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The aim of the study was to evaluate the effect of type of irrigation and of amount of water supplied on vine growth, yield and fruit quality at harvest and after 2 and 4 months of cold storage. The study was carried out in 2019, in northern Italy, on kiwifruit Gold 3®(A. chinensis var. chinensis) grafted onto micro-propagated 'Hayward' (A. chinensis var. deliciosa) rootstocks in 2012, planted at a distance of 4.5×2 m apart. The investigated irrigation systems included: 1) control (T0); 2) drip irrigation with a single line (T1); 3) drip irrigation with double lines (T2); 4) sprinkler (T3); 5) drip irrigation with double lines + sprinkler (T2+T3). Water management in the control treatment was carried out with drip irrigation with a single pipeline according to the advisory service, based on daily evapotranspiration only. In T1, T2, T3, and T2+T3 water was applied according to the soil water content measured by potentiometric probes, located at two depths: 0.20 and 0.60 m, and two distances from the line of the trees: 0.20 and 1 m. Irrigation started when soil water content got down below the field capacity (-0.03 MPa) and returned the same amount of water lost the day before and measured by a PAN evaporimeter. Compared to the control, T1 reduced the volume of water applied by 34%, T2 by 3%, while T3 increased the irrigation volume by 14% and T2+T3 by 17%. Sprinkler application induced an excess of water in the inter row, where soil structure was impaired by the frequent passes of machines, reducing soil permeability. No effect of treatments on vine yield was observed, however, fruit soluble solid concentration and fruit dry matter at harvest was increased by T2 compared to the other treatments. A similar response was also found after 2 months of cold storage, but disappeared after 4 months. The incidence of storage break down (SBD) was higher in fruits of the control and T3 (22 and 40% of the fruits, respectively), while T2 and T2+T3 irrigation strategies showed the lowest percentage (5-8%, respectively). Finally, the incidence of SBD was negatively correlated with the fruit dry matter (r=-0.88; P≤0.05).

Persimmon is a typical fruit crop of the Mediterranean region and, since it is considered a minor species, little information is available on its nutrients need. In the present experiment, it was estimated the quantity of removed and recycled nutrients by Kaki Tipo and Rojo Brillante, the two main varieties of persimmon grown in Emilia-Romagna region (Po Valley, Italy). Plants from ten mature orchards were selected and harvested; organs (leaves in summer, fruits at harvest, abscissed leaves, roots and skeleton) biomass and mineral composition were determined. The yearly uptake of macronutrients was similar for the 2 varieties, accounting for (kg ha−1): N 89-91, P 10-11, K 79-91, Ca 132-162, Mg 22-26 and S 9. While K was mostly found in fruits, Ca and Mg were mainly partitioned to leaves. Among micronutrients, Mn and Fe showed the highest values (1.1–1.3 and 1.2–2.1 kg ha−1, respectively), followed by B (370 g ha−1), while Cu and Zn showed the smallest amounts (less 100 g ha−1). Nitrogen, Ca, Mg and S were those more recycled than removed, while K showed an opposite trend; among the microelements, the annual recycled fractions of B and Mn were higher than that removed.

Wastewater may represent an alternative source for irrigation and mineral nutrients in intensive agriculture, offering potential agronomical and environmental advantages. This work investigates the effect of STW (secondary treated wastewater) used for irrigation, on the nutritional and physiological response of 3-year-old nectarine trees. To this end, trees ('Big Top'/'GF 677') were individually grown on 40-L pots filled with a sandy-loamy soil and drip irrigated with: a) Tap water (U) (unfertilized trees); b) Tap water (M) (mineral fertilized trees) and c) Secondary treated wastewater (W) (trees did not receive mineral fertilizers). Each treatment was applied to five individual trees. Regardless of the water source, trees received 360 L tree‑1 season‑1 and only M-trees received 14.2, 2.35, 8.96, and 0.72 g tree‑1 season‑1 of N, P, K and Mg, respectively, from commercial fertilizers throughout the season. Shoot length and photosynthetic daily assimilation rates were promoted by STW, compared to U trees, although M trees showed the highest values. This response is likely related to the amount of nutrients supplied to the trees along the season. Although STW provided a “fertigation-like” effect, results suggest that this strategy did not completely fulfill the tree nutrient demand. On the other hand, the STW recycling as irrigation water was not detrimental to plant growth. Treatments affected mainly leaf rather than fruit mineral concentration. Mineral concentration resulted mostly in the optimal range for all the treatments, except the U, which showed nutritional deficiencies. Heavy metal concentration both in leaves and fruit tissues was unaffected by treatments, with concentrations within international limits imposed for the human consumption. Results indicate how STW may be conveniently recycled as water source in the irrigation strategies of perennial species grown in temperate environments although this strategy may only contribute to partial fulfilment of plant nutrient requirements.

