Mapping of quantitative trait loci conferring resistance to bacterial wilt in tobacco (Nicotiana tabacum L.)

Abstract

Tobacco bacterial wilt (TBW) is one of the most serious tobacco diseases in the world. Studies have shown that tobacco resistance to TBW is quantitatively inherited. This study aimed to map quantitative trait loci (QTL) conferring TBW resistance. An F 2 : 3 population containing 237 lines was developed from a cross between two flue-cured tobacco cultivars, 'Yanyan 97' (YY97; moderately resistant to TBW) and 'Honghua Dajinyuan' (HD; highly susceptible to TBW), and a linkage map consisting of 201 simple sequence repeats (SSR) markers and spanning a total length of 2326.7 cM was constructed based on the population. Field experiments were conducted 2011 and 2012, and disease symptoms were investigated three times in each year. The phenotypic data were analysed either separately or jointly for QTL mapping using the software QTLNetwork 2.1. Eight QTL with significant main effects were mapped on chromosomes 2, 6, 12, 17 and 24. A major QTL (qBWR17a) was detected on chromosome 17, which explained up to 30% of the phenotypic variation. The results can facilitate marker-assisted selection (MAS) in TBW resistance breeding programme.

Identification of Novel Quantitative Trait Nucleotides and Candidate Genes for Bacterial Wilt Resistance in Tobacco (Nicotiana tabacum L.) Using Genotyping-by-Sequencing and Multi-Locus Genome-Wide Association Studies

“…The broad-sense heritability for TBW-DI was moderate (61-81%) and differed between environments (Table 1). These observations are similar to other studies in tobacco (Nishi et al, 2003;Qian et al, 2013;Lan et al, 2014), including some heritability problems (Gao et al, 2010). Genetic diversity in modern tobacco cultivars is low (Wernsman, 1999;Leng et al, 2010); only a few genotypes are ancestors of most cultivars.…”

“…Tobacco ( Nicotiana tabacum L.; 2n = 48) is an important cash crop in many countries, including China, and a valuable model system in genetic engineering and molecular biology. Tobacco bacterial wilt (TBW) caused by Ralstonia solanacearum is a destructive soil-borne disease in many regions worldwide ( Nishi et al, 2003 ; Lan et al, 2014 ; Drake-Stowe et al, 2017 ). Infected tobacco plants typically exhibit symptoms such as leaf wilt, root and stem necrosis, and growth retardation, followed by plant death, which reduce yield and quality ( Qian et al, 2013 ).…”

“…In China, the disease occurrence has been steadily rising, reaching 15–30% in some areas ( Jiang et al, 2017 ), posing a serious threat to tobacco production in the four main tobacco-growing regions, including 14 provinces ( Li et al, 2016 ). Several methods, including crop rotation and soil fumigation, can reduce some economic losses from the disease; however, none provide sufficient protection ( Nishi et al, 2003 ; Lan et al, 2014 ).…”

QTL analysis of resistance to bacterial wilt caused by <i>Ralstonia solanacearum</i> in potato

“…The genetic resistance to bacterial wilt has been reported in various cultivated potato species (including S. tuberosum and S. phureja) and the closely related wild species (including S. chacoense) (Chen et al 2013, Fock et al 2000, Katayama and Kimura 1987, Jaworski et al 1980, Sequeira and Rowe 1969, Siri et al 2009, Thurston and Lozano 1968. Quantitative trait locus (QTL) analyses of bacterial wilt resistance in Solanaceae crops were conducted in tomato (Carmeille et al 2006, Wang et al 2000, eggplant (Lebeau et al 2013), and tobacco (Lan et al 2014, Qian et al 2013. In potato, 109 Solanum chacoense-specific simple sequence repeat alleles in 44 somatic hybrids between S. chacoense and S. tuberosum were surveyed, in which three alleles on chromosomes 2 and 9 were significantly associated with the resistance to R. solanacearum (race 1, biovar 3) (Chen et al 2013).…”

Characterization and Mapping of a Novel Premature Leaf Senescence Mutant in Common Tobacco (Nicotiana tabacum L.)

“…Tong et al [32] developed a total of 4886 SSR markers (including 1365 genomic SSRs and 3521 EST-SSRs), which were functional in a set of eight tobacco varieties of four different types and were essentially non-overlapping with the set published by Bindler et al [30,31]. These SSR markers have been wildly used for the identification of quantitative trait loci (QTLs) associated with tobacco disease resistance [33,34,35,36] and tobacco traits [37], and they have also been used for genetic diversity analysis of tobacco varieties [38,39].…”