1,721,031 research outputs found
Evaluation of nutrients removed and recycled in a commercial peach orchard over a 14-years-production cycle
Full text linkUnderstanding nutrient dynamics within a peach orchard is fundamental to the development
of accurate nutrient management practices. The present study investigated the nutrient uptake and redistribution in a 14-years-old commercial orchard in the Po valley. At the end of the experiment, trees were
harvested, biomass and organ nutrient concentration were determined. Skeleton and roots accounted for
the highest plant biomass, followed by fruits at harvest, pruned wood and abscised leaves; thinned fruits
were less than 1 kg tree-1. The difference between the amounts of nutrients in leaves sampled in summer
and in autumn (at abscission) was used to estimate the fraction of nutrients remobilized during the vegetative season inside the tree. The decrease of N, P, S, Cu, Mn and Zn concentration in abscised, compared to summer-sampled leaves was the result of the translocation of nutrients into fruits and storage
organs. Nutrient circulation in a commercial nectarine orchard was calculated by determination of the
fractions of each nutrient recycled (sum of nutrients in abscised leaves, thinned fruits and pruned wood)
and remobilized (sum of nutrients in fruits at harvest, roots and skeleton). In our experimental conditions, on average, nectarine Stark RedGold showed an annual request of (in kg ha-1) 100, 17, 73, 129,
16, and 6 of N, P, K, Ca, Mg and S, respectively. More than half of these quantities were recycled in the
orchard and returned back to the soil; consequently, if the nutrient use efficiency is maximized, the fertilization of nectarine requires only small amount of external inputs
Effect of agro-industry by-products on soil fertility, tree performances and fruit quality in pear (Pyrus communis L.)
Full text linkOrganic materials from agro-industry processes can be used in agriculture as a way to recycle materials that still maintain a high fertilizing value. The aim of the experiment was to evaluate the value of soil applied apple juice by-product as fertilizer for pear trees. A 3-year experiment was carried out in a mature pear orchard (cv Abbé Fétel grafted onto quince MC) in the Po valley (Italy), where the following treatments were compared: 1) unfertilized control; 2) mineral N fertilization (60 kg N ha−1 year−1 split in two spring applications); 3) apple juice by-product (1.3 t ha−1 year−1, equal to 60 kg N ha−1), fully supplied at petal drop; 4) apple juice by-product, at twice the rate of the previous treatment. Apple juice by-product soil decomposition accounted for 12% in the first 6 months. At the end of the 24-month-assay, the decomposition accounted for 24% on total dry weight that makes 28% of initial C and 36% of initial N. Soil nitrate-N concentration was increased by the mineral N fertilizer, while the application of apple juice by-product increased microbial carbon. Tree growth, yield and fruit quality were not affected by treatments, while mineral N fertilization raised leaf and fruit N concentration. In conclusion, in our conditions the use of apple juice by-product did not show negative effects on tree performances and fruit quality, with some advantages related to the recycling of organic wastes in agriculture
Nutrient removal by apple, pear and cherry nursery trees
Full text linkGiven that nursery is a peculiar environment, the amount of nutrients removed by nursery trees represents a fundamental acquisition to optimise fertilisation strategies, with economic and environmental implications. In this context, we determined nutrient removal by apple, pear and cherry nursery trees at the end of the nursery growing cycle. We randomly removed 5 leafless apple (Golden Delicious/EMLA M9; density of 30,000 trees ha–1), pear (Santa Maria/Adams; density of 30,000 trees ha–1) and cherry (AlexTM/Gisela 6®; density of 40,000 trees ha–1) trees from a commercial nursery. Trees were divided into roots (below the root collar), rootstock (above-ground wood between root collar and grafting point) and variety (1-year-old wood above the grafting point). For each organ we determined biomass, macro- (N, P, K, Ca, Mg, S,) and micro- (Fe, Mn, Zn, Cu, and B) nutrient concentration. Pear trees were the most developed (650 g (dw) tree–1, equal to 1.75 and 2.78 folds than apple and cherry trees, respectively) whereas, independently of the species, variety mostly contributed (>50%) to the total tree biomass, followed by roots and then above-ground rootstock. However, the dry biomass and nutrient amount measured in rootstocks (including roots) represent the cumulative amount of 2 and 3 seasons, for Gisela® 6 (tissue culture) and pome fruit species (generated by mound layering), respectively. Macro and micronutrients were mostly concentrated in roots, followed by variety and rootstock, irrespective of the species. Independently of the tissue, macronutrients concentration hierarchy was N>Ca>K> P>Mg>S. Removed N by whole tree accounted for 6.58, 3.53 and 2.49 g tree–1 for pear, apple and cherry, respectively, corresponding to almost 200, 107 and 100 kg N ha–1, respectively. High amounts of K and Ca were used by pear (130-140 kg ha–1) and apple trees (~50 and 130 kg ha–1 of K and Ca, respectively), while ~25 kg K ha–1 and 55 kg Ca ha–1 were calculated for cherry nursery trees. Among micronutrients, Fe was the most required (~3 kg ha–1) independently of the species. B removal ranged between 1.2 and 2.4 kg ha–1 (80, 40 and 30 mg tree–1 for pear, apple and cherry, respectively), whereas Mn, Cu and Zn accounted for few hundred g ha–1, irrespective of the species. Given that nutrient concentration among tissues resulted within the same order of magnitude, irrespective of the species, differences in removal were mainly driven by the tree biomass as proved by the significant correlations between plant dry biomass with most of the nutrients we observed
