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Seasonal changes of mineral nutrients in olive leaves during the alternate-bearing cycle

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Abstract

Samples of olive (Olea europaea L.) leaves developed in 1993, 1994 or 1995 were collected separately from non-irrigated, mature trees at monthly intervals during 1994 (`off' year) and 1995 (`on' year) to determine leaf-nutrient concentration and nutrient content per leaf. N, P, K and Mg contents were affected by crop load, showing lower values following the `on' year. No effect of crop load was observed on micronutrient accumulation in leaves, probably because of the lower requirements for these elements of the olive fruit. Leaf age also influenced leaf-nutrient concentration and nutrient content. Leaf N, P, K, Zn and B concentrations were higher in younger leaves, whereas leaf Ca, Mg, Mn, Cu and Fe concentrations were higher in older leaves. Ca, Mg, Mn, Cu and Fe content per leaf were also higher in older leaves. There was little or no difference in P, K, Zn and B content among leaves of different ages. N content per leaf was higher in older leaves during the growing period of the `off' year. Seasonal mineral fluctuations curves for different leaf mineral nutrients were developed which could be used in the interpretation of leaf analysis.

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... Each composite leaf sample consisted of c. 180 leaves sampled from three neighbouring trees. In order to avoid variation in nutrient composition of leaves due to physiological age of tissues, only fully developed leaves from the central part of one-year-old shoots were sampled (Fernández-Escobar et al. 1999;Perica 2001;Sibbett and Ferguson 2002). Furthermore, to reduce light and position effects, special care was exercised in collecting leaves randomly from positions all around each tree at the height of 1.5-2 m (Wolf 1982;Perica 2001). ...
... Copper and Mo (except in leaves from olives grown in Lithosol) and Fe (except in leaves from Rendzina-grown olives) concentrations were also above the sufficient values (Marschner 2012). In contrast, Cu and Mo in leaves from olives grown in Lithosol, Fe in leaves from Rendzina-grown olives, and K, Mg, P, Mn and Zn in all leaves were somewhat lower than the sufficiency levels reported by Marschner (2012), but they were higher than the minimal values required for adequate olive growth (Therios 2009), or at least in case of Mn higher than the deficiency levels reported by Fernández-Escobar et al. (1999) and Therios (2009) (Table 8). The decreased micronutrient concentrations in the available fraction in topsoil and leaves from Lithosol could also be due to leaching because these groves are situated on steep slopes (Husnjak 2014). ...
... Range of leaf nutrient concentrations in Oleaceae family (Watanabe et al. 2007) and olive leaves found in the literature. For comparison, the average shoot nutrient concentrations sufficient for adequate plant growth (Marschner 2012) including olives (Reuter and Robinson 1997;Therios 2009), the olive deficiency thresholds by Fernández-Escobar et al. (1999), and the values indicating relative deficiency of nutrients in olive leaves (Therios 2009) and Robinson 1997; Therios 2009). A study conducted by Linder (1995) had the aim of finding the optimum nutrient concentrations in Norway spruce. ...
Article
An important part of agriculture in the European Mediterranean area is olive (Olea europaea L.) production. Characterising the relationships between properties of different soils where olive is grown and nutrient status in olive leaves can enhance our understanding of soil-plant interactions. Three different soils (Terra rossa, Rendzina, Lithosol) were characterized for their physical and chemical characteristics; plant-available nutrients were extracted with ammonium nitrate. Soils, soil extracts and leaf digests were analysed for nutrients and for nitrogen in soils and leaf. A redundancy analysis (RDA) was applied to elucidate relationships between soil properties and leaf nutrients. As revealed by RDA, leaf concentrations of Mg, K, Ca and micronutrients were explained by available Mg, total carbonates and soil organic carbon in topsoil. Leaf concentration of Na was associated with total Na in topsoil. Copper and Mo deficiencies were detected in plants grown in Lithosol, and Mg, P, Mn and Zn deficiencies were noted in all plants. Through appropriate agronomic techniques, Lithosols can be used for olive groves, but they have significant limitation regarding nutrient availability. Our results support the relevance of using soil nutrient variability to provide a basis for optimisation of measures for olive groves.
... Annual fluctuation in nutrients which may affect the alternate bearing phenomenon in different fruit trees [15], and their accumulation varied with tree vegetative growth under different weather conditions in olive [16]. Therefore, intensive care is needed for selection of soil and leaf samples during nutritional status measurement [17,18]. It is strongly recommended the construction of balance sheet regarding nutrient for an olive orchard by keeping in mind the plant population per hectare, nutrients depletion round the year at different stages and depletion of nutrient level by runoff or through leaching, different intensities of pruning and cover crops. ...
... Our results were found similar with the findings of Fahmy and Nasrallah, [41] who found that the leaf phosphorus content in olive vary with the stages and between the growing years but contradiction was found with the statement that leaf phosphorous level increased with the time. However, our results in line with the findings of Fernandez-Escobar et al., [17] who found permanently the lowest value in fruit development stages and the highest value after harvest. Phosphorus is the part of structural components, and also active play important role in physiological and energy processes [42]. ...
... These trends were in accordance with the findings of Boulal et al., [44] who suggested, potassium application in the later stages of crop growth and fruit ripening because at this stage need for potassium is generally high in olive plants. It may vary from year to year in relation with crop load with similar suggestions by Fernandez-Escobar [17]. Our results are in agreement with the finding of other researchers who reported that leaf potassium level decreased with the increase of development of fruit and season, which suggested the remobilization of K content from leaf to fruit parts [44,45]. ...
Article
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Olive is grown in semi-arid climatic conditions; however, little is known about mineral changes in olive plant and nutrient requirements during the production period. Hence, the current study was conducted under Pothwar agro-climatic conditions in order to select appropriate stage of macronutrients (N, P, K) application in relation to soil and leaf nutritional status during 2017 and 2018 growing seasons. Soil and leaf analysis were performed at four different phenological stages (i.e. flowering, fruit setting, fruit enlargement and fruit maturity stages). The results revealed that the assessed macronutrient in leaf and soil varied significantly among varieties, phenological stages and growing year. The results revealed also that nitrogen level was found to decrease from fruit set (1.56%) to fruit enlargement stage (1.47%). Leaf and soil N, P and K contents were found higher before the flowering (stage 1) and depleted after fruit harvesting (stage 4), regardless of olive varieties. However, high yielding varieties showed lower nutrients after fruit harvesting (stage 4). Therefore, N content in leaf and soil gradually decreased during fruit growth and development. Whereas, K content in leaf and soil sharply declined from fruit maturity to fruit ripening stage. Overall, the trend of nutrient depletion showed that plants need phosphorus for fruit setting, nitrogen before and after fruit setting, and potash after pit hardening or at oil accumulation stages.
... Concentration of nitrogen in leaf in ecological conditions of Ulcinjsko polje is above the concentration that Picholine variety had in conditions of Istria (Miljkovic, 2006) where, contrary to our results and observations of Ulger et al. (2004), the concentration increased toward the end of the period observed, from 1.49 to 1.80%. In the same conditions of Istria Leccino variety had nitrogen concentration from 2 to 2.4%, and in Ulcinjsko polje other varieties had much lower concentrations (Lazovic, 2001) measured in August but above the satisfactory limit of 1.5% given by Escobar et al. (1999), while Žutica in Bar had about 2% N in leaf (Lazovic, 2001). High concentrations were also recorded in different Italian olive varieties, from 1.88 do 2.25% N (Tittarelli i sar., 2006), as well as in Greek varieties and in olive orchards measured at the beginning of March, from 1.90 do 2.10% (Vemmos i sar., 2006). ...
... Potassium concentration increased at the beginning of the measuring period by 0.4%, slightly decreased during further period of vegetation reaching 1.32% at the end of measuring which was above the concentration for this variety in conditions of Istria (Miljkovic, 2006), as well as in various varieties in Ulcinjsko polje (Lazovic, 2001), and much above the data given for different Italian and Greek olive varieties and orchards (Tittarelli et al., 2006;Dimasi et al., 1997;Vemmos et al., 2006). Similar decreasing tendency of K in leaf was recorded by Escobar et al. (1999) but with concentrations lower than of the satisfactory limit in 'on' and 'off' years. ...
... Graph. 3. Dynamics of N, K and Ca concentration in leaf of Picholine variety picholine olive variety in conditions of Ulcinjsko polje Permanent slight increment from the beginning to the end of measuring was noted in Ca concentration, 0.91 to 1.22 %, which is in accordance with literature data on permanent increment of this element (Miljkovic, 2006, Escobar et al., 1999. Concentration of Ca in our experiment was lower than the observations for different Italian and Greek olive varieties (Tittarelli et al., 2006;Dimasi et al., 1997;Vemmos et al., 2006), which can be a result of soil properties. ...
Article
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In conditions of Ulcinjsko polje, during the period 1987-1991, growth intensity of one-year old olive shoots and fruit growth in Picholine variety were investigated. Related to that, the dynamics of mineral nutrition (N, P, K, Ca and Mg) was followed in leaves and fruits in the period from middle of July to the middle of October. Results showed that nutrient status during vegetation period was within optimal values for olive. Decreasing dynamics during vegetative period was in N (from 2.22% to 1.67%). Slight increasing dynamic was showed in K (1.15% to 1.32%), Ca (0.91% to 1.22%) and Mg (0.17% to 0.21%), while P had a relatively stable content in olive leaves (0.19%). Nutrient status in the fruit showed different tendencies. Decreasing dynamics showed N (0.81 to 0.59%), Ca (260 to 229 ppm) and Mg (228 to 191 ppm). Slight increment showed P (0.13 do 015%) and K (1.44 do 1.51 %). SAŽETAK U uvjetima Ulcinjskog polja u razdoblju od 1987. do 1991. istraživani su intezotet rasta jednogodišnjih izdanaka masline I rast ploda sorte Picholine. U vezi s time praćena je dinamika (N,P,K,Ca I Mg) u lišću I plodovima u razdoblju od sredine srpnja do sredine listopada. Rezultati su pokazali da je stanje hraniva u vrijeme vegetacije bilo u rasponu optimalnih vrijednosti za maslinu. Dinamika opadanja u razdoblju vegetacije bila je za N (od 2,22% do 1,33%). Dinamika neznatnog povećanja pokazala se u K (1,15% do 1,32%), Ca (0,91% do 1,33%) I Mg (0,17% do 0,21%) dok je P imao relativno stabilan sadržaj u lišću masline (0,19%). Stanje hraniva u plodu pokazalo je različite tendencije. Dinamiku opadanja pokazali su N (0,82 do 0,59%), Ca (260 do 229 ppm) I Mg (228 do 191 ppm). Lagano povećanje pokazali su P (0,13 do 0,15%) i K (1,44 do 1,51%).
