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Evaluation of Genetic Intra-Variability and Clonal Selection Within the Main Population Variety (Moroccan Picholine cv) of the Olive Tree (Olea Europaea L.) Grown in Northern Morocco (Ouezzane Region) Using Morphological Descriptors
Abstract
This study aimed to evaluate the genetic variability in the olive tree population (Olea europaea L.) of Ouezzane plantations and identify the performing clones who present interesting agronomic and technological characteristics. The results of studying of agrobiological and technological features of promising clones of olive trees are presented. The numerical values of the main agrobiological characteristics of the clones of the olive. The organoleptic characteristics were summarized. The Statistical analysis (PCA, HCA) showed that the organoleptic proprieties of the fruit and the pit displayed the largest part of the total variance. Six clones S1, S2, M1, M6, G9, and G10, were retained to assess olive fruit and oil production. Among these clones. BM2, BM3, BMM, and BMR were included for exclusively producing oil of remarkable dietary quality. After confirmation of their potentialities by tried comparative trials attempted under different environments. The isolated clones will be multiplied and then distributed to olive growers to establish plantations even the most recent ones.
In this article, we are centrally interested in the products of the olive tree and oleaster in Northern Morocco and in the technical conditions used to obtain table olives and several types of oils, and in what these products represent for the inhabitants. We aim to understand if the Rif offers any peculiarity. We suggest that these techniques, knowledge and expertise on oils have influenced pre-domesticatory and breeding processes in Northern Morocco. We will also discuss the exchanges within the Arabic-speaking groups of the Rif on this subject, and especially between Ain Mediouna who are Jbala Arabic speakers and their neighbors, groups speaking a Bedouin Arabic dialect, the Ḥyayna with whom they exchange regularly. The joint ethnobotanic and linguistic joint approach, through the analysis of certain terms such as məslāl used to describe a type of wild olive oil, zitəl bərri məslāl, shows a binary classification of varieties of oils, which could have led to the selection of varieties of the same name spreading mostly in the North of Morocco. A remarkable diversity of types of oils bear different local names: zīt t-tǝṛyāq, ɛǝlwāna, zīt šāmiyya, zīt d-əl-bərri məslāl, zīt əl-bərri rqīq, zīt d-əl-ma, zīt ɛarūsa, etc. They correspond to extraction processes ranging from the oldest millstones and mills dating from the Neolithic, to the most modern. This diversity suggests that farmers in Northern Morocco have old and significant types of knowledge and know-hows about olive trees and the oleaster, including the mastering of the oleaster grafting techniques. This knowledge, threatened by the industrialization of the oil production in Morocco, are however of heritage value –both culturally and economically- and invaluable for local food security, and the maintenance of the varietal diversification process, a highly topical subject for sustainable development.
Surface morphology and development of the cuticle of olive ( Olea europaea L, cv. Manzanillo) leaves were studied in relation to some factors (wetting, retention) that influence absorption of foliar-applied substances. Cuticle deposition occurred at a uniform rate during leaf development, then ceased at full expansion. The total weight of the cuticular membrane per unit surface area remained constant during leaf expansion. The weight of the cuticular membrane of the adaxial epidermis was about 1.4 mg/cm ² and in μ g/cm ² the principal constituents were: epicuticular wax, 243; cutin, 886; cuticular wax, 272. The thickness of the cuticle was greater on the adaxial (11.5 μ m) than on the abaxial surface (4.5 μ m), and both surfaces were covered with large (130 μ m diameter) peltate trichomes, their number being greater on the abaxial surface (143/mm ² vs. 18/mm ² ). Stomata were present only on the abaxial surface (470/mm ² ). The large number of trichomes contributed significantly to the effective surface area of the leaf, which was about 3 times greater for the abaxial than for the adaxial surface. No epicuticular wax fine-structure was observed. Both surfaces were difficult to wet. The advancing contact angle formed by distilled water was 106° for the adaxial and 125° for the abaxial surface. Retention as indexed by dipping leaves in distilled water was 0.34 μ l/cm ² . When sprayed, maximum retention was 31.3 and 36.9 μl/cm ² by the adaxial and abaxial surfaces, respectively.
