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Growth control and productive aptitude of Olive tree (Olea europaea L.)
No full textOptimizing vegetative growth and canopy architecture is crucial for olive tree productivity. The vegetative growth is linked with the root systems, vital for anchorage and nutrient uptake, and in olive it exhibits plasticity and deep exploration strategies against abiotic stress. Leaf structural changes under abiotic stress contributing to olive tree resilience. 1-year-old shoots are the most mainly organs for the production, in fact, in this organ we can find the potentially reproductive buds.
Therefore the 1-year-old shoot growth is crucial for effective management of reproductive growth and fruit production, given the complexity of olive flower and inflorescence development. The latter are influenced by several environmental conditions, biochemicals endogenous signals, cultivar traits, and nutrient availability. After flowering, fruit development happens, and it is a greater sink organ than vegetative growth. Fruit growth dynamics follow a double-sigmoid curve, with water stress during early development impacting final fruit volume, highlighting the importance of irrigation strategies like Regulated Deficit Irrigation (RDI) for optimizing fruit yield and oil production.
Nutrient management is essential for consistent and sustainable olive production, with fertilization supporting vegetative and fruit growth driven by key nutrients like nitrogen, phosphorus, and potassium, as well as micronutrients influencing flowering and fruit development. Fertilization strategies should consider factors like nutrient availability, soil analysis, and leaf diagnosis for optimal tree health and production, while sustainable practices, including the use of wastewater and biological solutions, enhance nutrient availability while minimizing environmental impact.
In the context of olive tree productivity, light availability plays a significant role, with shading potentially reducing photosynthesis early in the season. Anti-insect or anti-hail nets provide beneficial shading while serving multiple purposes in olive cultivation, contributing to overall orchard management and emphasizing the interconnectedness of various factors in optimizing olive production.
In modern olive cultivation, precise irrigation management is essential. Trunk-embedded microtensiometers offer real-time monitoring of trunk water potential, optimizing water usage. Irrigation is not enough to increase vegetative growth and production, so adequate nutrient levels are crucial for plant health and frost tolerance, mitigating vulnerability to intensified frost events due to climate change.
Frost damage can exacerbate susceptibility to diseases like olive knot, caused by bacteria such as Pseudomonas savastanoi pv. savastanoi. Cultivar susceptibility varies, emphasizing the need for holistic management practices.
Against pests and abiotic stresses, innovative solutions like anti-insect nets can regulate light exposure and enhancing productivity in olive orchards
Growth control and productive aptitude of Olive tree (Olea europaea L.)
Full text linkOttimizzare la crescita vegetativa e l’architettura della chioma è cruciale per la produttività dell’olivo. La crescita vegetativa è collegata ai sistemi radicali, vitali per l’ancoraggio e l’assorbimento dei nutrienti, e nell’olivo mostra plasticità e strategie di esplorazione profonda contro lo stress abiotico. Anche le foglie mostrano una certa plasticità sotto stress abiotico contribuendo alla resilienza dell’olivo a tali stress. I germogli di un anno sono gli organi principali per la produzione dei frutti, infatti, in questo è l’unico organo in cui possiamo trovare le gemme che potenzialmente potranno dar vita alle infiorescenze. Pertanto, la crescita dei germogli di un anno è cruciale per una gestione efficace della parte riproduttiva della pianta, data la complessità dello sviluppo dei fiori e delle infiorescenze dell’olivo. Questi ultimi sono influenzati da diverse condizioni ambientali, segnali biochimici endogeni, caratteristiche delle cultivar e disponibilità di nutrienti. Dopo la fioritura, avviene lo sviluppo del frutto, che è un organo maggiormente “sink” rispetto alla crescita vegetativa. La dinamica della crescita del frutto segue una curva a doppia sigmoide. Lo stress idrico durante lo sviluppo iniziale impatta sul volume finale del frutto, evidenziando l’importanza di strategie di irrigazione come l’Irrigazione a Deficit Controllato (RDI) per ottimizzare il rendimento del frutto e la produzione di olio. La gestione dei nutrienti è essenziale per una produzione di olive coerente e sostenibile, con la fertilizzazione che supporta la crescita vegetativa e del frutto guidata da nutrienti chiave come azoto, fosforo e potassio, così come micronutrienti che influenzano la fioritura e lo sviluppo del frutto. Le strategie di fertilizzazione dovrebbero considerare fattori come la disponibilità di nutrienti, l’analisi del suolo e la diagnosi fogliare per una salute ottimale dell’albero e produzione, mentre pratiche sostenibili, inclusi l’uso di acque reflue e soluzioni biologiche, migliorano la disponibilità di nutrienti minimizzando