... For K content, Toplu et al. (2009) [23] obtained concentrations in olive leaves from Manzanilla in conventional system between 9.90 and 8.90 g/kg, which is very similar to those obtained in this study. While it is true that a lack of irrigation inhibits K absorption and reduces its availability in soils, which could be the case in these rainfed plots, all the leaves analyzed were above the deficiency threshold of 4 g/kg [9,24]. In addition, this draws attention to the highest value of Manzanilla collected in harvest season, which could be related to the greater amount of rainfall compared to the pruning season (Figure 1b). ...
... The Mn concentration, in all cases, was above the deficiency level (20 mg/kg). B content can be considered deficient according to Beutel et al. (1978) [25], who considered B deficient when the concentration is under 14 mg/kg, while Fernández-Escobar et al. (1999) [24] proposed 33 mg/kg as a limit. Although in our study B concentrations in olive leaves were lower than 14 mg/kg, not a single visible B deficiency symptom, such as apical chlorosis or rosette-arranged new leaves [24], was observed. ...
... B content can be considered deficient according to Beutel et al. (1978) [25], who considered B deficient when the concentration is under 14 mg/kg, while Fernández-Escobar et al. (1999) [24] proposed 33 mg/kg as a limit. Although in our study B concentrations in olive leaves were lower than 14 mg/kg, not a single visible B deficiency symptom, such as apical chlorosis or rosette-arranged new leaves [24], was observed. For this reason, all the B concentrations determined in this study could be characterized as low, but not necessarily deficient. ...
Article
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Olive leaves are still considered waste in the oil industry; however, the leaves have a content of oleuropein and other bioactive compounds that gives them great potential to be transformed into by-products. The most appropriate moment along an agronomic cycle (November 2019 to October 2020) has been evaluated to take advantage of this potential of the olive leaves varieties of Picual, Cornicabra and Manzanilla. In addition, factors that affect the content of phenolic compounds such as absolute maximum and minimum temperatures, relative humidity, sunshine hours, rainfall, differential of temperatures and mineral nutrition have been studied. The results show that the pruning season was the best time to take advantage of the olive leaf due to its high oleuropein content, especially in Picual and Manzanilla. The variety was the factor that most affected all the phenolic compounds studied, while the absolute minimum temperature factor notably affected verbascoside. Particular mineral nutrients, such as Mg and Fe, turned out to be most useful for differentiating locations. The content of verbascoside and hydroxytyrosol was also affected by agronomic conditions (location/conventional or ecological).
... Leaf nutrient analysis is considered the best method for diagnosing the nutritional status of a tree and is an important tool for determining its fertilizer needs (Jones 1985). The tracking of seasonal variations in leaf nutrient contents is necessary in order to understand the physiological aspects of olive nutrition, and is also helpful in the interpretation of leaf analysis (Fernandez-Escobar, Moreno, and Garcia-creus 1999). In the northern hemisphere, flower bud induction is manifested by July, around the time of endocarp sclerification (Fernandez-Escobar et al. 1992). ...
... Shortly after flowering, massive abscission of flowers and fruits occurs (Rallo and Fernandez-Escobar 1985). The remaining fruits usually persist on the tree until harvest, which takes place during the fall and early winter (Fernandez-Escobar, Moreno, and Garcia-creus 1999). These authors found that leaf age influenced the leaf nutrient content; the leaf nitrogen, phosphorus and potassium contents were higher in young leaves. ...
... This is where the olive need for potassium is generally high. The high accumulation of potassium in the olive leaves after an "off" year and its rapid decline after March of "on year" suggests large potassium demand by the reproductive structures of the olive tree (Fernandez-Escobar, Moreno, and Garcia-creus 1999). Other researchers (Ryugo 1988;Shear and Faust 1980) reported that the leaf potassium concentration declines in most tree crops as the season progresses. ...
Article
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The study aims to track the dynamics of the olive leaf nitrogen (N), phosphorus (P) and potassium (K) for five olive varieties under drip irrigation in farmer's fields in central Morocco. Leaf sampling was done every month from May 2014 to April 2015. Leaf macronutrients contents showed variation over time. Olive leaves have maintained the same N content throughout the study period indicating a continuing olive uptake of nitrogen. Higher leaf P absorption was observed during flowering and fruit magnification periods indicating the important P needs of olive during these periods. Olive leaf K levels were higher from September to December indicating the high K needs of olive. No variety effect was revealed on the leaf N, P and K contents. Very highly significant differences were found between the leaf N and K levels measured at different sampling periods. The leaf P concentration was statistically equal in all measuring periods.
... According to Therios [17], olive leaves with K concentration below 0.5% are relatively deficient. Only leaves collected from Loc. 1 had K concentration below this threshold level, but low K values are common in leaves of dry-cultivated olive trees [3] and the olive orchards in Loc. 1 were not irrigated. Ca concentration in olive leaves of all studied locations were above 1%, which is the sufficiency threshold level. ...
... below the sufficiency threshold level of 0.1% to all locations. Mg concentration in olive leaves from locations 1 and 2 were below the sufficiency threshold level of 0.1% compared to olive leaves from locations 3 and 4. Mn concentration in olive leaves from locations 1, 2 and 4 was below the sufficiency threshold level of 20 mg kg -1 and only Mn concentration of leaves from Loc. 3 was slightly above this level [3]. Fe concentration in olive leaves was always sufficient (above 50 mg kg -1 ) [17]. ...
... Zn concentration in olive leaves was also almost always deficient (sufficiency threshold level at 10 mg kg -1 ). In addition, Cu concentration was also deficient in the three locations (sufficiency threshold level at 5 mg kg -1 ), except of the leaves from Loc. 3, where Cu fungicides were used regularly [3,17]. In conclusion for the main necessary nutrients in our experimental olive farms, K, Ca and partly Mg were sufficient in olive leaves and P, Mn, Fe, Zn and Cu were usually deficient. ...
Article
In the Mediterranean region, summer is characterized by semi-arid conditions with rare rain events. At the same time, many sources of particulate matter emissions result in foliar dust accumulation. We investigated the effect of unpaved road dust, quarry dust and cement kiln dust foliar accumulation on leaf characteristics of apple, peach and olive trees and the effect of cement kiln dust foliar accumulation on the inorganic element composition of olive tree leaves. Dust deposition on leaf surfaces increased chlorophyll content, mainly chlorophyll b and decreased chla/chlb ratio, changes associated with shading. But dust deposition also altered leaf morphology, increasing specific leaf matter and percent dry mass, in a way clearly showing that dusts affect more leaf mechanisms besides shading. The alkaline nature and chemical composition of cement kiln dust seemed to alter olive leaf nutrition by decreasing useful trace element and increasing Cd concentrations around the cement industry.
... Finally, leaves were placed in paper bags and were taken to the laboratory following the protocol established by the Agrifood Laboratory of the Junta de Extremadura (Cáceres, Spain). The critical and sufficiency threshold of LNC of each olive tree were estimated at 1.4% and 1.5%, respectively (Barranco et al. 1997;Fernández-Escobar et al. 1999). ...
... N status of sampled olive trees was deficient considering a critical and sufficiency threshold of LNC of 1.4% and 1.5%, respectively (Barranco et al. 1997;Fernández-Escobar et al. 1999). Fernández-Escobar et al. (2009) studied the long-term effect of N fertilization on olive trees. ...
Article
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Olive orchard is one of the main crops in the Mediterranean basin and, particularly, in Spain, with 56% of European production. In semi-arid regions, nitrogen (N) is the main limiting factor of olive trees after water and its quantification is essential to carry out accurate fertilization planning. In the present study, N status of an olive orchard located in Carmonita (southwest Spain) was analysed using hyperspectral data. Reflectance data were recorded with a high precision spectro-radiometer through the full spectrum (350–2500 nm). Different vegetation indices (VI), combining two or three wavelengths, and partial least squares regression (PLSR) models were developed, and the prediction capabilities were compared. Different pre-processing (smoothing, SM; standard normal variate, SNV; first and second derivative) were applied to analyse the influence of the noise generated by the spectro-radiometer measurements when computing the determination coefficient between leaf N content (LNC) and spectra data. Results showed that second derivative combined with SNV pre-processing produced the best determination coefficients. The wavelengths most sensitive to N variation used to perform VI were selected from the visible and the short-wave infrared spectrum regions, which relate to chlorophyll a + b and N absorption features. DCNI and TCARI showed the best fittings for the LNC prediction (R2 = 0.72, R2cv = 0.71; and R2 = 0.64, R2cv = 0.63, respectively). PLSR models yielded higher accuracy than the models based on VI (R2 = 0.98, R2cv = 0.56), although the large difference between calibration and cross-validation showed more uncertainty in the PLSR models.
... The Highest levels of N have been found for the treatment F3 in July and September, which may be explained by the hypothesis of the presence of less fruits in the trees of this treatment according to the production recorded (data not shown). In a previous study, a drop of N has also been observed since June to reach a minimum in August (Fern andez-Escobar et al., 1999), which is similar to our results. P and K have been accumulated in the leaves after foliar application although they were not present in the products applied. ...
... The results also showed an accumulation, with time, of the element Ca in leaves of the olive trees. Similar results were found in the study of Fern andez-Escobar et al. (1999). This tendency is typical for Ca as it was mentioned by Ryugo (1988) since this element is not re-translocated to the sink organs (fruits or roots). ...
Article
Fertilization practices in Tunisian olive growing are widely used in order to improve the yields and the mineral status of the trees grown under rain-fed conditions (low received rainfall). The aim of this study is to assess the effect of foliar fertilization on mineral composition and primary metabolites (soluble sugars) in leaves and roots of cultivar Chemlali. A nitrogen based fertilizer and two biostimulants were sprayed separately in different seasons and the treatments were the following: F1 (nitrogen based fertilizer), F2 (biostimulant rich in boron), F3 (combination of F1 and F2), F4 (biostimulant with a calcium base) and F5 (Combination of F1, F2 and F4). Untreated trees (no foliar fertilization) were used as control (C). Leaf and root samples of treatments F1, F2 and F3 were collected at different phenological stages while samples of F4 and F5 were collected at fruit growth. Mineral content and carbohydrate composition were carried out in all the samples. Results showed that foliar fertilization generally improved the mineral profile of leaves for both macro and micronutrients. Macronutrient concentrations were more important in leaves than in roots while the micronutrients were the highest in roots. Concerning carbohydrates status, the most abundantly soluble sugar in leaves and roots was mannitol followed by glucose. Differences in carbohydrates concentration were observed in leaves through the season and the treatments. The combined treatment F3 induced a positive effect on the pool of soluble sugars in leaves at flowering. Then, both mannitol and glucose decreased in July compared to the levels in May, a fact which can be explained by the high carbohydrate demand for fruit growth during this period. Roots accumulated lower contents of carbohydrates. The ratios macronutrients/total carbohydrates and micronutrients/total carbohydrates were higher in the roots than in the leaves. All these results showed the impact of foliar fertilization on the mineral and carbohydrate status and highlighted a relationship between them for different organs of the olive tree cultivated under rain-fed conditions.