Some aspects of Albanian olive: In 1994, the Albanian Olives has olive trees present XV-XVI century, which constitute 15% of the surface. About 3% are with age genotype over 1000 years. Among the main cultivars: cv Kaninjot is pervasive and occupies half the surface. National Olives actually is classified in four groups: (i) antique olives, (ii) extensive olives, (iii) intensive olives, (iv) marginal Olives. A scientific research program is developing. The purpose of research is the economic interest as well have to target a better understanding of the biological cycle and genetic diversity. Three collections intended for testing varietal. The basic principles are the production techniques, the recovery and varietal improvement. Implementation of techniques that improve the quality of our production, Based on the critical periods of the annual cycle in particular: time of harvesting fruit, flowering effort to limit the periodicity:
Archéo-biologie de la domestication de l'olivier en Méditerranée occidentale: de la remise en cause d'une histoire dogmatique à la révélation de son irrigation médiévale. Études héraultaises 233, 13-25 (2009). Archéo-biologie de la domestication de l'olivier en Méditerranée occidentale : de la remise en cause d'une histoire dogmatique à la révélation de son irrigation médiévale Olivier subspontané (féral) dans la région basaltique du Ledja (Syrie). L'arbre a poussé dans une faille au sein de la couche de basalte. Dans la région, des oliviers isolés sont cultivés ça et là, protégés du bétail par des « tours » de pierres sèches, et dans des oliveraies là où l'espace dégagé est suffisamment grand.] Février 2007. Cliché J.-P. Moussally.
Iran, located in the Eastern Mediterranean, shares many geographical characteristics and common historical roots with the countries of the Mediterranean basin, which are home to the major known cultivars of olive. Iran, for its part, harbors numerous olive cultivars, whose morphological and biological characters are yet to be characterized. This is important both from commercial and nutritional points of view. Building upon earlier work and in conjunction with a molecular genetics program for molecular characterization of Iranian olive cultivars, we under- took to characterize olive germplasm of Iran on the basis of morphological charac- ters. To reach this goal, we started our research with the study of two important cultivars in Iran, 'Zard' and 'Rowghani'. This survey was performed over a one-year period. Samples were gathered from 281 ('Zard', 212 and 'Rowghani', 69) adult trees in eight regions with different ecological condition in the North of country (Roodbar, Manjil, Aliabad, Joodaki, Vakhman, Bahramabad, and Gilvan). Forty samples of flower, fruit, endocarp and leaf were collected from each tree. Multivariate statistical methods including cluster analysis and Principal Component Analysis were used for data analysis. Our preliminary results indicate a considerable variation within the traditionally recognized cultivars of olive in Iran. A more detailed assessment of morphological characters is in progress.
Synopsis
Actual transpiration decreased with decreasing soil moisture content and increasing potential transpiration. Average soil suction in the root zone when the actual transpiration rate fell below the potential rate varied from 12 bars when the potential transpiration rate was 1.4 mm. per day to 0.3 bar when the potential rate was 6 to 7 mm. per day.
Rapid technological changes in olive growing have increased interest in breeding programs and new cultivars. A breeding program aimed at selecting new dual purpose (i.e. oil and table olive) cultivars began in Italy in 1971. In this paper we describe the agronomic performance (i.e. fruit and oil yield, fruit size, pulp to pit ratio, and oil content) of 134 olive selections grown in three locations of central and southern Italy . Twenty-one genotypes were selected as candidates for possible new cultivars based on their higher yield and yield efficiency. Data on many genotypes allowed assessment of variability of the studied traits in olive. The presence of many genotypes at all three locations, having different climates, allowed a quantitative analysis of the environmental (E 2 ) vs. the genotypic (heritability: H 2 ) effects on some traits in olive. Both environment and genotype had signi - ficant effects on all parameters tested. E 2 was greaterthan H 2 for average fruit weight and oil content on a fresh matter basis, while oil content on a dry matter basis and pulp to pit ratio were mainly under genetic control.
This study was conducted to evaluate the quantitative and qualitative effects of partial rootzone drying (PRD) irrigation on olive trees and their fruit and oil quality. Olive trees of the Moroccan Picholine variety were grown under arid conditions in Marrakech, and exposed to four irrigation treatments: Control (irrigated with 100 % of the crop evapotranspiration, on the two sides of the root system), PRD1 (irrigated with 50 % of the control, on one side of the root system, switching every two weeks), PRD2 (irrigated with 50 % of the control, on one side of the root system, switching every four weeks) and PRD3 (irrigated with the same amount of water as the control applied on one side of the root system, switching every two weeks). The individual fruit weight, dimensions and oil contents were generally greater under PRD than the control. Whereas, the fruit water content was lower under PRD1 and PRD2 than the control and PRD3. Oil acidity was not affected by irrigation, while the total polyphenol content, which affects the oxidative stability and sensory characteristics of the oil, increased in response to the PRD irrigation, especially under PRD1 (246.0 ppm) and PRD2 (278.5 ppm) treatments, against 148.4 ppm and 101.8 ppm for PRD3 and the control respectively. This increase could explain the oil bitterness observed under PRD1 and PRD2. The fatty acid composition was not affected by PRD1 and PRD2. The oil quality based on UV absorption coefficients (K232 and K270) decreased significantly under PRD2. Chlorophyll content and maturity index were antagonistic, and olive ripeness was found to be precocious under PRD irrigation treatments compared to the control.
