title: A QTL that confers resistance to Colorado potato beetle (Leptinotarsa decemlineata [Say]) in tetraploid potato populations segregating for leptine.
abstract: Genetic resistance to Colorado potato beetle (Leptinotarsa decemlineata [Say]) from Solanum chacoense has been incorporated in the tetraploid potato selection, ND4382-19, which is highly resistant and contains moderate level of foliar leptines. We recently reported using ND4382-19 progeny, population ND5873 (ND4382-19 x Chipeta), to map two genes that segregated as complementary epistatic genes that allow accumulation of leptinidine (Lep) and acetyl-leptinidine (AL) on chromosomes 2 and 8, respectively. We describe here the characterization of a second half-sib population NDG116 (ND4382-19 x N142-72). In this population, solasodine from parent N142-72, which has Solanum berthaultii in its background, was predominant over solanidine-based alkaloids. Concentrations of solanidine, leptinidine, and acetyl-leptinidine were 15-, 5-, and 14-fold lower than in the ND5873 population. Nevertheless, Lep and AL mapped to the same locations on chromosomes 2 and 8 of parent ND4382-19, respectively. The two populations were evaluated for resistance to Leptinotarsa in field assays, and by detached leaf assay for population NDG116. In both families, QTL analysis identified a major QTL from ND4382-19 on the distal end of chromosome 2, close to the Lep locus. The contribution of this QTL to resistance ranged from 11 to 34% for ND5873 at four field sites. Contribution to resistance from the linkage group that contains the gene AL for the accumulation of leptine was not detected. In family NDG116, the same chromosome 2 QTL was detected for field and detached leaf assays, explaining 26 and 12% of the variance for defoliation and larval development, respectively. These data may indicate another resistance mechanism besides leptine in the Leptinotarsa resistance observed in these populations.
authors.affiliation: Instituto de Investigaciones Agropecuarias (INIA), CRI-Rayentué, Casilla 13, Rengo, Chile. bsagredo@inia.cl
authors.forename: Boris
authors.initials: B
authors.lastname: Sagredo
authors.forename: N
authors.initials: N
authors.lastname: Balbyshev
authors.forename: A
authors.initials: A
authors.lastname: Lafta
authors.forename: H
authors.initials: H
authors.lastname: Casper
authors.forename: J
authors.initials: J
authors.lastname: Lorenzen
mesh_terms: D000818:Animals; D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D001517:Coleoptera / Q000254:growth & development*; D003120:Colorado; D017343:Genes, Plant; D007300:Insect Control; D011123:Polyploidy; D040641:Quantitative Trait Loci; D012991:Solanaceous Alkaloids / Q000235:genetics*; D032322:Solanum / Q000235:genetics*
chemical_list: D012991:Solanaceous Alkaloids
references.citation: Nucleic Acids Res. 1995 Nov 11;23(21):4407-14
references.pmid: 7501463
references.citation: J Agric Food Chem. 2006 Nov 15;54(23):8655-81
references.pmid: 17090106
references.citation: J Hered. 2003 Jul-Aug;94(4):358-9
references.pmid: 12920109
references.citation: Theor Appl Genet. 2006 Dec;114(1):131-42
references.pmid: 17082950
references.citation: Theor Appl Genet. 1994 Mar;87(8):973-87
references.pmid: 24190532
references.citation: Heredity (Edinb). 1992 Oct;69(4):315-24
references.pmid: 16718932
references.citation: Genetics. 2001 Mar;157(3):1369-85
references.pmid: 11238421
references.citation: Theor Appl Genet. 2002 Nov;105(6-7):1010-1018
references.pmid: 12582928
references.citation: Mamm Genome. 2001 Dec;12(12):930-2
references.pmid: 11707780
references.citation: J Econ Entomol. 2001 Oct;94(5):1260-7
references.pmid: 11681692