Mapping and characterization of novel parthenocarpy QTLs in tomato.
Parthenocarpy is the development of the fruit in absence of pollination and/or fertilization. In tomato, parthenocarpy is considered as an attractive trait to solve the problems of fruit setting under unfavorable conditions. We studied the genetics of parthenocarpy in two different lines, IL5-1 and IVT-line 1, both carrying Solanum habrochaites chromosome segments. Parthenocarpy in IL5-1 is under the control of two QTLs, one on chromosome 4 (pat4.1) and one on chromosome 5 (pat5.1). IVT-line 1 also contains two parthenocarpy QTLs, one on chromosome 4 (pat4.2) and one on chromosome 9 (pat9.1). In addition, we identified one stigma exsertion locus in IL5-1, located on the long arm of chromosome 5 (se5.1). It is likely that pat4.1, from IL5-1 and pat4.2, from IVT-line 1, both located near the centromere of chromosome 4 are allelic. By making use of the microsynteny between tomato and Arabidopsis in this genetic region, we identified ARF8 as a potential candidate gene for these two QTLs. ARF8 is known to act as an inhibitor for further carpel development in Arabidopsis, in absence of pollination/fertilization. Expression of an aberrant form of the Arabidopsis ARF8 gene, in tomato, has been found to cause parthenocarpy. This candidate gene approach may lead to the first isolation of a parthenocarpy gene in tomato and will allow further use in several crop species.
Gorguet
Benoit
B
Graduate School of Experimental Plant Sciences, Wageningen UR Plant Breeding, 6700AJ, Wageningen, The Netherlands. benoit.gorguet@wur.nl
Eggink
Pieter Martijn
PM
Ocaña
Juan
J
Tiwari
Aparna
A
Schipper
Danny
D
Finkers
Richard
R
Visser
Richard G F
RG
van Heusden
Adriaan W
AW
D017360:Arabidopsis / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D032461:Chromosomes, Plant; D018744:DNA, Plant / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000254:growth & development*; D005638:Fruit / Q000235:genetics / Q000254:growth & development*; D018551:Solanum lycopersicum / Q000502:physiology*; D010312:Parthenogenesis / Q000502:physiology*; D010641:Phenotype; D030821:Plants, Genetically Modified / Q000235:genetics*; D040641:Quantitative Trait Loci
D029681:Arabidopsis Proteins; D018744:DNA, Plant; D004268:DNA-Binding Proteins; C495666:auxin response factor 8, Arabidopsis