De l’olivier à l’oléastre : origine et domestication de l’Olea europaea L. dans le Bassin méditerranéen Keywords : VEGETAL PRODUCTIONS, NATURAL RESOURCES AND ENVIRONMENTRésumé : L’olivier occupe la 24 e place des 35 espèces les plus cultivées dans le monde. La diversité phénologique des cultivars est remarquable et l’intérêt économique de l’espèce est majeur. Pourtant peu d’études ont porté sur la domestication de l’olivier et sur les relations entre l’olivier et sa forme sauvage, l’oléastre. Les marqueurs moléculaires rendent possible l’étude de la structure génétique des cultivars, des flux géniques et des relations entre la forme cultivée et sauvage. L’analyse de la diversité actuelle de la sous-espèce europaea d’Olea europea permet de remonter le temps et d’analyser les mécanismes qui ont conduit à cette diversité. Les processus utilisés donnent un panorama de la diversité après les glaciations et permettent de situer globalement les zones refuges qui apparaissent nombreuses et génétiquement très structurées. La comparaison avec la connaissance populaire montre que, chez cette espèce, l’histoire a été enjolivée, probablement pour combler l’absence de données historiques. L’origine de l’olivier à partir de l’oléastre ne fait plus de doute à l’est comme à l’ouest de la mer Méditerranée. Cependant, la diversité de l’oléastre et de l’olivier est maximale à l’ouest. L’archéologie confirmant la présence de l’oléastre à l’ouest, l’origine de la sous-espèce europaea est donc à reconsidérer
To assess the genetic diversity in Moroccan cultivated olive, Olea europaea L. subsp. europaea, we performed molecular analysis of olive trees sampled in four geographic zones representing all areas of traditional olive
culture. The analysis of 215 trees using 15 simple sequence repeat (SSR) loci revealed 105 alleles distributed among 60 SSR
profiles. The analysis of chloroplast deoxyribonucleic acid polymorphism for these 60 olive genotypes allowed to identify
four chlorotypes: 42 CE1, one CE2, nine COM1 and eight CCK. Among the 60 SSR profiles, 52 corresponded to cultivated olive
trees for which neither denomination nor characterisation is available. These local olive genotypes displayed a spatial genetic
structuring over the four Moroccan geographic zones (northwest, north centre, Atlas and southwest), as pairwise Fst values ranged from 0.0394 to 0.1383 and varied according to geographic distance. As single alleles detected in local olive
were also observed in Moroccan oleaster populations, results suggest that plant material was mainly selected from indigenous
populations. The assumption that Picholine marocaine cultivar is a multi-clonal cultivar was not supported by our data because
we found a single genotype for 112 olive trees representing 31 to 93% of the olives sampled locally in the 14 different areas.
Picholine marocaine and the few other named cultivars do not seem to belong to the same gene pools as the unnamed genotypes
cultivated only locally. The situation is paradoxical: a substantial genetic diversity in Moroccan olive germplasm, probably
resulting from much local domestication, but a single cultivar is predominant.
Gas exchange rates, chlorophyll fluorescence, pressure–volume relationships, photosynthetic pigments, total soluble sugars,
starch, soluble proteins and proline concentrations were investigated in five Olea europaea L. cultivars with different geographical origins (Arbequina, Blanqueta, Cobrançosa, Manzanilla and Negrinha) grown under
Mediterranean field conditions. We found considerable genotypic differences among the cultivars. Comparing the diurnal gas
exchange rates, we observed that Cobrançosa, Manzanilla and Negrinha had high photosynthetic rate than Arbequina and Blanqueta.
