Identification of three new resources of resistance to Fusarium head blight in wheat

Abstract

Fusarium head blight (FHB) mainly caused by Fusarium species is one of the most important diseases threatening worldwide wheat production. To develop new FHB resistance resources, disease resistances of three new wheat lines L958, L962 and L987 were evaluated over a period of several years. We employed L699 (PI672540) and L661 as the resistant and susceptible control, respectively. Moderate FHB resistance was observed in these three wheat lines, among which the genotype L958 was found a good resource for yield, quality and FHB resistance improvement. In addition, genotype L962 was found to be resistant to powdery mildew, and both L958 and L987 carried the YrL693 gene conferring stripe rust resistance. The study provides promising results for accelerating the resistance breeding of the three wheat lines. Keywords: agronomic trait; FHB; resistance evaluation; Triticum aestivumFusarium head blight (FHB), mainly caused by Fusarium graminearum Schwabe and F. culmorum WG Smith, is a serious wheat (Triticum aestivum L.) disease worldwide (Bai & Shaner 2004;Li et al. 2017). In China, FHB epidemics have frequently occurred in the middle to lower valleys of the Yangtze River (Yao & Lu 2000). In recent years, FHB has spread to the southwest of China, including Sichuan Province (Zhang et al. 2011;Liu et al. 2015;Yang et al. 2016), where the climate was warm and rainy. Furthermore, FHB is also a fungal disease threatening food and economic security due to its contamination with mycotoxins, decreasing the wheat yield and quality (Zwart et al. 2008). At present, there is still no economic and effective way to control this disease. Developing resistant cultivars is an important approach to control this disease, for which the decisive step is to identify new germplasm with multi-resistance.Some effective FHB resistance sources have been identified in common wheat (Chu et al. 2011), and some FHB resistance quantitative trait loci (QTLs) have also been found and mapped in wheat relatives (Cai et al. 2005;Chen et al. 2007). In recent years, some geneticists and breeders have paid much ata These authors contributed equally to this work. 16 Original PaperCzech Journal of Genetics and Plant Breeding, 55, 2019 (1) (Luo et al. 2009;Liu et al. 2013). In addition, four new FHB resistant wheat germplasms were identified and released , which demonstrated the possibility of using Th. intermedium to develop novel wheat germplasm with different disease resistance. However, some breeding problems still remain and new materials with effective resistance to various diseases need to be developed.The research in this paper is aimed at screening wheat FHB resistance germplasm derived from an MY11 × YU25 cross for FHB resistance improvement. MATERIAL AND METHODSPlant material. The three wheat lines L958, L962, and L987 were selected from the F 7 populations derived from an MY11 × YU25 cross during 2007. MY11 is a wheat cultivar widely grown in southwestern China, while YU25 is a wheat cultivar with a foreign pedigree of Th. intermedium .FH...