First report of olive anthracnose caused by Colletotrichum gloeosporioides in Tunisia

Ripe and overripe olive fruits (cv. Meski, Manzanilla and Picholine) showing circular spots 1 to 10 mm in diameter, slightly depressed and reddish-brown in color, were collected from local markets and orchards located in the regions of Takelsa, Zarzis and Rgueb in Tunisia. Colletotrichum gloeosporioides was isolated from symptomatic fruits and Koch’s postulates were fulfilled. This is the first report of Colletotrichum gloeosporioides causing anthracnose of olives in Tunisia

First report of olive anthracnose caused by <I>Colletotrichum gloeosporioides</I> in Tunisia

Ripe and overripe olive fruits (cv. Meski, Manzanilla and Picholine) showing circular spots 1 to 10 mm in diameter, slightly depressed and reddish-brown in color, were collected from local markets and orchards located in the regions of Takelsa, Zarzis and Rgueb in Tunisia. Colletotrichum gloeosporioides was isolated from symptomatic fruits and Koch’s postulates were fulfilled. This is the first report of Colletotrichum gloeosporioides causing anthracnose of olives in Tunisia

Effect of foliar Boron application on growth, phenology, yield and oil quality of olive trees (cv. Arbequina) conducted under a high density planting system

1 .pdf (3 Tabls.) copia del póster original presentado por los autores en el Simposio Internacional.Foliar boron fertilization is commonly used in intensive olive orchards without knowledge about the efficiency of this fertilization on olive production.Peer reviewe

The possibility of using inflorescence analysis to evaluate the nutritional status of olive trees

1 .pdf (2 Tabls.) copia del Póster original presentado por los autores. Se acompaña de 1 .pdf copia del resumen oficial.The main objective of this work was to evaluate if inflorescence analysis can be considered as an alternative to foliar diagnosis in determining the nutritional status of olive orchards. Olive leaves from cv. Arbequina, planted under high density planting system in two different sites (Tunisia and Spain), were sampled at 5 developmental stages (inflorescence emergence, fruit set, pit hardening, fruit development and fruit maturity) during two years, 2006 and 2007.This study was supported by AECI-MAE projects A/3005/05 and A/5 199/06.Peer reviewe

Assessment of tolerance to NaCl salinity of five olive cultivars, based on growth characteristics and Na+ and Cl− exclusion mechanisms

10 Pags., 2 Tabls., 6 Figs.Changes caused by NaCl-induced salinity on several growth parameters and ions accumulation have been measured in five olive (Olea europaea L.) cultivars (‘Chemlali’, ‘Chetoui’, ‘Koroneiki’, ‘Arbequina I18’, and ‘Arbosana I43’) growing in a greenhouse in nutrient solution pot experiment. One-year-old plants were transplanted to sand–perlite (1:1) culture, and were irrigated with half-strength Hoagland nutrient solution containing NaCl at various levels (0.5, 50, 100 and 200 mM). Salinity induced significant decrease in growth parameters, but to a different extent in each cultivar. Leaf growth and total leaf area per plant were significantly affected by all salinity treatments in all studied cultivars, being ‘Arbequina I18’ the most sensitive cultivar. Leaf drop phenomenon was observed from 60 days after salt application at high salinity treatments, mainly in Arbequina I18. Contrary to leaf area, leaf thickness increased progressively during the experiment. ‘Chemlali’ developed thicker leaves at the two highest salinity treatments when compared to the other cultivars. Na+ and Cl− concentrations were higher in roots than in shoots and leaves in most of the cultivars investigated. The effectiveness of Na+ exclusion mechanism in the roots differed significantly among studied cultivars, working effectively in ‘Chemlali’ (by inhibiting translocation of Na+ to the aerial part) and being much less efficient in ‘Arbequina I18’. Furthermore, leaf abscission can be considered as an additional tolerance mechanism of olive cultivars allowing the elimination of leaves that had accumulated Na+ and Cl− ions. Tolerance to salinity stress was as follows: ‘Chemlali’ > ‘Chetoui’ > ‘Arbosana I43’ > ‘Koroneiki’ > ‘Arbequina I18’. This order of salt tolerance was indicated by lower reduction in plant growth parameters (shoot elongation, trunk diameter, total plant dry weight, internodes length, and total leaf area), the increase of leaf thickness, and by the effectiveness of the exclusion mechanism of Na+ and Cl− in the root system.This work was supported by grants from Olive tree Institute to Ajmi Larbi and Monji Msallem. Fermín Morales wishes to thank Gobierno de Aragón (A03 research group) for financial support.Peer reviewe