... In fact, in-season differences in leaf K concentrations are largely species-dependent. For instance, olive leaves have a tendency to increase K concentrations from the dormant season to mid-summer and then further leaf aging results in decreasing K concentrations (Fernandez-Escobar et al. 1999;Chatzisavvidis et al. 2005). The present leaf K concentrations were similar to the findings of Singh et al. (2016) for grapefruits. ...
... In agreement with the present findings, leaf Fe concentration of oranges peaked in early summer and then followed by subsequent decreases (Sheng et al. 2009). However, Fernandez-Escobar et al. (1999) and Chatzistathis et al. (2010) reported that leaf Fe concentration of olives fluctuated throughout the season. The Fe uptake and translocation in plants are affected by several factors including extreme soil temperatures, waterlogging or drought, excessive soil P and Ca concentrations, high carbonate content and pH (Kacar and Katkat 2007). ...
Article
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The characteristics of rootstock have impacts scion’s nutritional status, resistance to environmental stresses and adaptation to a specific region. Thus the performance of a cultivar is largely dependent on the rootstock-scion interactions. In this study, seasonal variations in mineral nutrients of ‘Nova’ and ‘Robinson’ mandarin cultivars budded on different citrus rootstocks were investigated under Dörtyol-Hatay (Turkey) ecological conditions. Nitrogen (N), phosphorus (P) and potassium (K) contents of the leaves exhibited slightly similar trends with each other. In general, these nutrients decreased from January to March-April and increased in the subsequent growing season until mid- and late summer, then decreased again until December. Similar trends were also observed in calcium (Ca) and magnesium (Mg) concentrations of leaves. Leaf Ca and Mg concentrations decreased from January to March, then increased during fruit development until July-August and decreased again during autumn and winter. Also, micro elements such as iron (Fe), zinc (Zn), manganese (Mn) and copper (Cu) increased from January to May–June and then gradually decreases began during the growing season until December. Throughout the entire growing season, mean macro nutrients such as N, K and Ca concentrations ranged from 1.89% (‘Nova’/Carrizo citrange) to 2.02% (‘Robinson’/Carrizo citrange), from 1.10% (‘Robinson’/Carrizo citrange) to 1.39% (‘Nova’/Carrizo citrange) and from 2.62% (‘Nova’ /sour orange) to 3.48% (‘Robinson’/Troyer citrange), respectively. Phosphorus and Mg concentrations showed slightly similar trends and varied between 0.14–0.16% and between 0.31–0.39%, respectively. The ranges of mean micro nutrients such as Fe, Zn, Mn and Cu concentrations were between 65.3 and 75.4 mg kg⁻¹, 33.7 and 39.6 mg kg⁻¹, 64.1 and 70.6 mg kg⁻¹, and 10.5 and 11.4 mg kg⁻¹, respectively. It can be concluded that rootstock-scion relations can cause considerable differences in seasonal nutrition of mandarin cultivars.
... Leaf P concentration was higher in younger leaves, decreased with leaf maturation and reached 1.63 mg g -1 on the last sampling date ( Table 2). The seasonal changes found in leaf P concentration were generally in agreement with those reported for other fruit tree species such as walnuts (6) and olives (9), in which leaf P concentration decreased throughout the growing season. The application of chemical thinners had no effect on leaf P compared with non-treated trees in the control. ...
... Leaf Ca was significantly affected by sampling time, but not by chemical thinning or the interaction between the two ( Table 1). The concentration of Ca in leaves showed a minimum value at 45 DAFB and increased significantly until the last sampling time (Table 2), a tendency which is typical for this element (9,24). The increase in leaf Ca concentrations throughout the season can be explained by Ca immobility in plant tissues and its lack of redistribution to other plant organs (15). ...
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The purpose of this study was to elucidate the effects of chemical thinning on seasonal variations of leaf and fruit mineral compositions of 'Soltani' apple trees. Treatments, including unthinned control, naphthalene acetic acid (NAA) at 5 and 10 mg L-1 , naphthaeneacetamide (NAD) at 25 and 50 mg L-1 , benzyladenine (BA) at 50 and 100 mg L-1 and carbaryl at 500 and 1000 mg L-1 were applied when fruit diameters were about 8 to10 mm. The results showed that leaf nitrogen (N), phosphorus (P) and potassium (K) concentrations decreased, whereas calcium (Ca) and magnesium (Mg) increased during the season. Fruit mineral concentration changed with the age of the fruits. All nutrients decreased with fruit maturation. Most chemical thinners affected leaf concentrations of N and K but not P, Ca and Mg. Chemical thinning increased the fruits' P, K and Mg concentrations. It is concluded that fruit chemical thinning may affect the accumulation of some nutrients, especially P and K in apple fruits and could improve fruit quality as well.
... It was suggested earlier that K is important for the regulation of plant water status [30], meaning its deficiency observed at CP3 possibly increased the response of the plant to possible water stress and induced the intensification of biophenol metabolism. Calcium exhibited a similar pattern at CP3 in March, which coincided to that observed by Fernández-Escobar, Moreno and Garcia-Creus [55] and Stateras and Moustakas [49]. ...
... The study in question [49] was conducted with the leaves of Kothreiki olive cultivar grown in Eastern Greece, an area characterized by the typical Mediterranean climate very similar to that in Pag and Zadar locations in this work. Similar was observed by Fernández-Escobar et al. [55] in Southern Córdoba province in Spain. A decrease observed by the end of winter at CP3 was possibly partly a consequence of weaker P uptake under lower air and soil temperatures, as indicated previously [56]. ...
Article
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The interactive effects of cultivar, collecting period, and geographical location on the content and composition of biophenols and macro and micronutrients in olive (Olea europaea L.) leaf were investigated. Leaves of six cultivars were collected at three periods in two locations in Croatia. The leaves of Istarska bjelica cultivar had the greatest biophenol (oleuropein) potential, especially those sampled in January and in March at the location of Pag. All the cultivars yielded leaves with the highest concentration of biophenols in March, which coincided with the pruning period. Except for high oleuropein concentration in Istarska bjelica, flavonoids were found to be most useful for differentiating olive leaves according to cultivar. Verbascoside turned out to be the most potent differentiator of collecting periods, while phosphorus and zinc turned out to be most useful for differentiating locations. Despite different agroecological conditions at the two locations, cultivar exhibited a significant effect on olive leaf nutrient composition, which was certainly causally related to that of the biophenols. The results obtained showed that it is possible to plan more well-timed and efficient exploitation of biophenols from olive leaf based on the knowledge about the interactive effects of the three studied factors.
... The rise in yield efficiency as well as in fruit characteristics by nano-B, especially with nano-B 2 treatment, are rational reasons for the decrease in macro elements in the leaves due to their nutritional consumption. The strong consumption of N, P and K could be regarded in relation to the floral developmental process, fruit production, growth and a high amount of crop load has been reported in olive tree previously (Connell et al., 2000;Fernandez-Escobar et al., 1999). Regardless of the high fruit set and yield in trees, B and Fe content of leaves in trees treated with nano-B 2 were high in August and October. ...
... The improvement of nutrient status by foliar application of boron nano-fertilizer has been postulated in pomegranate trees (Davarpanah et al., 2016). Also, the influence of crop load on micronutrient accumulation in leaves is reportedly imperceptible, probably because of the lower requirements for these elements (Fernandez-Escobar et al., 1999). ...
Article
A wide range of Boron-containing compounds is available in the world market, with different formulations and efficiencies. Among these compounds, nano-chelated products are becoming popular, although there is only limited information on their efficiency. Thus, this study considers the effects of boron nano-chelated fertilizer and boric acid foliar sprays on fruit and oil yield in olive cv. ‘Zard’. Their quality attributes were studied during the growing seasons of 2017 and 2018. Fertilizers were used at the concentration of 105 (B1) and 158.8 (B2) mg boric acid, 200 (nano-B1) and 300 (nano-B2) mg nano-chelated boron, corresponding to 180 mg (B1 and nano-B1) and 270 mg (B2 and nano-B2) pure boron per liter. Spraying with water was considered as the control (B0). Fruit characteristics were affected mainly by nano treatments and fruit yield efficiency increased by the use of nano-B2. In spite of the heavy fruit weight and yield, the nano-B2 caused a lower amount of oil accumulation in fruits. A high oil percentage was achieved by the treatment of boron (B2) which resulted in a low crop load. Traits such as oil yield, free fatty acids, antioxidant activity and total phenol content were improved by the application of nano-B2 fertilizer. Fatty acid composition was affected by B1 foliar application. Generally, the data obtained from this study showed that nano-B2 could provide beneficial effects on the growth, fruit and oil yield rather than on oil percentage. The main fatty acid composition was influenced more by boric acid treatments.
... The average Zn concentration in dry olive leaf matter in Mediterranean countries is 23.5 mg/kg leaf DW (Bouat 1968, cited in Lasram andTnani 1992) which was greater than in the control treatment but close to the Zn-ZA treatment (22 mg/kg leaf DW) ( Table 2). In general, the results of this study (11-22 mg/kg leaf DW) ( Table 2) correspond to the amount of Zn reported by various authors (Chatzistathis, Therios, and Alifragis 2009;Chatzistathis et al. 2010;El-Fouly et al. 2007;Fernandez-Escobar, Moreno, and Garcia-Creus 1999;Soyergin, Genc, and Fidan 2002). Despite the fact that this experiment was conducted under alkaline soil conditions in which the availability of Zn is greatly reduced (Imas 2000), the amount of Zn, regardless of the fertilization treatment, did not fall below the limit of 10 mg/kg leaf DW which is the deficiency level in olives (Connor and Fereres 2005;Freeman, Uriu, and Hartmann 2005;Therios 2009). ...