The first group reveals to be better acclimated to drought conditions, and appears to employ a prodigal water-use strategy,
whereas Blanqueta and Arbequina, with high water-use efficiency, appear to employ a conservative water-use strategy. The degree
of midday depression in photosynthesis was genotype dependent, with a maximum in Arbequina and a minimum in Negrinha. The
reductions in the photosynthetic rate were dependent from both stomatal and non-stomatal limitations. Elastic adjustment plays an important role as drought tolerance mechanism. The group of cultivars that employ a prodigal
water-use strategy revealed high tissue elasticity, whereas Arbequina and Blanqueta revealed high tissue rigidity. We also
identified the existence of drought tolerance mechanisms associated with soluble proteins accumulation in the foliage. The
high levels of soluble proteins in Arbequina may represent an increased activity of oxidative stress defence enzymes and may
also represent a reserve for post stress recovery. In all cultivars, especially in Manzanilla, free proline was accumulated
in the foliage. The discussed aspects of drought stress metabolism may have an adaptative meaning, supporting the hypothesis
that olive cultivars native to dry regions, such as Cobrançosa, Manzanilla and Negrinha, have more capability to acclimate
to drought conditions than cultivars originated in regions with a more temperate climate, like Arbequina and Blanqueta.
One hundred and two olive RAPD profiles were sampled from all around the Mediterranean Basin. Twenty four clusters of RAPD
profiles were shown in the dendrogram based on the Ward’s minimum variance algorithm using chi-square distances. Factorial
discriminant analyses showed that RAPD profiles were correlated with the use of the fruits and the country or region of origin
of the cultivars. This suggests that cultivar selection has occurred in different genetic pools and in different areas. Mitochondrial
DNA RFLP analyses were also performed. These mitotypes supported the conclusion also that multilocal olive selection has occurred.
This prediction for the use of cultivars will help olive growers to choose new foreign cultivars for testing them before an
eventual introduction if they are well adapted to local conditions.
A mild water stress was imposed upon potted tangerine trees (Citrus sinensis Blanco. cv. Zhuju) by water withholding during early juice sac expansion stage. While fruit growth was inhibited by water stress a growth potential was built up inside the fruit, which was not expressed until re-watering. The more powerful water uptake force of the stressed fruit was caused by its more negative fruit water potential. The mechanisms involved were both passive and active in nature: more water loss from fruit to transpiring leaves during water stress and some active adaptive physiological responses of fruit to water stress. The physiological responses involved both osmotic adjustment and cell wall adjustment. The former was reflected in higher soluble solute contents in both fruit juice and fruit skin (on a dry weight basis) resulting in the drop of osmotic potential (ψs). The latter was reflected in the cell wall loosening of fruit skin in response to water stress causing a further fruit turgor (ψs) drop. These two responses further reduced fruit water potential, which promoted post-stress fruit expansion growth.
Glacial refuge areas are expected to harbor a large fraction of the intraspecific biodiversity of the temperate biota. To test this hypothesis, we studied chloroplast DNA variation in 22 widespread European trees and shrubs sampled in the same forests. Most species had genetically divergent populations in Mediterranean regions, especially those with low seed dispersal abilities. However, the genetically most diverse populations were not located in the south but at intermediate latitudes, a likely consequence of the admixture of divergent lineages colonizing the continent from separate refugia.
The magnitudes of the systematic biases involved in sample heterozygosity and sample genetic distances are evaluated, and formulae for obtaining unbiased estimates of average heterozygosity and genetic distance are developed. It is also shown that the number of individuals to be used for estimating average heterozygosity can be very small if a large number of loci are studied and the average heterozygosity is low. The number of individuals to be used for estimating genetic distance can also be very small if the genetic distance is large and the average heterozygosity of the two species compared is low.
