Next Article in Journal
Characterization of Chickpea (Cicer arietinum L.) Flour Films: Effects of pH and Plasticizer Concentration
Next Article in Special Issue
Physiological and Metabolic Responses of Rice to Reduced Soil Moisture: Relationship of Water Stress Tolerance and Grain Production
Previous Article in Journal
Ginsenoside Rh2 Ameliorates Doxorubicin-Induced Senescence Bystander Effect in Breast Carcinoma Cell MDA-MB-231 and Normal Epithelial Cell MCF-10A
Previous Article in Special Issue
On a Cold Night: Transcriptomics of Grapevine Flower Unveils Signal Transduction and Impacted Metabolism
Open AccessArticle

Developmental Stage- and Genotype-Dependent Regulation of Specialized Metabolite Accumulation in Fruit Tissues of Different Citrus Varieties

Faculty of Agriculture, Tabriz University of Tabriz, Tabriz 5166616471, Iran
Citrus and Subtropical Fruits Research Center, Ramsar 4691733113, Iran
Department de Ciències Agràries i del Medi Natural, Universitat Jaume I, 12071 Castelló de la Plana, Spain
Author to whom correspondence should be addressed.
Int. J. Mol. Sci. 2019, 20(5), 1245;
Received: 1 February 2019 / Revised: 7 March 2019 / Accepted: 7 March 2019 / Published: 12 March 2019
(This article belongs to the Special Issue Plant Metabolism in Crops: A Systems Biology Perspective)
Flavor traits in citrus are the result of a blend of low molecular weight metabolites including sugars, acids, flavonoids and limonoids, these latter being mainly responsible for the characteristic bitter flavor in citrus. In this work, the genotype- and developmental stage-dependent accumulation of flavonoids and limonoids is addressed. To fulfill this goal, three models for citrus bitterness: bitter Duncan grapefruit, bittersweet Thomson orange and sweet Wase mandarin were selected from a total of eight different varieties. Compounds were annotated from LC/ESI-QqTOF-MS non-targeted metabolite profiles from albedo and pulp tissues. Results indicated that the specific blend of compounds providing the characteristic flavor trait is genotype-specific and hence under genetic control, but it is also regulated at the developmental level. Metabolite profiles in albedo mirrored those found in pulp, the edible part of the fruit, despite differences in the concentration and accumulation/depletion rates being found. This is particularly relevant for polymethoxylated flavones and glycosylated limonoids that showed a clear partitioning towards albedo and pulp tissues, respectively. Fruit ripening was characterized by a reduction in flavonoids and the accumulation of limonoid glycosides. However, bitter grapefruit showed higher levels of limonin A-ring lactone and naringin in contrast to sweeter orange and mandarin. Data indicated that the accumulation profile was compound class-specific and conserved among the studied varieties despite differing in the respective accumulation and/or depletion rate, leading to different specialized metabolite concentration at the full ripe stage, consistent with the flavor trait output. View Full-Text
Keywords: bitterness; citrus genotypes; flavonoids; harvesting time; limonoids; metabolomics bitterness; citrus genotypes; flavonoids; harvesting time; limonoids; metabolomics
Show Figures

Graphical abstract

MDPI and ACS Style

Nadi, R.; Golein, B.; Gómez-Cadenas, A.; Arbona, V. Developmental Stage- and Genotype-Dependent Regulation of Specialized Metabolite Accumulation in Fruit Tissues of Different Citrus Varieties. Int. J. Mol. Sci. 2019, 20, 1245.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

Back to TopTop