Huanglongbing modifies quality components and flavonoid content of 'Valencia' oranges.

BACKGROUND: In order to evaluate the effect of citrus greening disease, or Huanglongbing (HLB), on quality components and flavonoid contents of 'Valencia' oranges, fruit from non-infected trees (control), from infected trees but symptom-less (asymptomatic) and from infected trees and showing clear HLB symptoms (symptomatic) were harvested in March and in May, 2013. Fruit peel, pulp and juice were separated, the main quality components were determined, and hesperidin, nobiletin, tangeretin, narirutin and didymin were quantified using liquid chromatography. RESULTS: Peel colour, total soluble solids and citric acid were similar in control and asymptomatic fruits. Symptomatic fruits were small…

METABOLIC PROMOTERS AFFECT YIELD AND FRUIT QUALITY OF 'SANFILIPPARA' AND 'TRABIA' LOQUAT

Preliminary field trials with foliar applications of phenylalanine, methionine, oxylipins and sugars have shown improvements of external color, sugar content and uniformity of maturation in grapes, pome fruits, tomatoes and melons. In this study, we hypothesized that similar improvements could be obtained both in fruit of ‘Trabia’ and ‘Sanfilippara’ loquat (Eriobotrya japonica Lindl.) with applications of a commercial formulate called Sunred (Biolchim, Bologna, Italy) and containing various concentrations of the above metabolic promoters. The study was conducted on 12 ‘Sanfilippara’ and 12 ‘Trabia’ adult loquat trees grown in an orchard near Palermo, Italy. Half of the trees…

Relazione tra potenziale idrico e contenuto idrico relativo in alberi adulti di arancio 'Valencia'

Effect of soil permanent grass cover on growth, yield and water status of rainfed olive trees in Sicily

The study was carried out in an olive grove located along the hills of northern Sicily where soil had been managed for decades by chemical weeding. Starting in 2008, one portion of the grove was left non-weeded, and the permanent grass cover was managed by mowing 2-3 times per year in winter and spring. In 2011, 2012 and 2013, yield, average drupe weight, percentage of drupe black color (veraison), trunk circumference, shoot elongation, and leaf relative water content (RWC) were determined on 34 adult trees of the cultivar 'Biancolilla' with uniform size and age. In 2013, soil organic matter content and leaf nutrient concentrations were also determined in the two portions of the grove. As e…

Regular consumption of fresh orange juice increases human skin carotenoid content

Dermal carotenoids are a good indicator of antioxidant status in the body. This study aimed to determine whether regular consumption of orange juice could increase dermal carotenoids. Two types of orange juice, obtained from regularly (CI) and partially (PRD) irrigated trees, were tested to reveal any possible association between juice and dermal carotenoids. Soluble solids, titratable acidity, and total carotenoids were quantified in the juice; skin carotenoid score (SCS) was assessed by Raman spectroscopy. Carotenoid content was 7.3% higher in PRD than in CI juice, inducing no difference in SCS. In a first trial with daily juice intakes for 25 days, SCS increased linearly (10%) in the ind…

GROWTH AND BIOMASS PARTITIONING OF YOUNG LOQUAT PLANTS UNDER WATER DEFICIT

Water scarcity in the Mediterranean areas is very common and understanding responses to drought is important for loquat management and production. The objective of this study was to evaluate the effect of water deficit on growth and biomass partitioning of loquat. Ninety 1-year-old plants of 'Marchetto' loquat (Eriobotrya japonica Lindl.) grafted on quince were grown in the greenhouse in 12-liter pots and three water regimes were imposed starting on 11 May and until 27 July, 2013. One-third of the plants was irrigated to reintegrate 100% of the water consumed (CTR); a second group of plants was irrigated with 66% of the water consumed by CTR plants (MD); a third group was irrigated with 33%…

Effect of metabolic promoters on yeld and fruit quality of 'Sanfilippara' and 'Trabia' loquat.

The Pattern of Rare Earth Elements Like a Possible Helpful Tool in Traceability and Geographical Characterization of the Soil-Olive System (Olea europaea L.)

The identification of a product, with its geographical origin, is a guaranty of the value of the foodstuff and protection from potential fraud. Extra virgin olive oil is produced or marketed as a single variety or a blend of two or more cultivars, often of different geographic origins. Therefore, to study a possible link between the soil and olive oil, we accounted crucial to analyse the behaviour of olive of different cultivars. We studied Rare Earth Elements (REE) amounts and their relationship to trace their distribution from soil to the olive pulp (Olea europea L.). The results obtained pointed out that the different cultivars of Olea did not drive significant differences in reciprocal …

Fruiting, Morphology, and Architecture of ‘Arbequina’ and ‘Calatina’ Olive Branches

Two different olive cultivars grown under a high-density hedgerow system were studied to compare their fruiting and branch architecture features and to determine the possibility to use ‘Calatina’ olive trees for intensive plantings, as a local alternative to the international reference ‘Arbequina’. Weights of two-year-old branches, fruits and leaves were recorded to estimate the growth partitioning. Growth and architectural parameters, such as shoot length, vector and diameter, branching angle, branch total length, height, width, area, and branching frequency, were determined by digital image analysis. Digital images of the fruits were also used to estimate fruit maturation by peel color an…