Les oliviers cultivés et leurs parents sauvages (oléastres), représentent deux variétés botaniques de l'espèce Olea europaea, subsp. var. europaea et var. sylvestris, respectivement. Selon des études génétiques et archéobotaniques antérieures, l'existence de populations d'oléastres dans l'est et l'ouest du bassin méditerranéen remonte à avant le néolithique. La domestication de l'olivier aurait eu lieu au moins dans ces deux zones. Néanmoins, la lignée maternelle qui caractérise les oléastres de l'est de la Méditerranée est majoritaire au sein des variétés méditerranéennes. Une telle signature génétique est probablement le résultat de migrations humaines essentiellement d'est en ouest. En dépit de ces travaux, les origines et les processus de diversification à l'ouest de la méditerranée demeurent méconnus. L'objectif de cette thèse est d'étudier les origines et les processus de diversification chez l'olivier à l'ouest de la Méditerranée. Deux hypothèses sont formulées: (i) une co-existence entre variétés sélectionnées localement et variétés introduites à partir de l'est de la Méditerranée et maintenues par clonage, (ii) une sélection à partir des formes de l'est introgressées par les populations locales à l'ouest de la Méditerranée. Dans une première partie, nous avons examiné les processus de diversification par une analyse des pratiques paysannes à une échelle localisée et dans une zone d'extrême diffusion : le Maroc. Il s'agissait de comprendre comment les paysans traitent la diversité variétale dans un contexte fortement impacté par une seule et même variété, la ‘Picholine marocaine'. Sur la base d'enquêtes semi-dirigées menées auprès des paysans dans les agro-écosystèmes traditionnels et selon une approche d'ethnobiologie, nous avons mis en évidence l'importance des logiques de classifications locales (usage, origine, âge, conservation de l'huile, méthode de propagation…) dans le traitement, le maintien et la gestion de la diversité variétale. Nos résultats montrent la présence d'un système de dénomination basée sur des catégories englobantes où les types d'oliviers sont regroupés sous des noms génériques en fonction des critères socioculturels et techniques plutôt que sur des critères morphologiques. Nous avons montré que ces catégories sont définies par des contours permissifs permettant aux types d'oliviers d'être classées dans plusieurs catégories. Nous soutenons l'hypothèse que ce système de classification permet de maintenir la diversité et est une force motrice pour la diversification variétale dans ces agro-écosystèmes caractérisés par une faible diversité d'oliviers. Dans une seconde partie, nous avons examiné les processus de diversification variétale par une approche basée sur la phylogéographie à l'échelle de la Méditerranée. Les analyses génétiques des variétés méditerranéennes d'olivier basées sur l'utilisation des marqueurs microsatellites nucléaires et chloroplastiques selon une approche bayésienne montrent une structure génétique est-ouest. La plupart des variétés de l'ouest de la méditerranée ont une lignée maternelle de l'est mais un génome nucléaire proche du "pool" génétique de l'ouest de la Méditerranée, ce qui indique une sélection à partir des formes de l'est introgressées par le "pool" génétique ouest et suggère que la sélection des oliviers à partir du semis n'a pas cessé aux premières étapes de domestication. Nos analyses sur les pratiques paysannes montrant que l'oléastre issu de semis fait partie intégrante de l'agro-écosystème et fait l'objet de sélection et d'usage (greffage sur oléastre, utilisation de l'huile de l'oléastre), ce qui plaide en faveur de l'hypothèse de l'introgression. En adoptant l'approche ABC (Approximative Bayesianne Computation), nous montrons que le scénario basé sur l'introgression des oliviers de l'est par les oléastres de l'ouest est le plus probable avec une introgression. Nous proposons un nouvel éclairage sur les processus de domestication à l'ouest de la Méditerranée en croisant les analyses des pratiques paysannes à celles de la phylogéographie de l'olivier dans le bassin méditerranéen. Nous discutons ces résultats vis-à-vis de la conservation ex-situ versus in-situ et en rapport avec les questions soulevées par l'évolution de la diversité des plantes impliquant une multiplication végétative et la reproduction sexuée.
Ethylene in Plant Biology, Second Edition provides a definitive survey of what is currently known about this structurally simplest of all plant growth regulators. This volume contains all new material plus a bibliographic guide to the complete literature of this field. Progress in molecular biology and biotechnology as well as biochemistry, plant physiology, development, regulation, and environmental aspects is covered in nine chapters co-authored by three eminent authorities in plant ethylene research. This volume is the modern text reference for all researchers and students of ethylene in plant and agricultural science. Key Features * Completely updated * Concise, readable style for students and professional * Contains an extensive bibliographic guide to the original literature * Well illustrated with diagrams and photographs * Thorough coverage of: * ethylene and ethephon roles and effects * stress ethylene * biosynthesis of ethylene * molecular biology of ethylene * action of ethylene * agricultural uses of ethylene.
Twenty-five cultivars of Olea europaea were compared with respect to electro- phoretically detectable differences at 15 enzyme systems. The genetic distances between all pairs of cultivars (based on the identity of proteins) have been calculated. A ‘phylogeny’ is derived from these data and discussed in the light of new archaeological findings concerning olive cultivation and other historical evidence.
