Linkage map development and localization of QTLs related to yield in Pea (Pisum sativum L.)

GUINDÓN, MARÍA FERNANDA; MARTIN, EUGENIA; CRAVERO, VANINA; COINTRY, ENRIQUE

Foz de Iguazu

Congreso; 11th International Congress of Plant Molecular Biology; 2015

Pea breeding programs aim to develop high yielding cultivars with desirable agronomic and quality attributes. Yield is a complex trait that presents a quantitative inheritance, and the regions of the genome associated with it are called Quantitative Traits Loci (QTLs). Linkage maps based on different molecular markers are a powerful tool to identify those QTLs. The aims of this work were to develop a new linkage map and to identify and localize QTLs related to yield in pea. A total of 50 SRAP combinations and 35 SSR were evaluated in 112 F2 individuals derived from a cross between DDR14 and Explorer lines. The linkage map constructed consists in 281 genetic markers distributed into 7 linkage groups covering a total of 763.076 cM, with an average distance between adjacent markers of 2.72 cM. This map was used to identify and localize QTLs associated to pod number, pod length and pod diameter using the composite interval mapping (CIM) approach. All the traits showed continuous variation with normal frequency distributions. The CIM analysis revealed a total of 8 QTLs (LODmin=3) distributed along three chromosomes. Pod number was determined by three QTLs that explained from 16.5 to 35.9 % of the phenotypic variation. Four QTLs influence pod length (14.7 to 24.0 % of the variation) and one QTL is related to pod diameter (17.1 % of the variance). This work provides preliminary information on the genetic control of the yield-related traits and identifies regions of the pea genome interesting for use in breeding programs.