title: Identification of bioconversion quantitative trait loci in the interspecific cross Sorghum bicolor × Sorghum propinquum.
abstract: For lignocellulosic bioenergy to be economically viable, genetic improvements must be made in feedstock quality including both biomass total yield and conversion efficiency. Toward this goal, multiple studies have considered candidate genes and discovered quantitative trait loci (QTL) associated with total biomass accumulation and/or grain production in bioenergy grass species including maize and sorghum. However, very little research has been focused on genes associated with increased biomass conversion efficiency. In this study, Trichoderma viride fungal cellulase hydrolysis activity was measured for lignocellulosic biomass (leaf and stem tissue) obtained from individuals in a F5 recombinant inbred Sorghum bicolor × Sorghum propinquum mapping population. A total of 49 QTLs (20 leaf, 29 stem) were associated with enzymatic conversion efficiency. Interestingly, six high-density QTL regions were identified in which four or more QTLs overlapped. In addition to enzymatic conversion efficiency QTLs, two QTLs were identified for biomass crystallinity index, a trait which has been shown to be inversely correlated with conversion efficiency in bioenergy grasses. The identification of these QTLs provides an important step toward identifying specific genes relevant to increasing conversion efficiency of bioenergy feedstocks. DNA markers linked to these QTLs could be useful in marker-assisted breeding programs aimed at increasing overall bioenergy yields concomitant with selection of high total biomass genotypes.
authors.affiliation: Department of Genetics and Biochemistry, Clemson University, 105 Collings Street, Clemson, SC 29634, USA.
authors.forename: Joshua P
authors.initials: JP
authors.lastname: Vandenbrink
authors.forename: Valorie
authors.initials: V
authors.lastname: Goff
authors.forename: Huizhe
authors.initials: H
authors.lastname: Jin
authors.forename: Wenqian
authors.initials: W
authors.lastname: Kong
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Paterson
authors.forename: F Alex
authors.initials: FA
authors.lastname: Feltus
mesh_terms: D018533:Biomass; D001947:Breeding; D002241:Carbohydrates / Q000737:chemistry; D002874:Chromosome Mapping / Q000379:methods; D003433:Crosses, Genetic; D017343:Genes, Plant; D008040:Genetic Linkage; D005819:Genetic Markers; D005838:Genotype; D010641:Phenotype; D040641:Quantitative Trait Loci; D045868:Sorghum / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D014961:X-Ray Diffraction; D003313:Zea mays / Q000235:genetics
chemical_list: D002241:Carbohydrates; D005819:Genetic Markers