Olive accessions collected in Lake Garda, one of the northernmost olive growing districts in the world, were characterised by a combination of morphological traits, chemical analysis of oils and AFLP-DNA markers. Among the more relevant accessions, other than the very well-known cultivars 'Casaliva', 'Frantoio', 'Leccino' and 'Pendolino', the local 'Baia', 'Mitria' and 'Regina' should be regarded as interesting for both horticultural and oil quality traits.
Water movement in response to gradients of water potential in the soil-plant-atmosphere catena is considered. An approximate solution is presented of the differential equation describing soil moisture flow towards a plant root which is absorbing water at a periodically varying rate. This is combined with hypothetical plant characteristics to form a model of the hydraulic behaviour of a crop. The characteristics specified are the depth of penetration of roots into the soil, the density of rooting (length of root per cm3 of soil volume), the internal resistance of the crop to the flow of water and the critical value of leaf water potential which is associated with stomatal closure. The level of leaf water potential in relation to environmental conditions, and the rate of transpiration from the crop when leaf water potential falls to the critical value, are determined by the `supply function' which is a measure of the ability of the soil-crop system to supply water to the evaporating surfaces within the leaves. The variation of this function with the water content of the soil is examined for different values of the parameters involved, and the behaviour of the soil-crop model under constraints representing those imposed by the external environment is discussed.
The genus Olea is revised. 33 species and nine subspecies are recognized in three subgenera: Olea, Tetrapilus and Paniculatae, the first with two sections: Olea and Ligustroides. Three new taxa are recognized: subgen. Tetrapilus, subgen. Paniculatae and Olea woodiana subsp. disjuncta. Keys, descriptions, the citation of specimens and an index to exsiccatae are provided.
A field study was conducted to evaluate effects of plant water stress at different stages of growth on grain and forage yields and yield components of grain sorghum [ Sorghum bicolor (L.) Moench]. Irrigated grain sorghum was subjected to various periods of plant water stress beginning at (i) early boot, (ii) heading, and (iii) early grain filling. Unstressed sorghum yielded 7,410 kg grain/ ha. Stress periods of 13 to 15 days [average afternoon leaf water potentials (LWP) −15.8 to −20.3 bars] did not reduce grain yields but, 27− to 28‐day stress periods (average afternoon LWP, −21.7 bars) beginning at early boot or heading stages reduced yields 27%. However, a 27‐day stress period (average afternoon LWP, −22.7 bars) beginning at early grain filling reduced yields only 12%. Thirty.five and 42‐day stress periods (average afternoon LWP, −22.9 and −24.0 bars), beginning at boot stage reduced yields 43 and 54%, respectively. Yield reductions from stress initiated at early boot stage resulted from both reduced seed size and seed numbers. When stress was imposed at heading or later, only seed size was reduced. Forage yields were not affected by 27‐ to 28‐day stress periods but were reduced by stress periods imposed at early boot stage and extended for 35 or 42 days.
The effects of soil drying on leaf water relations and gas exchange were studied in quinoa grown in pots with sandy soil and in lysimeter plots with sandy loam in the field. Midday values of leaf water potential (ψl), leaf osmotic potential (ψπ), relative water content (RWC), leaf conductance (gl), light saturated net photosynthesis (Asat), and specific leaf area (SLA) were determined in fully watered and droughted plants. At branching, flowering and grain filling gl in leaves of fully watered plants varied from 0.3 to 1.0, 0.3 to 0.6 and 0.2 to 0.7 mol m2 s−1 and Asat varied from 18 to 34, 14 to 24 and 8 to 26 μmol m2 s−1. In droughted plants stomatal closure began when leaf water potential (ψl) decreased below −1.2 to −1.6 MPa and Asat was reduced to 5–10 μmol m2 s−1 as a result of stomatal closure, when ψl decreased to −1.5 to −2.0 MPa. The osmotic potential at full turgor (ψπ100) decreased by age from −1.0 to −1.4 MPa. During severe water stress quinoa maintained positive turgor down to a zero turgor leaf water potential value (ψl0) of −1.8 MPa. Quinoa had a limited osmotic adjustment ψπ100 between fully watered and droughted plants being 0.3–0.4 MPa at the most. During branching the turgid weight/dry weight (TW/DW) ratio decreased from 9 to 5. At flowering and grain filling the TW/DW ratio was low (4–6). The bulk elastic modulus (εmax) determined at the beginning of the grain filling period was medium to high (18–22 MPa). SLA was high (23–21 m2 kg−1) during branching and decreased during the later growth stages. Conclusively, both high net photosynthesis rates and SLA values during early vegetative growth probably result in early vigour of quinoa supporting early water uptake and thus tolerance to a following drought. The stomatal response of quinoa was insensitive to drought induced decrease of leaf water status. The leaf water relations were characterised by low osmotic potentials and low TW/DW ratios during later growth stages sustaining a potential gradient for water uptake and turgor maintenance during soil drying.
