6,193 research outputs found

    Recurrent deficit irrigation and fruit harvest affect tree water relations and fruitlet growth in ‘Valencia’ orange

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    Background. Partial rootzone drying is an irrigation strategy known for increasing water use efficiency without significantly affecting tree water status. ‘Valencia’ oranges have a very long development period and nearly mature fruit and new fruitlets may be present at the same time on the tree, competing for water and assimilates. Objectives. The present study investigates the effect of recurrent deficit irrigation and fruit harvest on tree water status and fruitlet growth of ‘Valencia’ orange. Methods. Forty-eight adult trees were exposed to three irrigation treatments for seven years (2007-2013): irrigation with 100% of ETc (CI), continuous deficit irrigation (DI, 50% of CI) and partial root-zone drying (PRD, 50% of CI on alternated sides of the root-zone). In spring 2014, stem water potential (Ψstem) and continuous measurements of sap flow and fruitlet growth were recorded before (May) and after (June) the harvest of mature fruit. Results. No differences in Ψstem were found among irrigation treatments, while Ψstem was lower in June than in May at midday. In both May and June, sap flow density (not sap flow per tree) was higher in DI than in CI and PRD trees suggesting more efficient water uptake/transport in the former. In May, DI and PRD fruit showed lower daily relative growth rate (RGR) than CI fruit due to a possible shortage of carbon and nutrients. After removing mature fruits, differences among irrigation treatments were canceled. Sap flow was directly related to fruit RGR at low sap flow rates, but inversely related to RGR at high sap flow rates. Conclusions. Our data show that the presence of maturing fruit does not impact the water status of ‘Valencia’ trees, while it may transiently limit fruitlet growth (by source limitation) in deficit irrigated trees

    Precision Management of Fruit Trees

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    The aim of the Special Issue “Precision Management of Fruit Trees” was to collect new insights to support the adoption of advanced, efficient, and sustainable management techniques in the fruit production sector. Indeed, this is an opportunity offered by the technological innovations adopted using new-generation sensors and implemented through precise management operations. This Special Issue contains 11 scientific articles contributing to our knowledge on the precision management of fruit trees, indicating the high activity of this sector and possibly leading to the application of new techniques/protocols to overcome global and rapidly changing environmental issues. Scalisi et al. [1], in their study, aimed to (i) determine the reliability of a portable Bluetooth colour meter for fruit colour measurements; (ii) characterise the changes in quantitative skin colour attributes in a nectarine cultivar in response to time from harvest; and (iii) determine the influence of row orientation and training system on nectarine skin colour. Overall, the device proved reliable for fruit colour detection. The results of this study highlight the potential of one of the measured parameters as a quantitative index to monitor ripening prior to harvest in nectarines. Remote sensing techniques based on images acquired from unmanned aerial vehicles (UAVs) could represent an effective tool to speed up the data acquisition process in phenotyping trials and, consequently, to reduce the time and cost of the field work. Caruso et al. [2] confirmed the ability of a UAV equipped with RGB-NIR cameras to highlight differences in geometrical and spectral canopy characteristics between eight olive cultivars planted at different planting distances in a hedgerow olive orchard. Tree densities have increased greatly in olive orchards over the last few decades. Ladux et al. [3], in their study, found that the leaf area index (LAI) of neighbouring trees modifies the light quality environment prior to a tree being directly shaded, as well as the morphological responses of olive cultivars to changes in light quality. The results suggested that cultivar differences in response to light quality may be relevant for understanding adaptation to dense orchards and identifying cultivars best suited to them. Saha et al. [4] found that monitoring plant vegetative growth can provide the basis for precise crop management. In this study, a 2D light detection and ranging (LiDAR) laser scanner, mounted on a linear conveyor, was used to acquire multi-temporal, three-dimensional (3D) data from strawberry plants. The results contributed to building up an approach for estimating plant geometrical features, particularly strawberry canopy volume profile based on LiDAR point cloud for tracking plant growth. Carella et al. [5] studied the physiological and productive behaviour of different olive cultivars grown under a high-density hedgerow system and compared their fruiting and branch architecture features to determine the possibility to use ‘Calatina’ olive trees for intensive plantings, as a local alternative to the international reference ‘Arbequina’. The study indicated that ‘Calatina’ is more efficient in terms of yield and harvesting than ‘Arbequina’. This qualifies ‘Calatina’ as a superior, yield-efficient olive cultivar suitable for intensive hedgerow plantings to be harvested with straddle or side-by-side trunk shaker machines. Sirgedaitė-Šėžienė et al. [6] used ‘Rubin’ apple trees grafted on dwarfing P60 rootstocks to determine the impact of canopy training treatments as a stress factor on metabolic response to obtain key information on how to improve physiological behaviour and the management of growth and development of apple trees. The results indicated that all applied canopy training treatments significantly increased the total phenol and total starch contents in apple tree leaves. Scalisi et al. [7] in their work aimed to derive a new fruit skin colour attribute—namely, a Colour Development Index (CDI), ranging from 0 to 1, that intuitively increases as fruit becomes redder—to assess colour development in peach and nectarine fruit skin. The study found that the CDI can serve as a standardised and objective skin colour index for peaches and nectarines. Čirjak et al. [8] summarize the automatic methods (image analysis systems, smart traps, sensors, decision support systems, etc.) used to monitor the major pest in apple production (Cydia pomonella L.) and other important apple pests and fruit flies to improve sustainable pest management under frequently changing climatic conditions. Pisciotta et al. [9] released a review underlying the opportunities offered by the recently developed table-grape soil-less cultivation systems; this is an up-to-date examination of the latest experimental and applied findings of the sector’s research activities. A special emphasis is given to the evolution of the applied technical solutions, varietal choice, and environmental conditions for the aims of table-grape soil-less cultivation. Borgogno-Mondino et al. [10] evaluated a promising alternative offered by Copernicus Sentinel 2 data (S2) to midday stem water potential for monitoring the water status of pomegranate plants and for addressing irrigation management. Despite limited ground observations, the results showed the promising capability of spectral indices (NDVI, NDRE, and NDWI) and S2 bands in estimating Ψstem readings. Boini et al. [11], in their study, used shading nets to lower irrigation requirements and make apple growing more sustainable. The encouraging results showed a comparable yield and fruit quality saving 50% of irrigation water under a classic anti-hail system compared to the control treatment