... This is in consistent with the results of Ming and Allen (2001) who reported an increased efficiency of P and/or K mineral fertilizers coinciding with the use of zeolites. In general, the studied K concentration levels found in the plants (16.6-19.7 g/kg leaf DW) ( Table 6) are greater than those found in most of the literature references (Chatzistathis, Therios, and Alifragis 2009;Chatzistathis et al. 2010;El-Fouly et al. 2007;Fernandez-Escobar, Moreno, and Garcia-Creus 1999;Miljković 2006;Perica 1996;Rodrigues et al. 2012;Soyergin, Genc, and Fidan 2002;Tekaya et al. 2016;Toplu, Uygor, and Yildiz 2009;Ulger et al. 2004), but in agreement with results of Hartmann and Brown (1953) and Perica, Goreta, and Selak (2008) for his greenhouse study. The observed differences can be explained due to the age of the plants, cultivation methods, and soil and cultivar characteristics. ...
Article
The Leccino olive cultivar was grown in pots contained calcareous rendzina soil amended with NPK fertilizer (control treatment) or with further addition of Zeolite A (ZA) containing either zinc (Zn²⁺) or manganese (Mn²⁺) (Zn-ZA and Mn-ZA). After one year, vegetative growth and root morphological parameters were measured and elemental analysis was performed on the root, stem, and leaves. Compared to other treatments, the Zn-ZA fertilizer enhanced Zn concentration and total quantity in the root, stem, and leaves, as well as the root diameter. The root volume was greater using Zn-ZA treatment than control treatment. The total quantity of Mn in root and the root length were enhanced when using Mn-ZA compared to control or Zn-ZA treatment. According to the results of this study, it appears that zeolites containing Zn provide favorable conditions for Zn uptake in calcareous soils, while both Zn and Mn zeolites have a positive impact on olive root morphology.
... The 'Uzun' cultivar of pistachio (Pistacia vera L. 'Uzun') shows strong alternate bearing and this phenomenon may influence nutrient content and nutrient consumption in an alternating cycle, similar to that observed in other fruit tree species such as mandarin, (Mirsoleimani et al. 2014) and olive (Bustan et al. 2013;Fernandez-Escobar et al. 1999). To gain a more complete understanding of the physiological aspects of tree nutrition, we examined seasonal variations in the nutrient contents of the leaves and shoots of pistachio. ...
... As has previously been demonstrated in pistachio (Rosecrance et al. 1996;Picchioni et al. 1997;Rosecrance et al. 1998;Stevenson and Shackel 1998), olive (Erel et al. 2011;Bustan et al. 2013), pecan (Smith 2009), and apple (Cheng and Raba 2009). A decrease in the concentrations of P following an "On" year has previously been reported for pistachio (Picchioni et al. 1997;Rosecrance et al. 1998), olive trees (Fernandez-Escobar et al. 1999;Erel et al. 2008;Bustan et al. 2013), and 'Wilking' mandarin (Golomb and Goldschmidt 1987). Our results are consistent with previous findings in that we found that the rate of root growth is higher in "Off" trees than in "On" trees (Rosecrance et al. 1998). ...
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The relationships between alternate bearing and variations in mineral nutrient composition of the shoots and leaves of pistachio trees (Pistacia vera L. ‘Uzun’) and the effects of these relationships on flower abscission were investigated over 2 years (2015 and 2016). The mineral contents of leaves and shoots of “On” and “Off” year trees were measured at different periods of pistachio growth. Determination of total nitrogen (N) content was performed using a Kjeldahl instrument and other minerals were analyzed using the age-burning method via microwave digestion and by atomic absorption spectrometry. The concentrations of some minerals (P, K, Ca, Mg, Fe, Zn, Mn, and B) were higher in the leaves of “On” trees than in “Off” trees, while some others (N, K, Mg, Ca, Zn, and Cu) were higher in the shoots. The concentrations of N, P, K, Mg, Zn, and Mn in the leaves and shoots reached minimum levels during the flower abscission and nut kernel development period. Fruiting state had a significant effect on the contents of P, K, Zn, and Mg in both leaves and shoots, but did not affect the amount of N in these two organs. Levels of B, a sufficient supply of which is essential for successful flowering, in “On” trees decreased to deficient levels during flower blooming. Our results indicate that N, P, K, Ca, B, and Fe may play key roles in annual fruit production in pistachio and the changes in nutrient content during different development periods are associated with flower abscission.
... The leaf K, N and P concentrations decreased significantly from the first to the second sampling period. Our results are complemented by Fernandez-Escobar et al. [31], who stated that fluctuations in the nutrient content of the leaves during the plant growth cycle are attributed to the necessities of the crop depending on the developmental phase. Fernandez-Escobar et al. [31] reported that the nutrients which are the most important for the plant growth will be transferred faster to the roots than other nutrients, and they would be expected to increase in the second and the third sampling periods, when root development is at a vital point. ...
... Our results are complemented by Fernandez-Escobar et al. [31], who stated that fluctuations in the nutrient content of the leaves during the plant growth cycle are attributed to the necessities of the crop depending on the developmental phase. Fernandez-Escobar et al. [31] reported that the nutrients which are the most important for the plant growth will be transferred faster to the roots than other nutrients, and they would be expected to increase in the second and the third sampling periods, when root development is at a vital point. Our results indicated that K was the only macronutrient that presented a constantly increasing trait with time, as the highest K values were recorded in the third sampling. ...
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The present study examined the effects of different nitrogen (NH4NO3) and potassium (KNO3) fertilization levels in combination with a nitrogen-fixing, plant growth-promoting rhizobacteria (PGPR) inoculation on the carbohydrate (CHO), amino acid content, and nutrient concentrations (N, P, K) in the spears and the root system of asparagus plants. No significant differences were indicated between the different fertilization treatments regarding N, P, and K in the leaves and roots of asparagus. The inoculation of the asparagus fields with PGPR, no matter the type of the inorganic fertilizer, resulted in increased CHO and amino acid content of the foliage and roots of asparagus. The highest CHO content and amino acid content were recorded in the treatment that combined PGPR inoculation along with KNO3 fertilizer, indicating that higher K applications acted synergistically with the added PGPR.
... Impact of the plant mineral status on its phenolic profile is generally well known [9]. Olive cultivar as well as sampling/harvest time can both have a significant effect on OL phenolic compounds [3] and mineral content [10,11]. However, other studies show that while the content of oleuropein, as the main OL secoiridoid, can be markedly modified due to the genetic background, variations attributed to the collecting period can be insignificant [2]. ...
... Similar fluctuations in K concentration in leaves of cv. Picual during an "off" season have been reported by Fernandez-Escobar et al. [10]. ...
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In order to investigate the potential of various olive cultivars and leaf sampling times for phytochemical farming practice in Croatia, phenolic and mineral composition was determined in olive leaves of four Croatian cultivars and Italian cultivar Leccino collected at three occasions, in October 2017, January 2018, and March 2018. Istarska bjelica turned out to have the largest phytochemical potential among the investigated cultivars due to steady high oleuropein concentrations found in its leaves. The concentration of main phenolic components in Istarska bjelica leaves changed only slightly during the sampling period, suggesting the possibility of its higher capability for low air temperatures stress resistance and different metabolic response compared to the other studied cultivars. Low air temperatures increased the oleuropein level and antioxidant activity in leaves of Leccino, Oblica, Levantinka, and Drobnica cultivars, which may be of crucial phytochemical farming interest. Each of the investigated olive cultivars was characterized by a specific leaf mineral nutrient composition, which could have had a specific role in their interplay with phenols.
... Vegetation stress is a very complex physiological process which results in the decline in photosynthetic activity, less chlorophyll content, high dry matter content in foliage, increased none green pigments [9]. Stress in vegetation can also be triggered by fall in nutritional supply like N, P, K, Ca, Mg, Fe, Zn etc. [15][16][17][18][19][20]. Forest health can be estimated using remote sensing by means of chlorophyll content, foliar pigment and defoliation [21]. ...
Article
The present study deals with analyzing forest health, its parameters, and suitability of hyperspectral data for vegetation health-related studies. Sholayar reserve forest in Kerala has a huge reserve of equatorial moist evergreen forest and demands preservation in every respect. Due to increased human interferences coupled with possible climate change, its health is undergoing a stage of deterioration. Stress levels in the canopy were assessed using a number of stress-related pigments. Detailed study of vegetation response to canopy leaf pigments have been carried out in the study. Airborne Visible Infrared Imaging Spectrometer Next Generation (AVIRIS-NG) data provides immense possibilities to study a number of stress-related pigments like anthocyanin, carotenoid, lignin, chlorophyll-a, b etc. Dominant species in these forests are Holigarna arnottiana, Grevillea robusta, Grewia tiliifolia, Syzygium cumini, Alstonia Scholaris, Cinnamomum verum, Artocarpus heterophyllus, Bischofia javanica, Mangifera indica, Bombax ceiba, Anogeissus latifolia, Terminalia paniculata etc. Apart from luscious natural vegetation, plantation of teak (Tectona Grandis), rubber (Hevea brasiliensis), tea (Camellia sinensis), Coffee (Coffee Arabica), Palm-Oil tree (Elaeis guineensis) etc. also exists. Field data pertaining to one of the selected pigments was correlated with remotely sensed pigment estimates. Correlation of field measured chlorophyll concentration and EVI showed R2 = 0.421. Similarly, the anthocyanin index showed a correlation of R2 = 0.319. In the Sholayar Reserve Forest (493.0 km2) an area of 141.0 km2 was found to be in a healthy state. Whereas about 218.0 km2 of area exhibit moderately healthy condition and 77.0 km2 area was in the least healthy state.
... Magnesium did not appear to change in concentration over the 2-month sampling period in either year. While this appears to contradict Mg's phloem mobility, similar results have been observed in mineral resorption studies conducted with other plant species [26,42,43]. White [26] suggested that an ample supply of Mg in the soil solution precludes a pressure flow gradient in the phloem to spur resorption in response to sink demands. ...
... Olive fruit are a substantial sink for K, and therefore, after an 'On' year K reserves may be depleted [14,16]. More than any other nutrient, K concentrations in olive tree leaves, bark, and roots are influenced by the fruit load [16,46]. This effect of fruit load on the tree K levels may maintain and amplify the yield fluctuations of alternate bearing. ...
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The olive growing sector is transitioning from traditional to intensive irrigated cultivation, dictating a need to reconsider orchard management practices including fertilization. Potassium (K) is an essential nutrient, typically found in high concentrations in plants. Orchard K fertilization requirements are commonly derived from the disparity between assumed tree requirements and extractable soil K. The long-term impact of insufficient fertilization on K available in the soil, growth, and yield of irrigated field-grown olive trees was evaluated over six consecutive seasons. Withholding of K fertilization led to lower exchangeable and soluble K concentrations in the soil and significantly impaired yield. The reduction in yield was attributed to reduced flowering and fruit set, resulting in a lower fruit number. Tree vegetative growth and flowering quality traits were not affected. In addition, trees not receiving K appeared to be more susceptible to alternate bearing. Following two seasons of omitting K fertilization, leaf K concentration did not decrease below the conventionally accepted sufficiency threshold for olive (0.8%). In spite of this, the trees produced significantly lower yields. Our results suggest that long-term insufficient K fertilization results in reduced soil available K and consequently impairs tree productivity. The results imply that the sufficiency threshold for K in diagnostic leaves should be reconsidered for intensive orchards. Moreover, the current method for K deficiency detection using leaf K concentration may be inadequate for intensive orchards. Integration of other parameters, such as fruit K content, leaf Na, and changes in soil exchangeable K content or sorption energy, may promote a more reliable analysis of orchard K nutritional status.