Aim The oleaster is believed to have originated in the eastern Mediterranean, implying that those in the western Mediterranean basin could be feral. Several studies with different molecular markers (isozymes, random amplified polymorphic DNA, amplified fragment length polymorphism) have shown a cline between the eastern and the western populations, which supports this hypothesis. To reconstruct the post‐glacial colonization history and establish a relationship between olive and oleaster populations in the Mediterranean basin, analyses were carried out on the genetic variation of chloroplast DNA (chlorotype) and at 12 unlinked simple sequence repeat (SSR) loci, sampling a total of 20 oleaster groves.
Location This is the first known large‐scale molecular study of SSR loci based on samples of both oleasters and cultivars from the entire Mediterranean basin.
Methods Samples were taken from 166 oleasters in 20 groves of modern populations, and 40 cultivars to represent molecular diversity in the cultivated olive. The Bayesian method and admixture analysis were used to construct the ancestral populations (RPOP; reconstructed panmictic oleaster populations) and to estimate the proportion of each RPOP in each tree. If one tree can be assigned to two or more RPOPs, it can be regarded as a product of hybridization between trees from different populations (i.e. admix origin).
Results On this first examination of the SSR genetic diversity in the olive and oleaster, it was found to be structured in seven RPOPs in both eastern and western populations. Based on different population genetic methods, it was shown that: (1) oleasters are equally present in the eastern and the western Mediterranean, (2) are native, and (3) are not derived from cultivars. Chlorotypes (one and three in the eastern and western Mediterranean, respectively) revealed fruit displacement for the oleasters.
Main conclusions Oleaster genetic diversity is divided into seven regions that could overlay glacial refuges. The gradient, or cline, of genetic diversity revealed by chloroplast and SSR molecular markers was explained by oleaster recolonization of the Mediterranean basin from refuges after the last glacial event, located in both eastern and western regions. It is likely that gene flow has occurred in oleasters mediated by cultivars spread by human migration or through trade. Animals may have helped spread oleasters locally, but humans have probably transported olives but not oleaster fruits over long distances. We found that cultivars may have originated in several RPOPs, and thus, some may have a more complex origin than expected initially.
Stomatal behaviour, leaf water status and photosynthetic response in relation to long-term water deficit were investigated in southern Italy on young trees of Olive (Olea europaea) to clarify mechanisms of stomatal control. Trees were subjected to three irrigation treatments, T0, T33 and T66 that received 0, 33 and 66%, respectively, of crop evapotranspiration by a drip irrigation system. The prolonged drought during the summer significantly affected soil and leaf water status and gas exchange. In the unirrigated treatment, the drought decreased volumetric soil water content from 30 to 21%, midday leaf water potential from −1.5 to −3.4 MPa, relative water content from 84 to 74% and stomatal conductance to water vapour from 0.190 to 0.023 mol m−2 s−1. Similar responses to milder water deficit were observed for the irrigated treatments. Good positive relationships were found between stomatal conductance and both leaf water potential and soil moisture. This indicates that both hydraulic feedback and feed-forward mechanisms could be invoked in the response of stomata to soil drying. In late summer, a significant re-increase in both leaf water potential and relative water content was observed in the absence of significant rainfall. Conversely, stomatal conductance remained at quite a low value as did soil moisture. The disruption of the positive relationship between stomatal conductance and leaf water potential at constant soil moisture clearly indicates that soil or root water status directly affected stomatal conductance, minimising the possibility of a feedback mechanism through leaf water status. Photosynthetic CO2 assimilation in T0 decreased during the season from 14 to 3.3 μmol m−2 s−1, the minimum value that was found in correspondence with minimum leaf water potential and soil moisture. The response curve of assimilation to intercellular CO2 partial pressure showed that photosynthetic metabolism was greatly depressed by long-term water deficit, with a reduction of 48% for the slope at low CO2 and of 67% for photosynthetic assimilation at high CO2, and that it played a greater role than stomata in limiting photosynthesis.