    Effects of partial rootzone drying and rootstock vigour on growth and fruit quality of 'Pink Lady' apple trees in Mediterranean environments

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    We investigated the effects of partial rootzone drying (PRD) and rootstock vigor on water relations, vegetative and productive performance of \u2018Pink Lady\u2019 apple (Malus domestica Borkh.) trees in central Sicily. In a first field trial, trees on MM.106 rootstock were subjected to: Conventional irrigation (CI), maintaining soil moisture above 80% of field capacity; PRD irrigation, where only one alternated side of the rootzone received 50% of the CI irrigation water; and continuous deficit irrigation (DI), where 50% of the CI water was equally applied to both sides of the rootzone. In a second trial, trees on M.9 or MM.106 were subjected to CI and PRD irrigation. PRD reduced stomatal conductance (gs) more consistently in trees on MM.106 than in trees on M.9, but maintained relative water content (RWC) to the levels of CI. DI induced greater gs reductions than PRD and lower RWC than CI and PRD. Rootstock vigor did not influence plant response to irrigation strategy. PRD induced some reduction in fruit number but no change in yields and fruit quality compared to CI, whereas DI reduced fruit size and marketable yields. Significant reductions in shoot and leaf growth were induced by DI, whereas only leaf growth was affected by PRD. Our observations indicate that responses induced by PRD are due to a combination of the amount and way of applying water, and not just to reductions in irrigation volumes, suggesting a possible use of PRD for increasing apple water use efficiency in Mediterranean environments

    Fruit growth stage transitions in two mango cultivars grown in a mediterranean environment

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    Studying mango (Mangifera indica L.) fruit development represents one of the most important aspects for the precise orchard management under non‐native environmental conditions. In this work, precision fruit gauges were used to investigate important eco‐physiological aspects of fruit growth in two mango cultivars, Keitt (late ripening) and Tommy Atkins (early‐mid ripening). Fruit absolute growth rate (AGR, mm day−1 ), daily diameter fluctuation (ΔD, mm), and a development index given by their ratio (AGR/ΔD) were monitored to identify the prevalent mechanism (cell division, cell expansion, ripening) involved in fruit development in three (‘Tommy Atkins’) or four (‘Keitt’) different periods during growth. In ‘Keitt’, cell division prevailed over cell expansion from 58 to 64 days after full bloom (DAFB), while the opposite occurred from 74 to 85 DAFB. Starting at 100 DAFB, internal changes prevailed over fruit growth, indicating the beginning of the ripening stage. In Tommy Atkins (an early ripening cultivar), no significant differences in AGR/ΔD was found among monitoring periods, indicating that both cell division and expansion coexisted at gradually decreasing rates until fruit harvest. To evaluate the effect of microclimate on fruit growth the relationship between vapor pressure deficit (VPD) and ΔD was also studied. In ‘Keitt’, VPD was the main driving force determining fruit diameter fluctuations. In ‘Tommy Atkins’, the lack of relationship between VPD and ΔD suggest a hydric isolation of the fruit due to the disruption of xylem and stomatal flows starting at 65 DAFB. Further studies are needed to confirm this hypothesis