l’impatto ambientale. Nel contesto della produttività dell’olivo, la disponibilità di luce gioca un ruolo significativo, con l’ombreggiatura che potenzialmente riduce la fotosintesi all’inizio della stagione. Reti anti-insetto o anti-grandine forniscono un’ombreggiatura che può aumentare le prestazioni della pianta, servendo anche a scopi multipli nella coltivazione dell’olivo, contribuendo alla gestione complessiva dell’oliveto. Nella coltivazione moderna dell’olivo, una gestione precisa dell’irrigazione è essenziale. Microtensiometri incorporati nel tronco offrono un monitoraggio in tempo reale del potenziale idrico del tronco, ottimizzando l’uso dell’acqua. L’irrigazione non è sufficiente per aumentare la crescita vegetativa e la produzione; quindi, livelli adeguati di nutrienti sono cruciali per la salute della pianta e la tolleranza al gelo, mitigando la vulnerabilità agli eventi di gelo intensificati a causa del cambiamento climatico. I danni da gelo possono esacerbare la suscettibilità a malattie come la rogna dell’olivo, causato da batteri come Pseudomonas savastanoi pv. savastanoi. La suscettibilità delle cultivar varia, enfatizzando la necessità di pratiche di gestione olistiche. Inoltre, contro i parassiti e gli stress abiotici, soluzioni innovative come le reti anti-insetto possono regolare l’esposizione alla luce e migliorare la produttività negli oliveti.Optimizing vegetative growth and canopy architecture is crucial for olive tree productivity. The vegetative growth is linked with the root systems, vital for anchorage and nutrient uptake, and in olive it exhibits plasticity and deep exploration strategies against abiotic stress. Leaf structural changes
under abiotic stress contributing to olive tree resilience. 1-year-old shoots are the most mainly organs for the production, in fact, in this organ we can find the potentially reproductive buds. Therefore the 1-year-old shoot growth is crucial for effective management of reproductive growth and fruit production, given the complexity of olive flower and inflorescence development. The latter are influenced by several environmental conditions, biochemicals endogenous signals, cultivar traits, and nutrient availability. After flowering, fruit development happens, and it is a greater sink organ than vegetative growth. Fruit growth dynamics follow a double-sigmoid curve, with water stress during early development impacting final fruit volume, highlighting the importance of irrigation strategies like Regulated Deficit Irrigation (RDI) for optimizing fruit yield and oil production. Nutrient management is essential for consistent and sustainable olive production, with fertilization supporting vegetative and fruit growth driven by key nutrients like nitrogen, phosphorus, and potassium, as well as micronutrients influencing flowering and fruit development. Fertilization
strategies should consider factors like nutrient availability, soil analysis, and leaf diagnosis for optimal tree health and production, while sustainable practices, including the use of wastewater and biological solutions, enhance nutrient availability while minimizing environmental impact. In the context of olive tree productivity, light availability plays a significant role, with shading potentially reducing photosynthesis early in the season. Anti-insect or anti-hail nets provide beneficial shading while serving multiple purposes in olive cultivation, contributing to overall orchard management and emphasizing the interconnectedness of various factors in optimizing olive production. In modern olive cultivation, precise irrigation management is essential. Trunk-embedded microtensiometers offer real-time monitoring of trunk water potential, optimizing water usage. Irrigation is not enough to increase vegetative growth and production, so adequate nutrient levels are crucial for plant health and frost tolerance, mitigating vulnerability to intensified frost events due to climate change. Frost damage can exacerbate susceptibility to diseases like olive knot, caused by bacteria such as Pseudomonas savastanoi pv. savastanoi. Cultivar susceptibility varies, emphasizing the need for holistic management practices. Against pests and abiotic stresses, innovative solutions like anti-insect nets can regulate light exposure and enhancing productivity in olive orchards
Continuous Third Phase Fruit Monitoring in Olive with Regulated Deficit Irrigation to Set a Quantitative Index of Water Stress
