title: Genetic analysis of rhizomatousness and its relationship with vegetative branching of recombinant inbred lines of Sorghum bicolor × S. propinquum.
abstract: OBJECTIVE
  Rhizomes, subterranean stems that grow horizontally, are a storage organ that is highly associated with overwintering and regrowth. This quantitative study aimed to discover genetic determinants of rhizomatousness, an important trait related to perenniality and invasiveness.
  
  
  METHODS
  A population of 161 individuals of a recombinant inbred line (RIL) derived from morphologically distinct parents, Sorghum bicolor and Sorghum propinquum, which segregates for rhizomatousness, was phenotyped and genetically mapped.
  
  
  RESULTS
  Seven genomic regions influenced rhizomatousness in this population; four were "consensus" regions that correspond with previously detected quantitative trait loci (QTLs) in an F2 population of the same pedigree and with different levels of vegetative branching. Because rhizomatousness is a plastic trait that is greatly influenced by environment, overlap between regions discovered in the RIL and F2 populations validates the position and effect of QTLs. Correspondence with regions influencing vegetative branching indicates that some genes and biochemical pathways may influence both vegetative branching and rhizomatousness, while genes influencing only one trait may confer divergent aspects of development of these organs.
  
  
  CONCLUSIONS
  Identifying genes conferring rhizomatousness and understanding their functions may provide opportunities to regulate plant growth for diverse applications. Increasing rhizomatousness may promote the productivity and perenniality of many grasses, especially biomass-dedicated crops, while decreasing rhizomatousness may improve monocarpic grain production and offer means to control many noxious weeds.
authors.affiliation: Plant Genome Mapping Laboratory, 111 Riverbend Rd, University of Georgia, Athens, Georgia 30602 USA.
authors.forename: Wenqian
authors.initials: W
authors.lastname: Kong
authors.affiliation: Plant Genome Mapping Laboratory, 111 Riverbend Rd, University of Georgia, Athens, Georgia 30602 USA.
authors.forename: Changsoo
authors.initials: C
authors.lastname: Kim
authors.affiliation: Plant Genome Mapping Laboratory, 111 Riverbend Rd, University of Georgia, Athens, Georgia 30602 USA.
authors.forename: Valorie H
authors.initials: VH
authors.lastname: Goff
authors.affiliation: Plant Genome Mapping Laboratory, 111 Riverbend Rd, University of Georgia, Athens, Georgia 30602 USA.
authors.forename: Dong
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Plant Genome Mapping Laboratory, 111 Riverbend Rd, University of Georgia, Athens, Georgia 30602 USA.
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Paterson
mesh_terms: D002874:Chromosome Mapping; D003433:Crosses, Genetic; D018745:Genome, Plant; D000069600:Plant Breeding; D040641:Quantitative Trait Loci; D027343:Rhizome / Q000033:anatomy & histology / Q000235:genetics / Q000254:growth & development*; D045868:Sorghum / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development
keywords: Poaceae; Sorghum bicolor × S. propinquum; axillary shoots; overwintering; quantitative traits; regrowth; rhizomes