The intensification of highly specialized viticulture has led to a dramatic decrease of soil fertility that can be restored by increasing soil organic matter using organic fertilizers. The aim of the present experiment was to evaluate the effect of different organic amendments on vine vegetative growth and nutritional status, soil N availability and microbial biomass, as well as on yield and grape quality. The experiment was carried out in 2020 and 2021, on cv. Sangiovese (Vitis vinifera L.) vines grafted on 110 Richter (V. berlandieri × V. rupestris) planted in February 2019. Plants were fertilized yearly in spring with (1) mineral fertilization (MIN), (2) municipal organic waste compost (MOW), and (3) sewage sludge compost (SS). The application of SS increased nitrate availability in both years, while the supply of organic matter (no matter the source) enhanced soil microbial biomass content. Plant nutritional status was in the optimal range for all treatments, with an increase of N in SS and K in MOW. Fruit yield in 2020 was not influenced by treatments, while in 2021 it was enhanced by MIN and MOW, which also induced a higher berry quality. Plant vegetative growth was stimulated by the application of SS. In conclusion, from these preliminary results we observed a higher N availability as a consequence of SS supply that resulted in a higher plant biomass, but reduced yield and berry quality, supporting the theory that for vineyards, N should be carefully managed to reach an equilibrium between vegetative and reproductive activity.

The objective of this experiment was to valuate, after 14 years, the impact of annual compost applications on micronutrient and potentially toxic trace elements on nectarine tree uptake and soil fertility. The study was performed in the Po valley, Italy, on the variety Stark RedGold (grafted on GF677). Since orchard planting, the following treatments were applied, in a randomized complete block design, with four replicates: 1. unfertilized control; 2. mineral fertilization (N was supplied as NO3NH4 at 70–130 kg ha−1 year−1); 3. compost at 5 t DW ha−1 year−1; 4. compost at 10 t DW ha−1 year−1. The actual rate of application was 12.5 (LOW) and 25 (HIGH) t ha−1, since compost was concentrated in the tree row. Compost was made from domestic organic wastes mixed with pruning material from urban ornamental trees and garden management and stabilized for 3 months. The supply of compost HIGH induced an enrichment of soil total Cu, Zn and Cd, and a decrease of Fe and Co concentration; with values always below the European threshold limits for heavy metals in the soil. In addition, compost (at both rates) increased availability (DTPA-extractable) of Fe, Mn and Zn, Cd, Ni, and Pb in the top soil (0–0.15 m). Total micronutrient and trace element tree content was not affected by fertilization treatments; however, the recycled fraction returned to the soil at the end of the season through abscised leaves and pruned wood of Cu, Fe, Mn and Zn was increased by mineral fertilization; Fe and Zn also by compost HIGH. Our data show that the introduction of compost at both 12.5 and 25 t ha−1 year−1 in the row did not increase the risk of pollution related to potentially toxic trace elements and at the same time increased the bioavailability of Fe, Mn and Zn.

