wilt race 4 and good fiber quality

“…PSSJ-FRP01 is a G. barbadense germplasm line originating from a cross between Pima S-6 and a pima-like Uzbekistan breeding pool (GB1368/k-7616) line and is moderately resistant to FOV4. Pima S-6 is known to possess a major gene(s) for FOV4 resistance (Ulloa et al, 2013(Ulloa et al, , 2022Ulloa, Wang, et al, 2016). The pedigree information for the 17 germplasm lines is summarized in Supplemental Table S1.…”

“…In the early 2000s, in response to FOV4 as a potential production issue in California USDA‐ARS and University of California, with the support of the California Cotton Ginners and Growers Association, California Cotton Alliance, and Cotton Incorporated began evaluations by screenings under infested field conditions of commercial cultivars and germplasm to identify sources of FOV4 resistance (University of California, 2022; Ulloa, Hutmacher, et al., 2006). These efforts led to pima ( Gossypium barbadense L.) germplasm with improved FOV4 resistance (Ulloa, Hutmacher, et al., 2006; Ulloa, Hutmacher, et al., 2016; Ulloa et al., 2020, 2022). However, FOV4 appears to be spreading and represents a major threat, especially because its identification as a pathogen in New Mexico and Texas where upland ( Gossypium hirsutum L.) cultivars predominate (Diaz et al., 2021; Ulloa et al., 2020).…”

Assembly and annotation of the Gossypium barbadense L. ‘Pima-S6’ genome raise questions about the chromosome structure and gene content of Gossypium barbadense genomes

“…Specifically, Pima S-6 was released in 1984 [9], and was used as the source of resistance of highly pathogenic Fusarium oxysporum f. sp. vasinfectum (FOV) race 4 in the first commercial Pima varieties and public germplasm releases in the U.S. [10][11][12][13][14] (see Materials and Methods). FOV is a soil borne fungal pathogen that threatens cotton production around the world, and for over a decade, FOV4 strain has adversely impacted cotton production in the U.S., causing plant wilt and death [10][11][12].…”

“…FOV is a soil borne fungal pathogen that threatens cotton production around the world, and for over a decade, FOV4 strain has adversely impacted cotton production in the U.S., causing plant wilt and death [10][11][12]. Since Pima S-6 identification as a source of FOV4-resistance, it was subjected to several cycles of evaluations and selections under FOV4 infested fields to increase its uniformity and the level of resistance [10][11][12][13][14]. This new selection source was renamed Pima-S6.…”

Targeted development of diagnostic SNP markers for resistance to Fusarium wilt race 4 in Upland cotton (Gossypium hirsutum)

“…In the US, numerous Upland cotton accessions and germplasm lines have been evaluated for FOV4 resistance under the field and/or greenhouse conditions (Ulloa et al 2006, 2020; Hutmacher et al 2013; Abdelraheem et al 2020; Zhang et al 2020a, 2022d). Breeding lines and cultivars with improved FOV4 resistance have been developed and released through germplasm registrations in the public sector (Ulloa et al 2009, 2016, 2022, 2023; Zhang et al 2016, 2020a). However, no DNA markers associated with the resistance in these resistant lines and cultivars have been identified.…”