Breeding, Genetics, and Quantitative Trait Locus Mapping for Fusarium Wilt Resistance in Cotton

Abstract

Fusarium wilt (FW), caused by the soilborne fungus Fusarium oxysporum f. sp. vasinfectum (FOV), with eight races recognized, is one of the most destructive diseases in cotton (Gossypium spp.). Employment of FW‐resistant cultivars has proven to be the most cost‐effective method to control the disease. This review provides a comprehensive synthesis of research progress in breeding, genetics, and molecular mapping of FW resistance. A focused pedigree analysis in Upland cotton (G. hirsutum L.) has identified five major FW‐resistant sources (‘Dillon’, ‘Dixie Triumph’, ‘Cook 307‐6’, ‘Coker Clevewilt’, and ‘Wild’) in the United States and three (‘Chuan 52‐128’, ‘Chuan 57‐681’, and ‘CRI 12’) in China. The use of numerous early segregating populations has consistently confirmed the predominant presence of additive gene effects on FW resistance; however, heritability is usually low because of high experimental error. Several mapping studies have detected approximately 40 quantitative trait loci (QTL) on 19 chromosomes. A number of qualitative genetic studies have identified five major resistance genes in Upland and Pima (G. barbadense L.) cotton including Fw1, Fw2, FwR (chromosome 17), FOV1 (chromosome 16), and FOV4 (chromosome 14). There are other major resistance genes identified through marker or segregating analysis, but methods with high and uniform infection by FOV are required to confirm the results. More differential hosts should be developed to differentiate new races, and more resistance genes from new sources should be identified for their strategic deployment in preventing a possible risk of disease epidemic.

Registration of glandless ‘NuMex COT 17 GLS’ upland cotton cultivar with Fusarium wilt race 4 resistance

“…Breeding for resistant cultivars is the most cost‐effective FW management strategy. As demonstrated in China, breeding upland cotton for resistance to FOV race 7 (FOV7) since the 1950s has resulted in the development of several hundreds of FW‐resistant cultivars, which has essentially controlled FW in cotton production in the country since the mid‐1990s (Zhang, Sanogo, Ma, & Qu, ). Because the main resistance sources for FOV7 in China were direct selections from susceptible American upland cotton cultivars and FOV4 and FOV7 are highly related, the use of FOV7‐resistant Chinese cotton cultivars in breeding may result in development of new upland cotton cultivars with resistance to FOV4.…”

Registration of ‘Acala 1517‐21’ Cotton Cultivar

“…The average severity rating was converted to disease severity index by dividing it with the highest rating of 5, and disease severity index was used for ANOVA and a LSD calculation for each test. In 2018, Acala 1517‐20 was evaluated in the greenhouse for resistance to FOV4 using a foliar symptom severity on a scale of 0–5 (Sanogo & Zhang, 2016; Zhang et al., 2020a; Zhang, Sanogo, Ma, & Qu, 2015), where it was compared with other lines in four replications (10 plants in each replication) through artificial inoculation (with 10 ml of 1 × 10 6 spores ml -1 spores drenched to the soil surface). To screen for resistance to above VW, ALS and FOV4 diseases, the following scale of 0–5 was used based on the entire leaf canopy: 0 for no disease symptom, 1 for <10% infected leaf area, 2 for 10–25% infected leaf area, 3 for 25–50% infected leaf area, 4 for 50–75% infected leaf area, and 5 for >75% infected leaf area.…”

Role of QTL mapping to circumscribe various diseases in different crops with special emphasis on cotton.

“…During past couple of decades, QTL mapping technique has been improved enormously and as a result thousands of QTLs are now available for major as well as minor crops [49]. There are many reviews already available describing in detail the application of QTL mapping in various crops [6,14,26,[50][51][52][53][54][55] but, this area is not well covered for disease resistance in G. hirsutum. In this review, we will highlight the applications of QTL mapping for resistance against major disease of cotton.…”