Location: Fruit and Tree Nut Research
Title: Fruit quality in citrus: genetics and breeding for flavor and aromaAuthor
WEI, XU - University Of Florida | |
GMITTER JR., FREDERICK - University Of Florida | |
YU, YUAN - University Of Florida | |
YU, OIBIN - University Of Florida | |
Chen, Chunxian | |
Bai, Jinhe | |
Baldwin, Elizabeth - Liz | |
Plotto, Anne |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 12/16/2018 Publication Date: N/A Citation: N/A Interpretive Summary: Abstract only Technical Abstract: The unique flavor of a citrus fruit is the sum of a complex interaction among sugars, acids, and a large set of volatile compounds. Citrus flavor improvement via conventional breeding is very challenging largely due to the biochemical and genetic complexity of the traits. The volatiles, being generated from a diverse set of lipid, amino acid, and carotenoid precursors, present a major challenge for flavor improvement; but knowledge of relevant genes for production of these volatiles, and linkages with applicable markers for expeditious marker-assisted selection (MAS), is very limited. Here we report on identification of quantitative trait loci (QTLs) that affect the aroma volatiles within a hybrid family, comparisons of volatile compositions among 13 diverse citrus germplasm accessions, and the relationship between juice carotenoids and volatile contents of Valencia (VAL) and its deeply colored mutant Rohde Red Valencia (RRV) orange. A total of 206 QTLs were identified for 94 volatile compounds including 17 aroma active compounds in two mandarin parents and 116 of their F1 progeny. Some fruit aroma QTLs were identified and Candidate genes in the terpenoid biosynthetic pathway were found within the some of the identified QTL intervals. Large differences with respect to volatile compositions among the diverse citrus accessions were found, and it was possible to distinguish natural groups based on the analysis of aroma volatile levels. Finally, significant variation of carotenoids and volatile composition between VAL and RRV was observed, and correlation analysis showed that norisoprenoids degraded from ß-cryptoxanthin were significantly higher in the mutant. In summary, these carotenoid and volatile profiles, aroma QTLs, and candidate genes could lead to an efficient and feasible marker-assisted selection program for improving fruit quality through citrus breeding. |