Metabolic profiling of ripe olive fruit in response to moderate water stress

Abstract

a b s t r a c tThe concentrations of different metabolites in olive (Olea europaea (L.)) fruit at harvest can be affected by water availability, with significant consequences on the composition and the quality of the resulting oil. The aim of the present study was to profile the metabolic composition of ripe olives (cv. Cipressino) grown under water-stress and irrigated conditions applied during the last part of the fruit developmental cycle (from pit hardening to commercial harvest). The imposed conditions resulted in a moderate water stress (−3.5 MPa) at the end of the experimental period. Samples (pulp + skin) of fruit collected at the stage of complete epicarp pigmentation were analyzed by means of GC-MS. In total, 176 metabolites were detected, of which 57 were identified. Principal component analysis (PCA) of stress and non-stress treatments resulted in clearly separated profiles with the first principal component (PC1) mostly correlated with the organic acid content. Of the 57 compounds identified, 19 metabolites (organic acids, fatty acids, soluble sugars, and terpens) accumulated differently in the two sets of samples. A reduction in soluble sugars and unsaturated fatty acids was detected in water stressed samples, suggesting an acceleration of the ripening process. These results highlighted the validity of metabolic profiling to study the effects of water stress in terms of both fruit composition and physiology.

Gene Regulatory Networks Elucidating Huanglongbing Disease Mechanisms

“…In addition to the previous transcriptome data from the mature fruit peel [21], RNA-Seq was performed on other three tissues from each of four HLB phenotypes (Table 1), RNA-Seq data from all four tissues were analyzed together using the new reference dataset [23]. For the 16 cDNA libraries, a total of 889 million 85 bp paired-end raw reads were obtained with the Illumina Genome Analyzer II.…”

“…Previous studies have focused on mature leaf tissues, using plants artificially infected with CaLas, or on mature fruit in orchard conditions [21]. These did not examine the link between host responses in source and sink tissues, where mature leaves comprise the source, and young leaves along with immature fruits comprise the sink.…”

“…Next-generation sequencing technologies can enable a deeper analysis of the RNA population than microarrays, including rare and unknown transcripts, offering a more precise and accurate picture of the transcriptome [15], [16]. Metabolomics has proven effective for studying metabolic changes [17] in response to agronomic treatments and environmental stresses including CaLas infection [18]–[21].…”

Profiling of primary metabolites and flavonols in leaves of two table grape varieties collected from semiarid and temperate regions

“…Moreover, the level of maltotriose in 'Shami' leaves is much higher in the S-AR, which may indicate its involvement in the plant responses to abiotic stresses. Melezitose is reported to exist in high level upon stress (Martinelli et al, 2013) and correlates well with the level of desiccation tolerance (Gechev et al, 2014).…”

Transcriptome and metabolome analysis of Citrus fruit to elucidate puffing disorder

“…Transcriptomics, the quantification of transcripts in a cell, includes the use of next-generation techniques [6][7][8][9] and microarrays [10][11][12]. Metabolomics may be a good complement to transcriptomics and proteomics [13][14][15][16]. The metabolome is more directly related to phenotype than transcripts or proteins because metabolic fluxes are governed not only by gene expression, but also by post-transcriptional and post-translational events.…”