... Especially for olive groves, this differentiation is probably due to the lower production in 2019 compared with 2018. Reduction in production for the following cultivation year is a result of alternate bearing, which is common in olive cultivation (Fernandez-Escobar et al. 1999). ...
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Energy flows in perennial agro and natural ecosystems are essential and could be related to greenhouse gas emissions and increasing water demands. Energy indices and carbon and water footprint are useful tools in assessing the interaction between production systems and environmental impact inside Natura 2000 sites and enhancing ecosystem services. The main aims of this study were to determine and compare energy indices, carbon and water footprint of olive groves, orange and kiwi orchards, and grasslands within and between 2 years, located in a Natura 2000 site, using an adjusted life cycle assessment (LCA) method; and to illustrate the importance of farming systems to ecosystem services. Proportional stratified sampling was used to select 36 farm types (12 olive groves, 12 oranges, and 12 kiwi orchards) and 12 grasslands from the municipality of Amfilochia, western Greece, during 2018 and 2019. Descriptive data analysis, correlational analysis, ANOVA, and hierarchical cluster analysis (HCA) were used to summarize and analyze the data. The main energy contributors for the three farm types were fertilizers and fuel consumption. The only input for the grasslands was animal manure. Energy efficiency showed the highest performance in olive groves followed in descending order by kiwi orchards, grasslands, and orange orchards. Concerning carbon-footprint, the values were the highest for orange orchards, followed in descending order by kiwi orchards, olive groves, and grasslands. Total water footprint values were the highest for grasslands and the lowest for olive groves. For both years, regarding HCA, each cluster consisted of the same ecosystems. According to the abovementioned indices, olive groves and grasslands are the most environmental friendly ecosystems. They could contribute in the environmental protection of the Amvrakikos Gulf, a Natura 2000 site. Kiwi orchards, although they are intensive along with the orange ones, seem to be more friendly to the environment than them and their cultivation in this Natura 2000 area is recommended. Energy indices and carbon and water footprint could be used, in order to highlight the related ecosystem (dis)services.
... In ExpF1, leaves taken by the standard procedure of the fertilizer recommendation programs, showed higher B concentrations in summer sampling in comparison to winter sampling. This finding had already been reported by other researchers (Fernández-Escobar et al., 1999;Chatzissavvidis et al., 2005;Arrobas et al., 2010;Rodrigues et al., 2012) and has led to the establishment of different sufficiency ranges for B, depending on whether sampling is done in summer, at endocarp hardening, or in winter, during the resting period of olive (LQARS, 2006;Therios, 2009). In any case, it seems that summer sampling better reveals situations of different availability of B in the soil than winter sampling, since the difference in leaf B concentrations from B treated and untreated plants was greater in summer sampling. ...
Article
Boron (B) has great importance in the fertilizer recommendation programs of olive, since B deficiency is a frequent nutritional disorder. This paper reports results of the olive response to applied B from two 3-year field trials (ExpF1, ExpF2) and two pot experiments (ExpP1, ExpP2). The ExpF1 was installed in a 3-year-old orchard and the ExpF2 consisted of planting young trees with the aboveground biomass yield being recorded. In ExpP1, B was applied to the soil or as a foliar spray to the whole of the canopy. The ExpP2 consisted of the application of B to selected parts of the canopy. The concentration of B in the existing tissues receiving the spray directly and in the new shoots developing after the B application was determined. The performance of the crop, including olive yield, did not increase in ExpF1 with soil-applied B. However, dry matter yield of young plants in ExpF2 significantly increased with B application. The application of B, both as a soil fertilizer and as a foliar spray, significantly increased the B concentration in all tissues and in all experiments. From ExpP1, soil applied B proved to be a more powerful tool of delivering high amounts of B to the plant than foliar spray. From ExpP2, B was shown to be mobile in the tree to some extent, although the mobility appears to be cultivar-dependent. In 'Arbequina' the older leaves that received the foliar spray showed higher B levels than the young leaves that developed thereafter, whereas in 'Cobrançosa' this difference was not observed.
... Trees take up calcium and magnesium from the soil at rates that vary with the temperature. However, Fernandez-Escobar et al.(30) reported that the amount of Mn and K in olive leaves increased steadily from the photosynthesis. Also, the amount of Mn increases during the growing season due to the increase in the soil temperature.Potassium is a highly mobile macronutrient which plays a vital role in protein synthesis, carbohydrate translocation, osmoregulation, enzyme activation, stomatal movement, and cell turgidity (33). ...
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Persimmon is a plant that is native to the Republic of Korea. It leaves are rich in antioxidants and minerals. This study set out to investigate the moisture, color, vitamin C, and mineral contents of five of the most common Korean persimmon leaves (‘Sangju-dungsi’, ‘Sangam-dungsi’, ‘Cheongdobansi’, ‘Gabjubaekmok,’ and ‘Suhong’), and how they varied with the applied drying technique (freeze-drying or hot-air drying at 100℃ for 30 min) and harvesting time (late May or late June). Persimmon leaves were first collected, and then blanched and dried. Our results revealed that freeze-drying was the most effective method in terms of the mineral content, while no significant difference in the vitamin C content was observed regardless of the drying method. The concentration of Mg, Ca, K, and Mn increased from May to June, while the opposite trend was observed for Na, Fe, Cu, and Zn. Persimmon leaves collected in late May had a higher vitamin C content than those harvested in late June. Ultimately, the ‘Sangam-dungsi’ persimmon leaf was found to have the highest mineral content, whereas ‘Gabjubaekmok’ leaves were richer in color (lightness, redness, and yellowness) and had the highest vitamin C content among the analyzed cultivars.
... The non-significant effects of application of micronutrient fertilizers might be due to low requirements of plants (Hassan et al., 2010). Fernandez-Escobar et al. (1999) concluded that olive trees have low requirement for micronutrients as they observed no effect of crop load on micronutrient accumulation in leaves during 'on' or 'off' years. However, application of fertilizers in this study had beneficial and elevating impacts on some other quality parameters of fruits, e.g. ...
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Present study was carried out to evaluate impact of micronutrients application (manganese, iron and zinc) with different methods (foliar or soil application) on quality parameters of 'Belidi' olive in Fars province. Chelated iron sequestrene 138, zinc and manganese sulfates were soil applied once a year and iron, zinc and manganese sulfate were foliar applied on plants, three times a year, alone or in combination. Results indicated that fertilizer application method did not have significant impact on tree productivity and fruit quality parameters in bearing or non-bearing years and alternate bearing in 'Belidi' olive trees was not correlated significantly with manganese, iron and zinc deficiency. It seems that foliar application of micronutrients fertilizers in regions with alkaline soils is a better strategy for improvement of olive production. © 2017 Society for Advancement of Horticulture. All rights reserved.
... Estos periodos de necesidades nutricionales se reflejan en los niveles de nutrientes en las hojas. Fernández-Escobar et al. (1999) mostraron que, en general, los niveles de N en hojas del olivo descendían ligeramente durante la primavera, cuando las hojas se están desarrollando en su plenitud, y subían en otoño, indicando cierta demanda de N durante primavera, aunque no se puede descartar movilización de nitrógeno desde otras partes del árbol hacia la hoja. Para el fósforo, el contenido foliar desciende más o menos abruptamente a partir de marzo, se alcanzan los mínimos valores durante agosto y septiembre y vuelven a subir durante los meses de noviembre, diciembre y enero. ...
... In the latter species, there is great variability in leaf K concentration between 'on' and 'off' years due to crop load. In this case, foliar application in the spring of the 'on' year is an effective way to apply K. Soon after the leaves have been sprayed with K, it is rapidly translocated to the reproductive structures of olive (Fernandez-Escobar et al., 1999), improving vegetative growth and fruit yield. Some studies, however, have reported irregular responses of fruit trees to foliar fertilizer applications (e.g. in apple, Khemira et al., 1999). ...
... The maximum value in Jun might have occurred because of the hot and dry weather of this period, which forces Ca ions to the leaves via transpiration stream. Fernandez-Escobar,Moreno and Garcra-Creus (1999) reported results similar to the previously mentioned ones.MagnesiumLeaf Mg concentration was at high levels (0.18% DM) during the period of endocarp hardening and fruit maturation (Jul -Nov) (Figure 5). The maximum values occurred in Nov (0.2% DM). ...
Article
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Leaves of olive (Olea europaea var. minor rotunda) were collected from mature non–irrigated trees in an “off” year, at monthly intervals, from May 2015 to April 2016. Leaf concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn) and boron (B) were determined. Seasonal fluctuation curves were developed for each nutrient, in order to use them for interpretation of leaf analysis. Concentrations of N, P, K, Ca and Mg showed significant fluctuation throughout the year, while B, Fe, Mn and Zn showed less intense changes. Nutrient accumulation varied according to tree vegetative growth and weather conditions.
... Low calcium levels may be linked to cal- cium seasonal leaf fluctuation. 60 ...
Article
BACKGROUND The aim of this study was to examine the effect of foliar (Mn_fol) and soil Zeolite‐Mn (Mn_ZA) application on leaf mineral, total phenolic and oleuropein content, and mycorrhizae colonization of self‐rooted cv. Leccino plantlets grown on calcareous soil. RESULTS The dissolution of zeolite was 97% when citric acid was applied at 0.05 mM dm‐3, suggesting that organic acids excreted by roots can dissolve modified zeolite (Mn_ZA) making Mn available for plant uptake. The leaf Mn concentration was the highest for Mn_fol treatment at 90 DAT (172 mg kg‐1) and 150 DAT (70 mg kg‐1) compared to other treatments. Mn_ZA soil application increased leaf Mn concentration at 150 DAT compared to control and NPK treatment. The oleuropein leaf content was highest for Mn_fol compared to other treatments at 90 DAT and lowest at 150 DAT. Arbuscular mycorrhizal colonization was higher for Mn_fol treatment at 150 DAT compared to all other treatments. CONCLUSION Changes in the arbuscular colonization percentage and oleuropein content may be connected to stress conditions provoked by high leaf Mn concentration in Mn_fol treatment at 90 DAT. Mn_ZA application increased leaf Mn concentration at 150 DAT compared to control and NPK treatments. It can be assumed that the dominant mechanism in Mn uptake from modified zeolite is Mn_ZA dissolution through root exudates. This article is protected by copyright. All rights reserved.