The aim of this study was to verify the influence of biofertilizer application resulting from energy production from corn biomass on nutrient uptake by pear plants during the growing cycle, and on fruit quality. The experiment was carried out on a Siltic Haplic Calcisol in the Italian province of Ferrara, in a medium-density Abbé Fétel commercial orchard. Treatments consisted of control (no application) and biofertilizer (30 m3 ha-1 biofertilizer application on the row), with four replicates. The following variables were evaluated: mineral N, microbial biomass and respiration in soil; nutrient content in leaves; and fruit quality. Biofertilizer application increased soil mineral N availability; soil microbial biomass and respiration, but the content of this nutrient did not increase in leaves. Leaf nutrient concentration varied during growth season and biofertilizer application increased potassium, phosphorus and zinc concentration in mature leaves and reduced leaf magnesium and manganese concentration. Biofertilizer application reduced fruit dry matter content, total soluble solids and boron concentration, with no effect on fruit firmness and titratable acidity. Biofertilizer application has positive effect on soil mineral N dynamics and soil microflora, altering the content of nutrients in leaves, favoring fruit production. Resumo O objetivo foi verificar a influência da aplicação de biofertilizante resultante da produção de energia a partir de biomassa de milho na absorção de nutrientes por plantas de pera durante o ciclo de cultivo, e na qualidade dos frutos. O experimento foi realizado em Ferrara (Itália), num pomar da cv. Abate Fétel, sobre Calcisolo Síltico Háplico. Os tratamentos consistiram em controle (sem aplicação) e biofertilizante (aplicação de 30 m3 ha-1 de biofertilizante, localizada na fila), com quatro repetições. Foram avaliados: N mineral, biomassa e respiração microbiana no solo; teor de nutrientes em folhas; e parâmetros de qualidade dos frutos. A aplicação de biofertilizante aumentou a disponibilidade de N mineral, a biomassa e respiração microbianas, e mesmo assim o teor deste nutriente não aumentou nas folhas. Os teores dos nutrientes foliares variaram durante a estação de crescimento e a aplicação de biofertilizante aumentou os teores de potássio, fósforo e zinco nas folhas maduras; enquanto reduziu o teor de magnésio e manganês foliar. A aplicação de biofertilizante reduziu o teor de massa seca, de sólidos totais e de boro dos frutos, sem efeito na firmeza e na acidez titulável. O biofertilizante teve efeito positivo sobre a dinâmica do N mineral no solo e a microbiota edáfica, alterando o teor de nutrientes nas folhas, favorecendo a produção de frutos.

The continuous use of copper (Cu)-based fungicides in viticulture to counteract fungal diseases has resulted in an accumulation of Cu in the topsoil, sometimes reaching toxic levels that can cause plant stress and reduce soil fertility. A possible strategy to mitigate the negative effects of Cu could include its incorporation into chemical compounds with phosphorous (P). The aim of this study was to evaluate the effectiveness of soil P addition on alleviating the toxic effect of Cu when applied in excess to potted grapevines plants. Micro-propagated plants of 1103 Paulsen rootstock were grown according to a factorial experimental design with two factors: Cu (4 levels: 0, 100, 200 and 300 mg kg-1 dw) and P (2 levels: 0 and 100 mg kg-1 dw) and three replicates. Sixty days after transplant, P was not effective in preventing the accumulation of Cu in vines. The total plant biomass was not influenced by soil Cu addition, while P increased plant growth by enhancing plant nutritional status. In addition, Cu reduced nutrient (P, K and Zn) content in plants. Net photosynthesis and efficiency of photosystem II decreased as a consequence of the increase of Cu concentration in soil. The effect of P in mitigating Cu toxicity was mainly related to the ability of plants to restore nutrient uptake.

The aim of the present study was to evaluate the effectiveness of P soil addition to mitigate the toxic effect of excess of Cu on grapevine on sandy non-calcareous soil. Micro-propagated plants of 1103 Paulsen rootstock were grown according to a factorial experimental design with two factors: Cu addition (0, 100, 200 and 300 mg kg −1 dw) and P addition (0, 50 and 100 mg kg −1 soil dw). The experiment was conducted in the greenhouse and plants were grown on a sandy soil in rhizoboxes. At the end of the trial, plants were destructively harvested, the biomass and the nutrient concentration of organs were determined. Root growth was evaluated during the trial and the concentration of organic acid in root tissue and exudates was determined. Shoot length and plant biomass declined as Cu concentration in soil increased; the application of P enhanced plant growth and nutritional status. Root biomass decreased at Cu > 100 mg kg −1 and increased in P at 100 mg kg −1 . Phosphorous stimulated root length, diameter and the number of apexes. Root citric acid increased as a response of Cu at 300 mg kg −1 , root ascorbic acid decreased with the increase of Cu (200 and 300 mg kg −1 ) and P at 100 mg kg −1 . The concentration of citric acid from root exudations was higher in Cu at 300 mg kg −1 and Cu at 200 mg kg −1 (compared to control) and P at 100 mg kg −1 soils. The application of P fertilization seems to be a valuable strategy to overcome the toxicity of high concentration of Cu in soil.