Full text linkThe transversal fruit diameter (FD) was monitored continuously by automatic extensimeters (fruit gauges) in order to monitor fruit growth dynamics under deficit irrigation treatments. The daily diameter fluctuation (ΔD, mm), the daily growth (ΔG, mm), the cumulative fruit growth (CFG, mm), and the fruit relative growth rate (RGR, mm mm−1 h−1) of four olive cultivars (Ascolana dura, Piantone di Falerone, Arbequina, and Lea) were studied during the third phase of fruit growth. Two regulated deficit irrigation treatments DI-20 (20% of ETc) and DI-10 (10% of ETc) were applied. The daily hysteretic pattern of FD versus the environmental variable of vapor pressure deficit (VPD) was evaluated using the data of a local weather station. The assessment of fruit growth parameters showed cultivar-specific response to water stress. For instance, after performing deficit irrigation, minimum RGR in different cultivars downsized with various slopes which suggested a very different response of the cultivars to dehydration. On the other hand, the daily hysteretic pattern of FD versus VPD was detected in all the studied cultivars, and a quantitative index (height of hysteresis curves) used for explanation of hysteresis magnitude’s changed according to the deficit irrigation treatments. The results showed a significant reduction of height of hysteresis curves by irrigation treatments which were not cultivar-specific. The quantitative index for hysteresis curve magnitude’s change in the four olive cultivars of Ascolana dura, Piantone di Falerone, Arbequina and Lea can efficiently estimate the plant water response to irrigation treatment in olive orchards. However, further investigation needs to be done to implement precise irrigation systems
Continuous Monitoring of Olive Fruit Growth by Automatic Extensimeter in Response to Vapor Pressure Deficit from Pit Hardening to Harvest
Full text linkRecently, several studies on olive fruit growth have focused on circadian monitoring as an important orchard management tool. The olive fruit growth trend is described by double sigmoid model with four growth phases, where the third phase spans from the end of pit hardening to initial fruit maturation, and the last phase includes olive maturation up to fruit drop. Environmental factors play an important role in fruit growth, with vapor pressure deficit (VPD) being a keystone factor. Our experiment was designed to hourly monitor olive (Olea europaea L. cv. ‘Frantoio’) fruit transversal diameter from approximately initial pit hardening (II Phase), extension (III Phase) until harvest time (IV Phase) in the attempt to determine whether fruit growth dynamically responds to environmental variables such as diurnal VPD change in different stages of fruit development. Automatic extensimeters were applied in open field and VPD was calculated from data of our weather station. Throughout the experiment period, the circadian model of fruit growth showed two steps: shrinkage and expansion. Almost in all days of the third phase of fruit growth, daily response of transversal diameter to VPD formed complete clockwise hysteresis loops. During the fourth phase of fruit growth, with increasing fruit maturation, the complete clockwise hysteresis loop experienced some abnormality. At the fourth stage of fruit growth there were incomplete and partial clockwise hysteresis loops. We conclude that hysteresis can be employed to detect the shift between the end of the third phase (cell expansion) and the beginning of the fourth phase (fruit maturation) of fruit growth. The disappearance of the complete clockwise hysteresis loop and the substitution with incomplete, or partial clockwise hysteresis loops was observable only in the fourth stage of fruit growth. These results can be valuable for any smart fruit management of olive fruit production
Knot formation and spread along the shoot stem in 13 olive cultivars inoculated with an indigenous pathobiome of 7 species of Pseudomonas including Pseudomonas savastanoi
No full textOlive knot is a widely spread disease among olive (Olea europaea L.) trees. Pseudomonas savastanoi pv. savastanoi is recognized as the primary causative agent of the disease however, recent evidence indicated that consortia of bacteria (pathobiome), may favor its development. Several factors are involved in the host-plant relationship and affect the intensity of the symptoms. Among these the presence of wounds, or damages to the plants' tissues may affect the intensity and propagation of the disease. It remains unknown whether or not bacteria move from an infected wound to another not infected one via shoot tissues. The present investigation focused on the susceptibility to olive knot of several cultivars after inoculating artificial wounds with selected Pseudomonas species, while spreading the disease from these to wounds on the same stem, that had not been purposefully inoculated. The pathobiome for the inoculum was prepared with 7 species of Pseudomonas (including Pseudomonas savastanoi pv. savastanoi), isolated from knot samples collected from two different, heavily infected olive orchards. The inoculation was done after the manual execution of 10 horizontal wounds on the stem of potted plants of 13 olive cultivars grown in the greenhouse. Only the lowest 5 wounds were inoculated. The inoculated wounds showed a maximum percentage of knots after 187 days. All 13 cultivars showed knots yet, the cultivar with the most severe disease level to Pseudomonas savastanoi pv. savastanoi was 'Rosciola colli Esini'. The metataxonomic analysis performed on the olive knots removed after 225 days confirmed the dominance of the inoculated species Pseudomonas savastanoi in all the assayed cultivars. The not inoculated wounds did not show the knot disease likely because the bacterium's inability to transmigrate from the inoculated wounds to the non-inoculated ones
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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