Open AccessCold Sweetening in Diploid Potato: Mapping Quantitative Trait Loci and Candidate Genes
Author(s) -
Cristina M. Menéndez,
Enrique Ritter,
Ralf Schäfer-Pregl,
Birgit Walkemeier,
A. Kalde,
Francesco Salamini,
Christiane Gebhardt
Publication year - 2002
Publication title -
genetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.792
H-Index - 246
eISSN - 1943-2631
pISSN - 0016-6731
DOI - 10.1093/genetics/162.3.1423
Subject(s) - quantitative trait locus , biology , sucrose , genetics , fructose , candidate gene , invertase , sucrose synthase , sucrose phosphate synthase , gene , ploidy , sugar , amplified fragment length polymorphism , genetic linkage , biochemistry , population , genetic diversity , demography , sociology
A candidate gene approach has been used as a first step to identify the molecular basis of quantitative trait variation in potato. Sugar content of tubers upon cold storage was the model trait chosen because the metabolic pathways involved in starch and sugar metabolism are well known and many of the genes have been cloned. Tubers of two F(1) populations of diploid potato grown in six environments were evaluated for sugar content after cold storage. The populations were genotyped with RFLP, AFLP, and candidate gene markers. QTL analysis revealed that QTL for glucose, fructose, and sucrose content were located on all potato chromosomes. Most QTL for glucose content mapped to the same positions as QTL for fructose content. QTL explaining >10% of the variability for reducing sugars were located on linkage groups I, III, VII, VIII, IX, and XI. QTL consistent across populations and/or environments were identified. QTL were linked to genes encoding invertase, sucrose synthase 3, sucrose phosphate synthase, ADP-glucose pyrophosphorylase, sucrose transporter 1, and a putative sucrose sensor. The results suggest that allelic variants of enzymes operating in carbohydrate metabolic pathways contribute to the genetic variation in cold sweetening.