Huanglongbing modifies quality components and flavonoid content of ‘Valencia’ oranges

BACKGROUND: In order to evaluate the effect of citrus greening disease, or Huanglongbing (HLB), on quality components and flavonoid contents of ‘Valencia’ oranges, fruit from non-infected trees (control), from infected trees but symptom-less (asymptomatic) and from infected trees and showing clear HLB symptoms (symptomatic) were harvested in March and in May, 2013. Fruit peel, pulp and juice were separated, the main quality components were determined, and hesperidin, nobiletin, tangeretin, narirutin and didymin were quantified using liquid chromatography. RESULTS: Peel colour, total soluble solids and citric acid were similar in control and asymptomatic fruits. Symptomatic fruits were small…

Physiological and Structural Responses to Prolonged Water Deficit in Young Trees of Two Olive Cultivars

This study aimed to characterize the physiological and structural responses of potted one-year-old olive trees belonging to two olive cultivars—‘Nocellara del Belice’ and ‘Cerasuola’—exposed to prolonged drought under greenhouse conditions. Two irrigation treatments based on evapotranspiration (ET) were imposed for 69 days, i.e., well-watered (WW, 100% ET) and drought-stressed (DS, 10–30% ET). Leaf stomatal conductance (gs), stem water potential (Ψstem), transpiration (E), photosynthetic capacity (Amax), water use efficiency (WUE), stem (Kstem) and root (Kroot) hydraulic conductance, trunk diameter variations (TDV), and leaf patch attenuated pre…

Tree-to-tree variation in plant-based measurements as indicators of orange water status

A study was conducted in order to determine the sensitivity of measured indicators of the plant water status in a citrus orchard. In ten adult orange (Citrus sinensis) trees, grafted on sour orange (C. aurantium) rootstocks and drip irrigated every second day, sap flow by Granier TDP probes, leaf and xylem water potential, gas exchange and leaf and canopy thermal imaging were hourly monitored all over the day. The evaluations were performed during two separate clear-sky days with different environmental conditions, respectively in the summer and autumn seasons. Variations of environmental components (reference evapotranspiration, solar radiation, vapour pressure deficit and temperature) wer…

Effect of Sunred metabolic promoter and deficit irrigation on fruit quality of 'Valencia' oranges

This study evaluated the effect of deficit irrigation and Sunred foliar metabolic promoter on fruit quality of adult 'Valencia' orange trees. Three irrigation strategies were imposed in spring 2011: Irrigation with volumes corresponding to 100% of crop evapotranspiration applied to entire root-zone (CI), partial root-zone drying (PRD) with 50% of CI water applied to one alternated side of the root-zone, and continuous deficit irrigation (DI) with 50% of CI water applied to both sides of the root-zone. Four trees in each irrigation treatment were sprayed 30 and 20 days before harvest with Sunred metabolic promoter containing phenylalanine, methionine, mono-saccharides and oxylipins from plan…

Quantitative evaluation of the phenolic profile in fruits of six avocado (Persea americana) cultivars by ultra-high-performance liquid chromatography-heated electrospray-mass spectrometry

The phenolic profiles of six varieties of avocado (Persea americana) grown in Sicily were investigated. The ultra-high-performance liquid chromatography-heated electrospray-mass spectrometry method was developed to determine qualitative and quantitative changes in fruits at two different ripening stage. Nineteen individual phenolic compounds were detected in avocado pulp extracts. Gallic acid, sinapinic acid, vanillin, p-coumaric acid, and gentisic acid were present only in ripe fruits. On the contrary, epicatechin decreased with fruit ripening, whereas protocatechuic acid, 4-hydroxybenzoic acid, chlorogenic acid, and benzoic acid were relatively stable or exhibited erratic changes with fru…

Low Tree Vigor, Free Palmette Training Form, and High Planting Density Increase Olive and Oil Yield Efficiency in Dry, Sloping Areas of Mediterranean Regions

Exploiting biodiversity must be considered today an effective strategy to improve the sustainability of olive production systems. The evaluation of local cultivars, based on their vegetative and fruiting traits, along with an analysis of product quality, may contribute significantly to the development and diffusion of new olive-growing systems. The aim of this study was to evaluate growth, productivity, and olive oil quality of three Sicilian cultivars with different vigor/growth habit grown in four different combinations of training form and planting density. ‘Abunara’, ‘Calatina’, and ‘Nocellara del Belice’ olive trees were planted in four different int…

INFLUENCE OF BIOTIC AND ABIOTIC FACTORS ON QUALITY AND SECONDARY METABOLITES OF ‘VALENCIA’ ORANGE FRUITS

Foliar Applications with SUNRED® Biostimulant Advance and Uniform Fruit Ripening in Orange and Olive

This study evaluated the effect of foliar biostimulants on fruit quality of adult 'Valencia' orange and 'Biancolilla' olive trees. Half of the selected orange and olive trees were sprayed twice before harvest with the SUNRED® commercial mix containing phenylalanine, methionine, mono-saccharides and oxylipins from plant extracts as well as potassium salts and urea. Orange and olive yields and fruit quality were measured at harvest, and fruit peel color was determined by digital image analysis. Phenolic and sensory profiles were also determined in the olive oil. In orange, the foliar spray increased TSS:acid ratio and peel color uniformity, while in olive, it increased peel color uniformity, …