... Fernandez-Escobar et al., 1999 . ( ...
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Rhizosphere soil samples were collected from olive orchards of Golestan, Guilan, Zanjan and Qom provinces. Fluorescent pseudomonad strains were isolated from the collected samples on King’s B medium and their phenotypic features characterized as based on the standard bacteriological methods. For all the tested strains oxidase reaction, fluorescent pigment, growth at 4˚C and arginine dihydrolase were positive while tobacco hypersensitivity reaction, levan production on 5% sucrose and pectolytic activity on potato slices were proved negative. Most of the tested strains reduced nitrate while liquidizing gelatin. Based upon the phenotypic features of the tested strains most were identified as P. fluorescns while a few identified as P. Putida. Nematicidal activity of the cultural filtrate of the Psudomonas strains was tested on fresh hatched juvenile of Meloidogyne javanica under laboratory conditions. They caused nematode mortality ranging from 13.33 to 100% while showing significant differences. Efficacy of the representative strains along with fenamiphos on nematode egg productions, juvenile and mature nematode activity on olive root were studied under green-house conditions. Significant differences were observed among the applied treatments. The highest and lowest nematode juvenile and mature formation on olive seedling roots were observed for control plants and plants treated with fenamiphos respectively. The most effective strains on the different nematode life stages were P. fluorescens strains CHAO as well as strain 208. The highest and lowest nematode egg production on olive seedling roots were observed for control plants and plants treated with strains CHAO vs. strain 99 respectively. Some strains proved to be more effective than fenamiphos in nematode egg production on olive seedlings roots. This is the first report of the biocontrol of olive root knot nematode using flourescent pseudomonads.
... Unlike animal food, the number and diversity of nutritional compounds of leaves and fruit varies with plant species, location, position on the tree, stage of development, and even time of day [27,[81][82][83][84]. Therefore, it is reasonable to assume that catarrhine primates require more sensitive and specific sweet and umami tastes when compared to carnivorous animals. ...
... Our findings suggest that either plant growth at medium and high intensity developments is higher than in open areas leading to diluted BAF values in the plants or plants in open areas have leaves that live longer than in more developed areas leading to higher TMM accumulation. For example, shrubs in drier, nutrient poor soils in the open areas outside of the city can have older leaves which can bioaccumulate TMMs over several seasons (e.g., Fernandez-Escobar et al. 1999). Further, the wetter areas near Los Angeles can have greater photosynthesis and growth rates, causing a carbon dilution effect (Jarrell and Beverly 1981;Miller 1982;Anderson and Goulden 2011). ...
Article
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Purpose Southern California is a mega-metropolitan area with abundant air pollution, complex geology, and diverse Mediterranean ecosystems. The objective of this study was to evaluate trace metal and metalloids (TMMs) (As, Cd, Co, Cr Cu, Ni, Pb, U, V, Zn) in soils and foliage of peri-urban areas and explore potential effects from human-development, ecosystems, and geologic material. Materials and methods Foliage of dominant native vegetation, soil samples (0–20 cm), saprolite, and unweathered rock samples were collected across fifty-four sampling sites in foothills spanning coastal Los Angeles and Orange counties to inland San Bernardino and Riverside counties. Results and discussion Soil As, Cd, Cu, and Pb concentrations were regionally elevated, but not as elevated as point-source polluted sites elsewhere. Soil Cd, Cr, Cu, Pb, and Zn concentrations were above EPA Ecological Soil Screening Levels. Further, enrichment factors (EF) normalized to Ti concentrations in bedrock suggest minor to moderate As, Cd, Cr, Cu, Pb, and V accumulation in soils. Our foliar TMM concentrations and bioaccumulation factors (BAF) (foliar and soil ratio) indicate no bioaccumulation and limited effects across geologic, development intensity, and ecosystems groups. Conclusions Sedimentary-derived soils affected soil TMMs, but likely not through inheritance of TMMs but by promoting clay and organic matter availability. Proximity to higher development intensity resulted in As, Cd, Cr, Cu, and Pb accumulation in peri-urban soils. Foliar TMM concentrations and BAFs suggest geologic materials, human development, and ecosystem properties were not important factors and TMMs were likely controlled by plant uptake or ecophysiology.
... Previous research indicates that N contents have minimal value in the fruiting stage [52]. After spray application of 3% sugar, the N content showed a significant increase when compared with that in the control, which indicates that exogenous sucrose can solve the problem of a low N content in the fruit abscission stage. ...
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Background: Nutrient deficiency leads to a high fruit abscission rate in Sapindus mukorossi Gaertn. (Soapberry), which is one of the most widely cultivated biodiesel feedstock forests in China. Exogenous sucrose can provide a solution to nutrient deficiency and fruit abscission, which was applied to whole trees at two stages, 20 days before blooming (DBB stage) and fruit abscission (DBFA stage). Six sucrose concentrations, 0%, 1%, 1.5%, 3%, 5% and 7%, were sprayed three times at a completely randomized block design with 5 replications and 6 treatments. 13CO2 labelling experiments were carried out after the 3 sprayings. Results: (1) In the DBB stage, the 3% treatment significantly increased the inflorescence fructose and glucose contents 1-1.2 times, also resulted in the highest fruit GA3, leaf IAA, fruit IAA and fruit ZT contents, while it decreased the inflorescence ABA from 16 μg/g to 4 μg/g. (2) The 1.5% and 3% treatments significantly increased the carbohydrate content and decreased fruit ABA content to 30%-50% of the control level in the DBFA stage. (3) High-concentration sugar treatment (over 3%) increased the nitrogen, phosphorus, and potassium contents, which decreased the calcium and magnesium contents. (4) The ¹³C-dispatching ability of the inflorescence was 3 times greater than leaves under high-concentration sugar treatment in the DBB stage. Supplying 1.5% sucrose nearly doubled the allocation capacity in the DBFA stage. (5) The source-sink nutrient migration pathway showed that leaf and fruit sugars were directly correlated via phosphorus. Fruit fructose and glucose contents affected the leaf mineral element contents. Conclusions: It can conclude that exogenous application of 3% sucrose in the DBB stage and 1.5% sucrose in the DBFA stage can increase the sink nutrition allocation capacity, and phosphorus is the main mineral element correlated with leaf and fruit sugars.
... To the best of our knowledge, no previous studies evaluating the effects of combined S and N nutrition on the olive oil nutritional quality and olive fruit morphological parameters have been reported to date. Determination of leaf nutrient status is the best method for predicting the tree nutritional requirements and, consequently, for planning future fertilization [29]. Carciochi et al. [30] published that N fertilization increased S concentration and uptake, similar to other authors who observed the synergistic effect of these two nutrients [7]. ...
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This study investigates the effect of combined sulfur (S) and nitrogen (N) foliar fertilization on leaf S and N concentration, as well as on the growth of olive fruit and on the quantity and quality of olive oil, obtained from two olive cultivars ‘Istarska bjelica’ and ‘Leccino’ in two consecutive years. S and N are some of the most important nutrients, and both play a crucial role in plant oil production. The here-reported fertilization program significantly increased S concentration in leaves without affecting N concentration, which led to an increase in fruit yield and improvement of all fruit morphological parameters. The best oil yield per tree was obtained under the treatment with the highest S/N dose. Oil quality was not affected by S and N supply, and this allowed us to classify all our oil samples as extra virgin (EVOO). Regarding the content of total phenols (TPC) and composition of fatty acid methyl esters (FAME), they remained unaltered under the applied treatments. All investigated fruit morphological parameters, as well as fruit and oil yield, were highly cultivar-dependent. ‘Istarska bjelica’ was characterized as a cultivar with higher fruit mass and pulp percentage, while its stone parameters were lower than those of ‘Leccino’. Consequently, the extraction oil yield obtained from ‘Istarska bjelica’ fruits was much higher. Moreover, environmental conditions had a great impact on fruit and oil quantity. The here-obtained results led us to the conclusion that supply of S and N can enhance oil production without affecting its nutritional quality, a finding that could generate large long-term effects on economic growth in the olive oil sector.
... Our study showed up-regulation of potassium ion channel, magnesium dechelatase (SGR), magnesium-chelatase subunit (ChlH), CSC1-like protein (Calcium-dependent channel) and calcium permeable stress-gated cation channel (TMEM63) during in "OFF" inflorescence buds. Some studies found that N, K, Ca and Mg content were affected by crop load in olive leaves, showing lower values following the "ON" year [45]. However, the information on the effects of fruiting on nutrient concentrations of different organs of pistachio trees relative to bud abscission is limited. ...
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The alteration of heavy (“ON/bearing”) and light (“OFF/non-bearing”) yield in pistachio (Pistacia vera L.) has been reported to result from the abscission of inflorescence buds on high yielding trees during the summer, but the regulatory mechanisms involved in this bud abscission remain unclear. The analysis provides insights into the transcript changes between inflorescence buds on bearing and non-bearing shoots, that we indicated as “ON” and “OFF”, and shed light on the molecular mechanisms causing premature inflorescence bud abscission in the pistachio cultivar “Bianca” which can be related to the alternate bearing behavior. In this study, a transcriptome analysis was performed in inflorescence buds of “ON” and “OFF” shoots. A total of 14,330 differentially expressed genes (DEGs), most of which are involved in sugar metabolism, plant hormone pathways, secondary metabolism and oxidative stress pathway, were identified. Our results shed light on the molecular mechanisms underlying inflorescence bud abscission in pistachio and we proposed a hypothetical model behind the molecular mechanism causing this abscission in “ON” shoots. Results highlighted how changes in genes expressed in nutrient pathways (carbohydrates and mineral elements) in pistachio “ON” vs. “OFF” inflorescence buds triggers a cascade of events involving trehalose-6-phosphate and target of rapamycin (TOR) signaling, SnRK1 complex, hormones, polyamines and ROS which end, through programmed cell death and autophagy phenomena, with the abscission of inflorescence buds. This is the first study reporting gene expression profiling of the fate of “ON” and “OFF” inflorescence buds associated with the alternate bearing in the pistachio.
... Therefore, there is a possibility that the addition of leaf during oil extraction could increase the concentration of hemicellulose and consequently reduced the concentration of phenols in oils. Olive leaves contain significant amounts of minerals: potassium, manganese, magnesium, copper, and iron being the most common ones [50,51]. Several metals, as iron and copper, could have an important role in degradation of phenolic compounds [52]. ...
