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Jatropha curcas (known as jatropha and physic nut) can be used as an alternative source for biodiesel and biomass production. However, conventional breeding of J. curcas needs time, labor and land for characterization and evaluation of the progenies owing to its perennial growth habit. Quantitative trait loci (QTL) mapping can help identifying marker-trait association and accelerate breeding process of perennial crops through marker-assisted selection. However, the genetic basis for woody biomass improvement in jatropha has not yet been studied. In this manuscript, we report the construction of a SNP-based linkage map and detection of QTLs for woody-biomass-related traits using an F2 population of the interspecific cross between J. curcas and Jatrophaintegerrima. A high-density genetic linkage map containing 2,179 SNPs was constructed. As high as 89.26% of the SNP markers developed from these interspecific progenies expressed significant segregation distortion. Most of the distorted markers showed neither gametophytic nor zygotic selection, except those on linkage groups 3, 5 and 6 which showed gametophytic and zygotic selection. The F2 population showed high variation and transgressive segregation for plant height, canopy width and wood density. QTL analyses detected 5, 8, and 7 loci for plant height, canopy width, and wood density, respectively. The SNPs linked to these QTLs could be incorporated into marker-assisted breeding to maximize the selection gain in jatropha biomass breeding. [ABSTRACT FROM AUTHOR]

Cercospora leaf spot (CLS) disease and bruchids are the common disease and insect pest causing yield loss in mung bean (Vigna radiata (L.) R. Wilczek). ‘KUML4’ is an improved mung bean cultivar grown in Thailand having high yield, early and highly synchronous maturity, large seed size, but susceptible to CLS disease and bruchids. This study was conducted to improve ‘KUML4’ through introgression of VrTAF5 for CLS resistance and VrPGIP2 for bruchid (Callosobruchus maculatus) resistance from landrace mung bean accessions ‘V4718’ and ‘V2808’, respectively, by marker-assisted backcrossing (MABC). In the MABC, foreground selections were performed using VrTAF5- and VrPGIP2-specific markers. The BC3F3 pyramided lines with KUML4 background carrying both VrTAF5 and VrPGIP2 genes were developed and evaluated for agronomic and yield-related traits, CLS resistance, and bruchid resistance. Three BC3F3 lines, KUML4-2020-21, KUML4-2020-23, and KUML4-2020-60, exhibiting superior agronomic and yield-related traits, CLS resistance, and bruchid resistance than ‘KUML4’ were successfully obtained via MABC. Under the CLS outbreak, these lines showed 248.5%-331.7% higher seed yield than ‘KUML4’. The lines expressed nearly perfect resistance to bruchid (< 5% seeds damaged). These lines can be developed into new resistant mung bean cultivars in the future. [ABSTRACT FROM AUTHOR]