Changes in anatomy, sclerophylly, pressure–volume relationships, chemical composition and oxidative stress symptoms were studied in leaves of three Olea europaea L. cultivars (Cobrançosa, Madural and Verdeal Transmontana), submitted to contrasting water availability regimes. Anatomically, Cobrançosa and Madural were more capable than Verdeal Transmontana to cope with low water (LW) availability, with a thicker upper epidermis, a thicker palisade parenchyma and a higher stomatal density. Cobrançosa leaves also revealed the lowest specific leaf area and the highest density of the foliar tissue. Under LW conditions, Cobrançosa and Madural showed greater capability for osmotic adjustment and increased tissue rigidity. By contrast, Verdeal Transmontana did not exhibit osmotic adjustment, but was able to increase tissue elasticity and total soluble protein concentration. Leaves grown under LW conditions revealed signs of oxidative stress, with decreases in chlorophyll, carotenoid and total thiol concentrations and increased levels of lipid peroxidation. Nevertheless, LW plants developed some defense mechanisms against oxidative stress, like the increase in total phenol and total soluble protein concentrations. Comparatively, Cobrançosa revealed more protection against oxidative stress. In opposition, the increased levels of lipid peroxidation and the decreased total thiol concentration under LW conditions suggest that the mechanisms against oxidative stress were less effective in Madural.
The article reviews the available information on the start of fruit tree cultivation in the Old World. On the basis of (i) evaluation of the available archeological remains and (ii) examination of the wild relatives of the cultivated crops, it was concluded that olive, grape, date, and fig were the first important horticultural additions to the Mediterranean grain agriculture. They were most likely domesticated in the Near East in protohistoric time (fourth and third millennia B.C.) and they emerge as important food elements in the early Bronze Age.
Domestication of all four fruit trees was based on a shift from sexual reproduction (in the wild) to vegetative propagation of clones (under domestication). Olive, grape, date, and fig can be vegetatively propagated by simple techniques (cuttings, basal knobs, suckers) and were thus preadapted for domestication early in the development of agriculture.
The shift to clonal propagation placed serious limitations on selection and on fruit set under cultivation. We have examined the consequences of this shift in terms of the genetic makeup of the cultivars and traced the various countermeasures that evolved to ensure fruit set.
Finally, it was pointed out that in each of these classic fruit trees we are confronted with a variable complex of genuinely wild types, secondary weedy derivatives and feral plants, and groups of the domesticated clones, which are all interfertile and interconnected by occasional hybridization. It was concluded that introgression from the diversified wild gene pool facilitated the rapid buildup of variation in the domesticated crops.
Le vin et l’huile dans la
- J P Brun
Dangerous liaisons? When cultivated plants mate with their wild relatives
- N C Ellstrand
L’olivier, techniques agricoles et productions méditerranéennes
- R Loussert
- G Brousse
Croissance. fructification et leur interaction sur la production chez la Picholine Marocaine
- B Boulouha
Les variétés d’olivier cultivés en Espagne. Olivae 9
- D Barranco
- L Rallo
Les produits oleicoles et les regimes méditerraneens. Forum sur la qualité des produits de l’olivier et l’environnement. Salon international de l’olivier, Olea
- F A Mercedes
Les exigences agroclimatiques de l'olivier-IV cours international sur les nouvelles techniques oléicoles, ENA Meknès, Maroc, 19-30 Avril
- R Loussert
Caractérisation genetique, morpholofique et évaluation agronomique: Apport à la certification des plants d’olivier. Séminaire international sur la multiplication et certification des plants d’olivier. un nouvel enjeu pour l’oléiculture du 3ème millénaire
- N Ouazzani
- A Idrissi
- I Belkoura
- S Sghir
Adaptation et évolution de l'olivier et de l'oléastre dans diverses conditions d'isolement. de culture et d'environnement
- C Breton
Analyse de la variabilité de l’AND chloroplastique par RFLP chez l’olivier sauvage et cultivé (Olea europea L.) et relations phylogénétiques dans le genre Olea
- M Amane
Statut génétique des oliviers spontanés exploités pour l’huile d’olive au Nord du Maroc. Communication orale. 3. Congrès International Amélioration de la Production Agricole (APA3): Plan Maroc Vert une vision intégrée pour la qualification de l’Agriculture Marocaine
- A Moukhil
- H Haouane
- S Santoni
- C El Modafar
- B Khadari
Journée Olivier-La recherche agronomique et la profession pour un développement durable de l’oléiculture nationale
- A Lansari
Evaluation agronomique et caractérisation génétique de 20 génotypes d’olivier présélectionnés dans la région de Moulay Driss Zerhoun pour leurs performances de production
- A Elyartaoy