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The effect of the addition of different amounts of olive leaf (1, 2.5, and 5%, m/m) during Buža olive cv. oil production on the quantitative production parameters, composition, and sensory characteristics of the obtained oils were investigated in this study. The addition of leaf during oil extraction increased oil yield and extractability index by 97% compared to the control oil. The addition of leaf during extraction increased the concentration of pigments in oils, and the oil positive sensory attributes intensities, such as fruitiness and green grass/leaf notes. The influence on oil phenolic composition was dependent on the amount of leaf added. When 1% leaf was added, most of the phenolic compounds were preserved, while the addition of leaf at 5% decreased the concentration of the majority of phenols, especially secoiridoids by 45% compared to the control oil. The addition of leaf slightly increased the concentration of fatty acid ethyl esters and waxes in the oils. The obtained results indicate that particular importance should be given to the amount of olive leaf present in olive paste during oil extraction, since it apparently can increase the extractability of oil, but can also have negative effects on phenolic composition when added in excess.
... In fact, leaf K concentrations were greater in Off-than On-trees. According to Fernandez-Escober, Moreno, and Garcia-Creus (1999) we conclude that the high leaf K accumulation following the Off-year and the rapid decline after March of the Onyear suggest a large K demand by the reproductive structures of pistachio. In addition, based on the norm of leaf K critical value of 1% proposed by Beede et al. (2005), the Off-year trees were approaching the normal range. ...
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... Olive leaves and twigs treated with 4% urea were introduced to growing sheep ration at a level of 30% in replacement to berseem hay without adverse effects on growth performance (Aziz et al., 2009). Copper content of olive leaves was reported to be high ranging from 10 to 80 mg/kg DM due to the fungicide application (Fernández-Escobar et al., 1999). A short term trial of 27 days on sheep and goat showed that high level of cupper might restrict use of olive leaves in practical ruminant nutrition (Yáñez-Ruiz et al., 2008). ...
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... Effect of RAPA on IL-6 and TNF-α production in LPS-treated RAW 264.7 cells. The role of cytokines in inflammation is very important, and TNF-α and IL-6 are considered representative pro-inflammatory cytokines, as they both regulate the inflammatory response (29). Herbs such as Rehmannia glutinosa and Suaeda japonica are known to inhibit inflammation by regulating IL-6 and TNF-α expression (30,31). ...
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The major bioactive compounds present in different extracts of olive leaves (olive leaf) are apigenin, luteolin, oleuropein, verbascoside, and the triterpenoids (oleanolic and maslinic acids). Aspects of sampling, postharvest treatment, and extraction of the compounds from the leaves are discussed. Regarding bioactivities, effects related to the four most important noncommunicable diseases, namely, cardiovascular, cancers, respiratory diseases, and diabetes are presented in more detail.
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Leaf analysis is a tool for effective fertilizer recommendations in fruit trees. To achieve this goal, a suitable leaf sampling method is a very important step. This study aimed to investigate suitable leaf position and leaf age to establish standardized leaf sampling method, which can collect representative leaf sample for leaf nutrient analysis in rose apple cultivar Tubtimjan. The experiment consisted of 3 leaf positions (1st, 2nd, and 3rd leaf position) from the growing tip and 1-8 months leaf age. The results indicated that the suitable leaf position to be the index leaves were 2nd and 3rd leaf position with 6–7 months old leaf age due to minimum variation of the leaf nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) concentrations. Moreover, the concentrations of N, P, and K tended to decrease, whereas, Ca, Mg, Fe, Cu, Mn, and Zn concentrations tended to increase as leaf age increased.
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In this study, we investigated seasonal variations in the mineral nutrients in Fremont cultivar budded on different citrus rootstocks in Dörtyol-Hatay (Turkey). Nitrogen (N), phosphorus (P) and K (potassium) contents in the leaves showed slightly similar trend with one another, in general these nutrients reduced from January to March-April, and the increases continued during the growing season until mid– and late summer, then decreased until December. Similar trends were found in calcium (Ca) and magnesium (Mg) contents. In the leaves, Ca and Mg concentrations decreased from January to March, then increased during fruit development until July-August and then reduced during autumn and winter. Also, micro elements such as iron (Fe), zinc (Zn), manganese (Mn) and copper (Cu) increased from January to May-June, then decreases began during the growing season until December. In the entire growing season, mean macro nutrients such as N, K and Ca contents changed from 2.15% (sour orange) to 2.29% (Carrizo citrange), from 1.09% (Carrizo citrange) to 1.19% (sour orange) and from 2.67% (sour orange) ile 3.15% (Carrizo citrange), respectively, P and Mg contents showed slightly similar trend with %0.13-0.15 and %0.32-0.34, respectively. Mean micro nutrients such as Fe, Zn, Mn and Cu contents ranged between 69.50 and 74.41 ppm, between 32.76 and 37.76 ppm, between 61.82 and 72.26 ppm, and between 10.5 and 10.8 ppm, respectively. It can be concluded that there are considerable differences in nutrient uptake ability of rootstocks.
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Background Olive-trees (Olea europaea L.) are the dominant rustic trees cultivated in the Mediterranean agricultural zones. Major and micronutrients play an indispensable role in their plant physiological functions although; the effect of trace elements on metabolic processes has not been sufficiently investigated, especially in olive-trees. Methods In the current study, we have used X-ray fluorescence (XRF) spectrometry to determine selected major and trace elements (Br, Cu, Fe, K, Mn, P, Rb and Zn) in the main olive cultivar cultivated in Algeria, cv.‘Sigoise’. Certified reference materials viz. IAEA-336 (Lichen) and NIST-1646a (Estuarine sediment) were evaluated simultaneously with the soil and plant samples for quality control of the analytical method. Results The results show that Fe and Mn concentrations were superior in leaves than fruits. However large amounts of K, Cu and Rb were accumulated in the olive-fruits. The contents of all chemical elements were above the threshold limits for possible plant nutrient deficiencies, except for P whose concentration was in borderline requirement of olive trees. High values of a translocation factor index were found for K, Cu and Rb (TFs > 4). Principal component analysis (PCA) indicated that K was highly related with olives-fruits, suggesting that the fruit was the principal organ of K storage. Furthermore, dietary element intake through consuming olives was also estimated and compared to recommended daily intakes (RDIs) and daily permissible limits (DPLs). The estimations of chemical element intakes were below the DPLs set by WHO/FAO guidelines for human nutrition. Conclusion The present work indicates that the concentrations of macro- and microelements (Cu, Fe, K, Mn and Zn) were above the threshold limits for possible plant deficiencies except for P, and this cultivar can easily accumulate high amount of K in their organs (predominance in olives). These findings will be used to achieve efficient fertilization for O. europaea orchards.
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The relative water content (RWC) provides a measurement of the water deficit of the leaf and may indicate a degree of stress, endured under conditions of drought and high temperatures. Its measurement is therefore essential for the appropriate management of irrigation. This study sought to ascertain the viability of near infrared spectroscopy (NIRS), using a handheld portable NIR instrument, for the non-destructive and in situ determination of RWC in olive tree leaves cultivated under higher temperatures than ambient. Different combinations of pre-treatments and first and second derivative were assayed to obtain information of spectral data and to develop calibration models. A calibration equation with enough prediction performance to support irrigation decision-making (standard error of cross-validation, SECV = 1.52%; r²cv = 0.61; residual predictive deviation for cross-validation, RPDcv = 2.01) was obtained. The findings obtained from the external validation of the model (standard error of prediction, SEP = 1.63%; r²p = 0.64; residual predictive deviation for prediction, RPDp = 2.17) suggest the viability of the on-tree use of NIRS technology for the instant measurement of RWC in olive groves, ensuring a major saving in time and avoiding the disadvantage of transporting samples to the lab, thereby favouring real-time decision-making in the field regarding the optimal amounts of irrigation to be applied; this is of enormous significance for the future, given that the availability of irrigation water for such vital crops to the Mediterranean region as the olive could be limited in years to come by a gradual increase in global temperature.
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Background and purpose: Essential oils are volatile components of plants. Some essential oils with phenolic compounds have a strong antimicrobial properties. Probiotics are live microbial food supplements which beneficially affect host by improving its intestinal microbial balance, and they are well recognized as antimicrobial agents that compete with pathogenic bacteria and inhibit their growth. Various types of probiotic bacteria have different sensitivities to essential oils. Some essential oils increase the growth of probiotics and some others decrease the growth or inhibit that. Simultaneous use of herbal essential oils and probiotics is a new approach in preventing growth of pathogenic bacteria in food, therefore, this study aimed at evaluating researches conducted in Iran about the effect of medicinal plant essential oils on the performance of probiotic microorganisms. Materials and methods: A literature search was conducted in electronic databases including Pubmed, Science Direct, Elsevier, SID, Magiran, and Google Scholar and articles published from 2006 until 2016 (the last decade) were selected. The search keywords included medicinal plants, probiotics, and growth inhibition. Results: The studies showed that compounds found in essential oils have different functions on probiotic bacteria. In other words, in some cases they acted as amplifiers and in some they showed inhibitory effects. Conclusion: Essential oils of oregano, olive leaf, malt, cinnamon, garlic, dill, cumin, soy, and peppermint have positive effects on the growth of probiotic bacteria, while Kelussia, thyme, Teucrium polium and simultaneous use of oregano and Ziziphora have negative effect on probiotic growth. © 2016, Mazandaran University of Medical Sciences. All rights reserved.
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All leaves from 10 replicate Cocos nucifera L. 'Malayan Dwarf' (COC) and Phoenix canariensis Chabaud (CID) trees were sampled for leaf nutrient analysis. In addition, the leaflets of the youngest fully expanded leaves and the third oldest leaves were divided into five groups along the primary leaf axis and these leaflets were then cut into thirds to determine nutrient distribution patterns within leaves and leaflets. Nutrient remobilization rates were calculated for N, P, K, Mg, and Mn. Results showed that N, P, and K were highly mobile within and between leaves of both species of palms. Up to 31% of the N, 66% of the K, and 37% of the total P in the oldest leaves were ultimately remobilized to newer leaves within the palm. Magnesium remobilization rates averaged ≃71% for CID but only ≃10% for COC. The middle-aged leaves appeared to be the primary sink for Mg in COC, rather than the youngest leaves as in CID. Manganese was also quite mobile in both species, with up to 44% of the total Mn remobilized in CID. Samples consisting of recently matured leaves were determined to be the most appropriate for Ca, Fe, Mg (COC only), and Zn, but oldest leaves are more suitable for N, P, K, and Mn analysis.
