QTL analysis for fruit yield components in table grapes (Vitis vinifera)

Abstract

A segregation population of 184 genotypes derived from a pseudo-testcross of table grapes (Vitis vinifera), together with 203 AFLP and 110 SSR markers was used to detect quantitative trait loci (QTLs) for fruit yield components. Diffferent QTLs, a low percentage of phenotypic variance explained by the QTLs detected and QTL instability over years were detected for each fruit yield component. These results confirm the complex genetic architecture of the yield components in grapevine due to the perennial nature of this species, which has to adapt to yearly variations in climate. Phenotypic correlation analyses between fruit yield components were also performed. The negative correlation between berry weight and the number of berries per cluster seems to have an indirect negative effect on cluster weight, as revealed by the path coefficient analysis; however, this negative correlation was not supported at the molecular level because no coincident QTLs were observed between these traits. Nonetheless, the possibility to select seedless genotypes with large berries without affecting cluster weight needs to be substantiated in future experiments because factors such as sample size and heritability might influence QTL identification in table grapes.

QTL detection for physicochemical characteristics of cashew apple

“…Most of the identified QTL explained less than 10% of the variation and were considered small-effect QTL. Similar results have been reported in various QTL studies on fruit quality (Fanizza et al 2005, Kenis et al 2008, Santos et al 2010.…”

Genetic dissection of agronomic traits within a segregating population of breeding table grapes

“…It is an extremely complex quantitative character both because of the number of segregating loci controlling all of the traits involved in yield and of the influence of non-genetic factors (Fanizza et al, 2005).…”

“…A multitude of investigations have been conducted on the inheritance of yield and yield components in fruit tree species using the classic biometrical approach, and, while these studies have been useful for making predictions on the genetic progress occurring in plant breeding programs, they have not provided information on individual genes (or group of genes) influencing quantitative trait loci (QTL) (Fanizza et al, 2005).…”

“…The majority of these studies have concentrated on disease resistance introgressed from native North American species (Barker et al, 2005;Riaz et al, 2008;Marguerit et al, 2009;Coleman et al, 2009). Other studies focus on developing genetic maps and identifying QTL for agronomic traits such as seedlessness, berry size, fruit ripening, fruit quality, and cluster structure (Doligez et al, 2002;Fanizza et al, 2005;Mejía et al, 2007). Costantini et al (2007) identified clusters of QTL for different berry and phenology traits associated with each other, suggesting that the involved genes are either linked or have pleiotropic relationships.…”

Quantitative trait locus analysis of leaf morphological characters, yield-related traits, and secondary metabolite contents in Eucommia ulmoides

“…The instability of QTLs over years has been reported for leaf traits in other tree species (Scalfi et al, 2004;Gailing, 2008;Gailing et al, 2013). Fanizza et al (2005) hypothesized that QTL instability over time may be due to the presence of different genes or the differential expression of these genes due to changes in genotypic sensitivity to annual variations in the climatic conditions. Plomion et al (1996) assumed that maturation in trees induces a progressive shift in the genetic control of phenotypic traits.…”