Candidate genes related to first pod height (FPH) traits in faba bean plants are crucial for mechanised breeding. However, reports on quantitative trait locus (QTL) mapping related to the FPH of faba bean are few, thus limiting the high-quality development of the faba bean industry to a certain extent. The identification and screening of candidate genes related to FPH is extremely urgent for the advancement of mechanised breeding for faba bean. In this study, a high-density genetic linkage map was constructed using genotyping-by-sequencing (GBS) of an F3 population and QTLs (genes) related to FPH were identified. The genetic linkage map contained seven linkage groups with 3012 SNP markers with an overall length of 4089.13 centimorgan (cM) and an average marker density of 1.36 cM. Thirty-eight QTLs for the first pod node (FPN) and FPH were identified (19 each for FPN and FPH). The 19 QTLs associated with FPN were located on chromosomes 1L, 1S, 2, 3, 4, 5, and 6; the 19 QTLs associated with FPH were located on chromosomes 1L, 1S, 2, 3, 5, and 6. There was a co-localisation interval of qFPN6-1 and qFPH6-1 on chromosome 6. By annotating the QTL qFPH6-1 interval, 36 genes that may be related to FPH were identified, these genes are related to plant growth and development. The results provide a basis for the precise location of QTLs related to FPH and could accelerate the breeding of faba bean varieties adapted to mechanised harvesting.
Potato common scab is a widespread soil-borne disease that severely reduces tuber quality and market value. However, the diversity of common scab pathogens and the availability of resistance resources in major potato-producing regions of China remain poorly understood. In this study, potato common scab pathogens were isolated from diseased tubers collected in Heilongjiang Province, China, and identified based on morphological characteristics, 16S rRNA gene sequencing, and pathogenicity-related gene detection. Two pathogenic Streptomyces species, Streptomyces scabiei and Streptomyces stelliscabiei, were identified. Notably, S. stelliscabiei was identified in potato common scab samples collected in Heilongjiang Province for the first time, suggesting that it may represent an emerging causal agent of potato common scab in China. Molecular analysis revealed two pathogenicity-related gene profiles among the isolates—namely, txtAB+/tomA+/nec1+ and txtAB−/tomA+/nec1+—indicating diversity in virulence-associated gene composition. Resistance to potato common scab caused by S. stelliscabiei was further evaluated in 132 potato germplasm accessions, including domestic and introduced materials, local landraces, and widely cultivated cultivars. Significant variation in resistance levels was observed. Only two accessions were classified as highly resistant, six as resistant, and eighteen as moderately resistant, whereas the majority of accessions were susceptible or highly susceptible. Overall, this study provides the first evidence of S. stelliscabiei causing potato common scab in China, reveals pathogenicity-related gene diversity among common scab pathogens, and identifies valuable resistance resources for potato breeding. These findings contribute to a better understanding of potato common scab epidemiology and support the development of resistant cultivars.