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GA 3 scaffold injections applied between May and November to nonbearing olive (Olea europea L.) trees inhibited flowering the following year, increased shoot width when applied in May, June, and July, and increased inflorescence length when applied in November and February. Fruit removal and seed destruction were effective in improving the return bloom in `Manzanillo' olives when done before endocarp sclerification. Depending on-the year, endocarp sclerification takes place 7 to 8 weeks after full bloom (AFB), usually about 1 July. Fruit removal had no effect on flowering when done after this time. Scaffold injection of paclobutrazol applied to bearing trees between May and September did not affect flowering the following year. The results of our research supports the hypothesis that olive flower induction occurs around the time of endocarp sclerification. Chemical names used: gibberellic acid (GA 3 ), (2RS,3RS)-1-(4-chlorophenyl)-4-dimethyl-2-1,2-4-triazol-1-yl) pentan-3-ol(paclobutrazol).
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Chlorotic 'Manzanillo' olive (Olea europaea L.) trees and 'Maycrest' peach [Prunus persica (L.) Batsch] trees were injected with Fe solutions using an apparatus that consisted of a plastic injector and a pressurized latex tube containing the solution to be injected. Injections were made on various dates from Sept. 1987 to July 1988. All treatments increased chlorophyll content compared to that of the control. Ferrous sulfate was the most effective Fe compound in alleviating chlorosis; its effect lasted for two seasons in peach and for at least three seasons in olive. Also, ferrous sulfate increased vegetative growth and affected cropping the year following injections. Ferrous sulfate at 0.5% to 1% is recommended to reduce the risk of foliar burning. The injection method effectively introduced Fe compounds into olive and peach trees.
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Additional index words. Prunus domestica, fruit crops, nonstructural carbohydrate, 15 N, potassium, source–sink relationships Abstract. Four adjacent heavily cropping 12-year-old 'Petite d'Agen' prune (Prunus domestica L.) trees were selected, and two of the trees were defruited in late spring (28 May) after the spring growth flush and full leaf expansion. Trees received K daily through the drip-irrigation system, and 15 N-depleted (NH 4) 2 SO 4 was applied twice between the dates of defruiting and fruit maturation. Trees were excavated at the time of fruit maturity (28 July) and fractionated into their component parts. The following determinations were made after tree excavation and sample processing: tree dry weight, dry weight distribution among the various tree fractions (fruit, leaves, roots, trunk, and branches), tree nutrient contents, within-tree nutrient distribution, total nonstructural carbohydrates (TNCs), and recovery of labeled N. Trees only recovered ≈3% of the isotopically labeled fertilizer N over the 6-week experimental period. Heavily cropping trees absorbed ≈9 g more K per tree (17% of total tree K content) during the 2-month period of stage III fruit growth than defruited trees. The enhanced K uptake in heavily cropping trees was apparently conditioned by the large fruit K demand and occurred despite greatly reduced levels of starch and TNCs relative to defruited trees. Fruit K accumulation in heavily cropping trees was accompanied by K depletion from leaves and perennial tree parts. Except for K, fruited and defruited trees did not differ in nutrient content.
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Estimates of leaflet and fruit macronutrient (N, P, K, Ca, and Mg) accumulation and resorption were developed in six (three heavily cropping, on-year and three noncropping, off-year) mature pistachio (Pistacia vera L. 'Kerman') trees over three growing seasons during three stages of phenology [the spring growth flush (April to June); seed fill Gate June to September); and leaf senescence (September to November)]. Crop load influenced total nutrient content per tree in annual organs (leaves and fruit), the relative allocation of nutrients between leaves and fruit, temporal patterns of nutrient accumulation in annual organs, and the magnitude of net leaf nutrient resorption per tree prior to leaf fall, In off-year trees, macronutrient accumulation in annual organs (leaves) was concentrated during the spring flush of growth. In contrast, significant macronutrient accumulation in annual organs of on-year trees (leaves plus fruit) occurred not only during the spring flush of growth but also during seed fill, Duration and magnitude of macronutrient accumulation were greater in on-year vs, off-year trees, Fruit N and P demand during seed fill was partially met by a net decrease in the N and P contents of the pericarp, These decreases in pericarp nutrient content during seed fill were equivalent to 32% and 26% of embryo accumulation of N and P, respectively, Fruit demand for N, P, and K during the spring flush of ''on'' years was accompanied by reduced leaf N, P, and K contents per tree, Net leaf N, Ca, and Mg resorption per tree during leaf senescence differed with crop load, Net leaf N resorption was significantly greater in off-year trees than on-year trees, Leaf N resorption presumably represents an important component of the N pool stored in perennial tree parts during dormancy, The greater leaf N resorption following ''off' years was a function of greater leaf N concentration and greater leaf biomass per tree, In contrast, net leaf resorption of Ca and Mg was greater in on-year vs, off-year trees, Experimental validation of the magnitude and periodicity of nutrient uptake by mature pistachio trees is needed during the alternate-bearing cycle, especially in light of the potential contribution of current fertilization practices to groundwater contamination.
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Concentrations of N, P, K, Ca, Mg, B, Fe, Cu, Zn, and Mn in mature commercial fig ('Calimyrna'; 'Sari Lop') leaves are presented throughout the growing season. These data can be used as preliminary norms for the interpretation of tree nutrient status for high-yielding commercial fig orchards. In comparison with other deciduous tree crops growing in the same regions {almond [Prunus amygdalus Batsch syn. P. dulcis (Mill) D.A. Webb], walnut (Juglans regia L.), peach [Prunus persica (L.) Batsch]}, productive fig trees have relatively low leaf N, P, and K concentrations (2.1 %, 0.1 %, and 1.0% dry weight, respectively) in July, although tissue Mn and Ca concentrations often exceed those typically found in other deciduous species growing in the same soils. Seasonal variations in fig leaf nutrient concentrations are similar to those of other tree crops. Marked declines in tissue K and N concentrations toward the end of the season may indicate a need for supplemental N and K fertilization in highly productive orchards. The potential for K deficiency in fig also is indicated by the generally lower leaf K concentrations in the low-vigor orchards examined.
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Change in B content of olive (Olea europaea L.) leaves during anthesis reveals the appearance of a potent B sink. This phenomenon was more marked in young leaves of bearing trees with a high degree of flowering than in nonbearing trees with a low degree of flowering. Applying B to the leaves at the time of anthesis increased the B concentrations in leaf blades, petioles, bark of the bearing shoot, and flowers and fruit 3 days after treatment. The results suggest that B is mobilized from young leaves during anthesis to supply the requirements of flowers and young fruit.
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Experiments with heavily-flowering olive trees showed only one period of abscission of flowers and fruit in the 5-6 weeks following full bloom. This abscission of flowers and fruit is responsible for the small percentage of fruit retained to maturity. Most of the fruit drop was concomitant with initial fruit growth for all cultivars. There were no differences in the number of fruit per inflorescence among cultivars, but the percentage of inflorescences with fruit at harvest was related negatively to final fruit size for each cultivar. Thinning of perfect flowers within the inflorescence did not affect fruit set at the inflorescence level; thus, the inflorescence behaved as a unit of fruitfulness. Competition among fruits played a significant role in fruit set. Initial setting induced by pollination and fertilization is counteracted early by fruit abscission originated by competition among fruit. In light of this early abscission, the use of fruit set to indicate response to pollination in previous experiments is questioned.
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A single solution reagent is described for the determination of phosphorus in sea water. It consists of an acidified solution of ammonium molybdate containing ascorbic acid and a small amount of antimony. This reagent reacts rapidly with phosphate ion yielding a blue-purple compound which contains antimony and phosphorus in a 1:1 atomic ratio. The complex is very stable and obeys Beer's law up to a phosphate concentration of at least 2 μg/ml.The sensitivity of the procedure is comparable with that of the stannous chloride method. The salt error is less than 1 %.
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The date of full bloom for olive (Olea europaea L.) tree varieties planted in the World Collection in Córdoba, Spain, has been determined from 10 years of data. The full bloom dates were analyzed using three methods to develop a model predicting flowering time. The method of heat units accumulated before flowering was the most accurate. The heat accumulation periods were determined from phenological and temperature data. Prediction methods were evaluated for the earliest-flowering variety, a model variety representing the mean values for the collection, and the latest-flowering variety. The most appropriate threshold temperature for heat accumulation has been confirmed to be 12.5C; it can be used to predict the flowering time in olive.
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The influence of alternate bearing on nutrient utilization and total tree nutrient content was investigated in mature pistachio (Pistacia vera L. cv Kerman trees). Removal of N, P and Zn in fruit and abscised leaves of cropping (‘on’) trees averaged 5, 6, and 2 times, respectively, the removal in abscised leaflets of the non-fruiting, ‘off’ year trees. One hundred and thirty-five kg N, 131 kg K, 86 kg Ca, 39 kg Mg and 18 kg P per hectare were removed in fruits and abscised leaves in ‘on’ year trees. Tree nutrient contents and, presumably, the size of nutrient storage pools in dormant trees varied between ‘on’ and ‘off’ years. There was 22% and 14% more N and P, respectively, in dormant trees following ‘off’ than ‘on’ years. The greater N and P accumulation in ‘off’ year trees is depleted in support of the large fruit demand for N and P during ‘on’ years. In contrast to N and P, there was greater K and Ca accumulation in perennial tree parts during ‘on’ years than during ‘off’ years. The greater K accumulation in perennial tree parts and approximately 30% greater removal of K in annual organs during ‘on’ than ‘off’ years suggests that K uptake could be 4 times higher in ‘on’ year trees than in (non-cropping), ‘off’ year trees.
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The concentrations of macro- and micro-nutrients within leaves and fruit of Japanese pear (Pyrus serotina Rehder var. culta Rehder) trees were recorded over one growing season. Separate determinations were made for leaves on spurs and leaves on extension shoots. Numbers and dry weights of leaves and fruit on these trees were also measured to allow estimation of the quantities of nutrients accumulated within the deciduous organs of the tree. The cumulative canopy leaf dry weight increased until just prior to fruit harvest when leaf growth slowed considerably. There was relatively little increase in the leaf biomass after fruit harvest. Vegetative pruning, carried out on two occasions during the summer, appeared to have no significant effect on the subsequent rate of leaf growth. The dry weight of individual fruit increased exponentially until harvest. The rate of water accumulation within the fruit was more rapid than that for dry weight, with the ratio of dry weight:fresh weight declining during fruit development.
The time of floral induction in the olive Overcoming iron chlorosis in olive and peach trees using a low-pressure trunk-injection method Estado nutritivo de las plantaciones de olivar en la provincia de Granada Chemical analysis of plant tissue
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Changes in carbohydrate and nitrogen content of Souri olive leaves in relation to alternate bearing
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Leaf analysis for California deciduous fruits
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