Objective In obstructive sleep apnea (OSA), while both hypothyroidism and hyperthyroidism have been studied, the occurrence of non-thyroidal illness syndrome (NTIS) (normal thyroid stimulating hormone [TSH] with low triiodotironine) has not been investigated. We explored the occurrence of NTIS in patients with moderate to severe OSA and its relationship to the severity of nocturnal respiratory disorders. We also studied the occurrence of subclinical hypothyroidism (SH, ie, high TSH with normal thyroxine) in OSA and changes in circulating TSH, free triiodotironine (fT3) and free thyroxine (fT4) after CPAP treatment. Methods After a nocturnal respiratory polysomnography, 125 consecutive patients with moderate to severe OSA and 60 control subjects with normal nocturnal respiration were recruited. Morning circulating TSH, fT3, and fT4 were measured in all subjects. In a subsample of patients, nocturnal polysomnography and hormonal determinations were repeated after CPAP treatment for five months. Results NTIS was found in 13 (10.4%), and SH in ten (8%) OSA subjects, but not in any control subjects. Patients with NTIS showed worse mean nocturnal oxygen saturation and time with saturation

The aim of the present investigation was to evaluate the effects of annual application of three rates of compost on nutrient concentration and accumulation in tree organs, after 11 years of continuous application of a municipal solid waste (MSW) compost in a commercial nectarine orchard. Trees were subjected, since their plantation (2001), to the following MSW compost rate: 0, 5 and 10 t dw ha−1 yr−1, split in May (60%) and September (40%). In 2011/2012 biomass of pruned wood, thinned fruits, fruit pulp and stones at harvest, and abscised leaves were weighted and analyzed for macro (N, P, K, Ca, Mg) and micro (Fe, Mn, Cu, and Zn) nutrients concentration. In addition, leaves and fruit pulp at harvest were analyzed for heavy metal (Cd, Cr, Hg and Pb) concentration. Plant part biomass (with the exception of thinned fruits) was linearly related to compost application rate. The highest rate of compost increased N and decreased Ca and Mg concentration in leaves sampled in summer, whereas no differences among treatments were observed for the other nutrients. At the end of the season leaf N, K and Zn were remobilized to storage plant part, while P, Ca, Mg, Fe and Mn reached the highest values in abscised leaves. Nitrogen, K, Mg, Cu, Mn and Zn accumulation in the plant part analyzed increased as a consequence of the application of compost at 10 t ha−1 when compared with compost at 5 t ha−1 and control. Phosphorous accumulation was increased by compost at the highest rate compared with control; no differences were observed for Ca and Fe accumulation. Nitrogen and P were mainly accumulated in fruit, abscised leaves and pruned wood; K was allocated mainly into fruits, while Ca and Mg were found highest in abscised leaves. Concentration of heavy metals in leaves and fruits were not affected by treatments.

We evaluated the effectiveness of soil and foliar applications of calcium chloride (CaCl2) on reducing pear susceptibility of brown spot (Stemphylium vesicarium). Two experiments were done using pear trees of the variety Abbé Fetel grafted on quince (Cydonia oblonga) rootstock. Potted trees were treated with soil and foliar application of CaCl2, while commercial trees were subjected only to soil application of 5.6 g CaCl2 L−1, and 11.2 g CaCl2 L−1. In a controlled environment, leaf and fruit brown spot incidence decreased with the increase of residual calcium (Ca) concentration in the tissue, according to a second degree function. In fruits from field experiment, disease symptoms were decreased by soil application of CaCl2 that increased Ca fruit concentration above 1000 mg kg−1 dw; however, no clear correlation between fruit Ca and brown spot incidence was found. Leaf water and osmotic potential were not related to brown spot incidence.

We assessed the effect of soil-applied fresh-ground fruits of melia (Melia azedarach L.) on N uptake for peach nutrition. Forty one-year-old 'Rome Star' peach trees (Prunus persica) grafted to GF677 peach x almond hybrid rootstock were planted in 20-L pots in April 2006. On 16 May, 20 pots were fertilized with compost at a rate of 100 g/pot and 20 pots were dressed with urea at 1.4 g/pot. On September 11, the two sets of trees received the same amount of N (0.64 g/pot) as urea (urea-treated pots) and blood meal (compost-treated pots). The following compounds were applied as nitrification inhibitors to 4 pots each: untreated control; 3,4-dimethylpyrazole phosphate (DMPP) at 10 mg/pot; commercial neem cake at 20 g kg -1 of soil; and fresh-ground fruits of melia at 20 and 40 g kg -1 of soil. All inhibitors were incorporated into the soil at planting except for DMPP, which was supplied along with the fertilizer (urea and compost/blood meal) applications. In our experimental conditions, all the nitrification inhibitors did not delay soil N mineralization, indeed the application of neem cake increased soil NO 3 - -N concentration in all sampling dates. An increase in leaf N concentration and microbial respiration was observed after application of neem cake and ground melia fruits at both concentrations, although only the latter increased shoot length.