Rapid quantitative determination of oleuropein in olive leaves (Olea europaea) using mid-infrared spectroscopy combined with chemometric analyses

International audienceOleuropein, the major active compound in olive leaf, is well known for its benefits for human health. Oleu-ropein is classically quantified by HPLC, which is time and chemical consuming, laborious and expensive. The aim of this work was to examine the potential of mid-infrared spectroscopy, as a rapid tool, to predict oleuropein content in olive leaf from five Tunisian cultivars (Chemlali, Chetoui, Meski, Sayali and Zarrazi) and one French cultivar (Bouteillan). The reference data of oleuropein content were obtained by the HPLC method. Hundred five samples were analyzed by HPLC and mid-infrared spectroscopy. Samples were randomly divided in a calibration set (73 samples) and in a validation set (32 samples). The spectral data sets were correlated with reference data of oleuropein content by using partial least squares (PLS) regression algorithm. The results showed that the PLS model gave satisfactory model for quantitative prediction of oleuropein content in olive leaf (relative error of prediction = 8.5%). The correlation coefficient was 0.91 and 0.74 for calibration set and validation set, respectively. It can be concluded that mid-infrared spectroscopy constitutes a promising technique for rapid quantification of oleuropein in olive leaf

Differences between native and introduced olive cultivars as revealed by morphology of drupes, oil composition and SSR polymorphisms: a case study in Tunisia

email: [email protected] Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699International audienceOlive cultivars are diversified but nothing is known on their origins and if they are local or introduced in any regions. The study aims to determine which traits may help to identify native from introduced cultivars and oleaster trees. We compared cultivars and oleasters from North Tunisia to determine their relationships based on morphological traits, oil composition and SSR genotyping at seven loci. We used those parameters to examine 32 cultivar trees from 17 denominations and 70 oleaster trees sampled. We used multivariate analysis, enabling to retain the best variables, to establish relationships among trees based on morphological and pomological parameters. Gas chromatography was used to determine fatty acid composition of 30 cultivar trees and 13 oleaster trees. We determined for one cultivar Gerboui the steady drupe, pit morphological and oil composition variation ranges in six different contrasted agro-systems. SSR genotyping was performed in polyacrylamide gels after fluorescent labelling. Based on morphology, oleaster trees from agro-ecosystems clustered broadly in an intermediate position between cultivars and oleasters from natural ecosystems. SSR revealed that the feral and genuine oleasters plus cultivars are always overlapping. Relationships between cultivars are displayed in two dendrograms. They revealed six and three main clusters based on Unweighted Pair Group Method (UPGMA) and Ward algorithm, respectively. They mix olive cultivar and oleaster trees suggesting kinship relationships between some cultivar and some oleaster trees. In contrast, on PCA, some morphological parameters split our sample approximately between olive and oleaster trees. Oil composition was similar between cultivar and oleaster trees. Kinship relationships between cultivar and oleaster trees based on molecular polymorphisms suggested that olive cultivars may have origin in local oleasters. Oil composition as fruit descriptors and drupe size appeared inefficient to discriminate between olive and oleaster trees, in comparison to SSR. Our results suggested several domestication events for the olive. It is important to know which cultivars have local origin to promote and sale products from Tunisia as from all around the Mediterranean basi

Genotypic differentiation in the stomatal response to salinity and contrasting photosynthetic and photoprotection responses in five olive (Olea europaea L.) cultivars