    Serum Anti-Thyroglobulin Autoantibodies Are Specific in Predicting the Presence of Papillary-like Nuclear Features and Lymphocytic Infiltrate in the Thyroid Gland

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    (1) Background: Previous studies have reported a correlation between serum anti-Thyroglobulin-antibodies (TgAb) and papillary thyroid carcinoma. The aim of our study was to evaluate whether serum TgAb and anti-thyroid-peroxidase antibody (TPO) positivity was also related to pre-neoplastic histological changes such as papillary-like nuclear features (PLNF) and with the presence of lymphocytic infiltrate (LI) in thyroid surgical specimens. (2) Methods: The study was retrospectively carried out on 70 consecutively recruited patients who underwent thyroidectomy for benign process and whose TgAb and TPOAb values were retrieved from clinical records. Histological sections of thyroid surgical samples were revised, looking for PLNF and lymphocytic infiltrate. HBME1 expression was assessed by immunohistochemistry. (3) Results: Our results showed a significant association between TgAb, PLNF, and lymphocytic infiltrate. The presence of TgAb was highly specific, but less sensitive, in predicting the presence of PLNF (sensitivity = 0.6, specificity = 0.9; positive predictive value (PPV) = 0.88; negative predictive value (NPV) = 0.63). TgAb positivity showed a good association with the presence of lymphocytic infiltrate (sensitivity = 0.62, specificity = 0.9; PPV = 0.88 and NPV = 0.68). HBME1 immunoreactivity was observed in the colloid of follicles showing PLNF and/or closely associated with LI. (4) Conclusions: The presence of PLNF and LI is associated with serum TgAb positivity. The presence of TgAb and of LI could be triggered by an altered thyroglobulin contained in the HBME1-positive colloid, and could be a first defense mechanism against PLNF that probably represent early dysplastic changes in thyrocytes

    Milk Products in Bread Making

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    The topic was the usage of milk in bread making. Initial investigations in bread making using milk were aimed at learning how to prepare milk best suited for bread making and finding the proper quantities for optimum results. The convenience, economy, and uniformity of dry milk solids greatly increased their usage by bakers. These advantages have been further augmented by research and experimentation by the dry milk producers, which have resulted in a product which would appreciably improve bread quality. Milk may be altered both in physical and chemical properties by heating. The article goes on to give more information on milk usage in baking

    Autism spectrum disorder in Italy: demand for an integrated epidemiological surveillance system.

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    Autism spectrum disorder (ASD) is a complex neurodevelopmental syndrome of emerging public health concern, according to a documented significant increase of diagnosed cases of ASD in Europe and USA. In Italy, actually, it is not possible to estimate at national level a reliable ASD occurrence by using existing health and scholastic data flows. The lack of information has implications on social and healthcare services dedicated to subjects affected by ADS. The database of the Italian institute in charge of social and security assistance was accessed at the provincial level to investigate the ASD cases occurred in the Palermo province. The official reports of all subjects visited in 2013 by INPS physicians were analyzed by using an automatic software and diagnosis consistent with ASD were ex- tracted and flagged. Our findings support the choice of alternative use of INPS administrative database in order to define a reliable ASD occurrence estimate as first step to develop an integrated epidemiological surveillance system on AS

    Monitoraggio in tempo reale dello stress idrico del pesco

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    La frutticoltura odierna è sempre più caratterizzata dall’utilizzo di nuove tecnologie che si basano sull’utilizzo di molteplici sensori. Una delle grandi sfide della Smart Agriculture (agricoltura intelligente) è quella di integrare le informazioni provenienti da sensori remoti, prossimali e a contatto in modelli informativi in grado di sostenere gli agricoltori, in modo tale da determinare un sostanziale beneficio economico per le aziende. La complessità delle informazioni ottenute scoraggia l’integrazione di dati apparentemente molto diversi, ma allo stesso tempo apre le porte a nuovi modelli d’impresa. In questo lavoro vengono messi in risalto alcuni vantaggi e difficoltà dell’utilizzo congiunto di sensori su foglie e frutti di nettarine

    A dipole band in 124 Xe

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    High-spin states in 124Xe were populated by means of the 110Pd(18O,4n) reaction. In-beam γ rays were measured using the GASP spectrometer. A dipole band, similar to those previously found in other nuclei of this mass region, was identified in 124Xe
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