10 Pags., 2 Figs., 3 Tabls.Olive tree is moderately tolerant to salinity. Differences in salt tolerance among olive tree cultivars are documented. Salt-mediated decreases of stomatal conductance and photosynthesis are common in the studied cultivars, but other photosynthetic characteristics in response to increasing salinity are much less investigated. Greenhouse experiments were conducted to investigate the responses to increasing salinity up to 200mM NaCl of five olive tree cultivars: 'Chemlali', 'Chetoui', 'Arbequina I18', 'Arbosana I43' and 'Koroneiki', widely used in Tunisia. Techniques used include determinations of leaf concentrations of the toxic ions Na and Cl, photosynthetic pigment analyses, gas exchange and chlorophyll (Chl) fluorescence measurements. Relationships between thermal energy dissipation and changes in pigment composition were investigated. With 100mM NaCl water, the most readily available water in arid regions of Tunisia, 'Chemlali', 'Chetoui' and 'Arbosana' grew similarly to control plants, which is a valuable information for horticultural purposes. In all cultivars, leaf Na and Cl concentrations increased and net CO2 assimilation rates decreased as salt concentration increased. A negative correlation was observed between photosynthesis and leaf thickness. Data revealed genotypic differentiation in the stomatal response to salinity, decreasing in 'Koroneiki', 'Arbequina' and 'Arbosana' but remaining fairly constant in 'Chemlali' and 'Chetoui'. In those cultivars where the amount of energy thermally dissipated increased in response to salinity, it was well correlated with increases of (zeaxanthin+antheraxanthin)/(violaxanthin+antheraxanthin+zeaxanthin) ((Z+A)/(V+A+Z)) and lutein to Chl molar ratios. In summary, salinity caused marked reductions in photosynthetic rates well correlated with leaf Na and Cl accumulation. Photosynthesis limitation was partially attributed to stomata closure, except in the cultivars 'Chemlali' and 'Chetoui' in which stomatal conductances were unaltered. Possible decrease of CO2 mesophyll conductance mediated by increases of leaf thickness is discussed. Salinity increased Z+A- and/or lutein-mediated thermal energy dissipation of some of the olive tree cultivars investigated. © 2013 Elsevier B.V.This work was supported by grants from Olive Tree Institute (Tunisia) to Ajmi Larbi and Monji Msallem and AECID (grant AP/040397/11) to Ajmi Larbi and Anunciación Abadía (EEAD-CSIC). Ruth Sagardoy was supported by an I3P-CSIC predoctoral fellowship. Fermín Morales wishes to thank Gobierno de Aragón (A03 Research Group) for financial support.Peer reviewe

Are olive cultivars distinguishable from oleaster trees based on morphology of drupes and pits, oil composition and microsatellite polymorphisms?

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699International audienceThe study aims to determine which traits may help to differentiate cultivars and oleaster trees based on drupe and pit morphological traits, oil content and composition and nuclear DNA markers at seven SSR loci. We determined for one cultivar (Gerboui) the steady drupe, pit morphological and oil composition variation ranges in six different contrasted agro-systems. We then investigated 33 cultivars and 40 oleaster trees. PCA analysis on morphological traits was examined. Gas chromatography was used to determine fatty acid composition of 20 cultivars and 13 oleaster trees, and the Soxhlet method was used to determine fruit oil content. SSR genotyping was performed in poly-acrylamide gels. Five clusters based on UPGMA mixed olive cultivars and oleaster trees suggesting kinship relationships between some cultivars and some oleasters; and thus cultivars could derive from domestication of oleaster trees.L'étude a pour objet de déterminer les caractères permettant de différencier les oléastres et les cultivars d'olivier en se basant sur la morphologie du fruit et du noyau, le contenu et la composition de l'huile, et de la variation génétique à 7 locus SSR. Nous avons au préalable déterminé l'amplitude de la variation morphologique et biochimique induite par l'environnement pour le cultivar Gerboui dans 6 agro-écosystèmes différents. Nous avons ensuite caractérisé 33 cultivars et 40 d'oléastres. La variation morphologique est analysée par ACP, la composition en acides gras par chromatographie en phase gazeuse. Nous avons utilisé la méthode de Soxhlet pour quantifier la teneur en huile de 20 cultivars et 13 oléastres. Les SSR ont été séparés en gel de poly-acrylamide. Cinq groupes d'individus construits selon la méthode UPGMA basés sur les données génétiques suggèrent des parentés étroites entre oléastres et cultivars qui découleraient de domestication locale ou de flux de gènes entre les deux compartiments