Ten years of organic fertilization in peach: effect on soil fertility, tree nutritional status and fruit quality
No full textBeneficial effect of secondary treated wastewater irrigation on nectarine tree physiology
No full textIrrigation with secondary treated wastewater (STW) as a support to traditional irrigation management is becoming a necessary alternative to addressing issues of water shortage and fertilizer saving. The application of STW on young potted plants of Prunus persica (L.); cv: Big Top, grafted on GF 677, was studied outdoors on two consecutive seasons, during which three different irrigation treatments were compared: 1) irrigation with STW; 2) irrigation with tap water with the addition of mineral fertilizer (TW + MF) and 3) irrigation with tap water (TW). To assess the effects of the different irrigation treatments, tree nutritional status, shoot growth, Stem Cross Sectional Area (SCSA), Trunk Cross Sectional Area (TCSA), leaf gas exchanges, plant water status, fruit growth, fruit yield and quality were monitored during both seasons. Tree nutritional status, vegetative growth, TCSA, cumulative plant photosynthesis, fruit growth and yield were positively influenced by STW irrigation, compared to TW. TW + MF trees showed the highest vegetative growth and vegetative/reproductive ratio. This induced a rise in their water use and a consequent decrease in stem water potential, indicating the onset of water stress conditions. Results indicated that there was no negative effect of STW application on any of the monitored parameters. STW partially improved the plant physiological, nutritional and productive performances due to its intrinsic fertilizing effect. These results encourage further studies on the possibilities to directly use STW as an alternative source for irrigating and fertigating fruit crops even in open field conditions
Soil CO2 emission partitioning, bacterial community profile and gene expression of Nitrosomonas spp. and Nitrobacter spp. of a sandy soil amended with biochar and compost
No full textWe performed a 18-month experiment on 0.496 m3 pots filled with a sandy soil in which 1-year old nectarine trees were grown. With four replicates, the following amendment strategies were compared: a) unamended control; b) biochar (20 g fw kg−1); c) compost (76.8 g fw kg−1) and d) biocompost (mixing biochar and compost at the same rates of the previous two strategies). Amendments were applied at planting and only unamended and merely biochar-amended soils were fertilized with mineral inputs. Soil mineral N availability was regularly measured and at the end of the experiment, we determined total C and N concentration of soils and aged biochar fragments. Total soil respiration (RTOT) was separated into soil organic-C derived (RSOC) and rhizosphere (RR) respiration by the trenching method. Total soil DNA was extracted from samples collected after 6 and 18 months and bacterial community analysis was carried out by denaturing gradient gel electrophoresis (DGGE). Expression of nitrification key genes of ammonia monooxygenase (AMO) and nitrite oxidoreductase (NOR) and the relative abundance of specific bacterial community (Nitrosomonas spp. and Nitrobacter spp.) were determined by Real Time PCR on soil samples collected at 6, 12, 15, 16 and 18 months since amendments incorporation. The addition of compost significantly promoted soil mineral N, bacterial diversity and the relative expression of nitrification process related key genes. Furthermore, compost enhanced RSOC likely due to the stimulation of the microbial community by providing labile C sources. Conversely, changes due to the mere addition of biochar were negligible. However, biochar had no detrimental effects, rather it promoted gene expression involved in the nitrification process. A synergic effect between the two amendments emerged in the total soil C and N concentration and in the RSOC, leading to a significantly higher cumulative CO2. Although the source of the additional CO2 rate remains uncertain, a priming effect induced by biochar on the labile compost-derived C-fractions is hypothesized. Compost reduced the relative richness of Arthrobacter spp. in soil, while Actinomadura flavalba, Saccharomonospora viridis, Thermosporomyces composti and Enterobacter spp. were peculiar of the biocompost profile which increased band richness. Biocompost significantly increased the relative abundance of Nitrosomonas spp. and Nitrobacter spp. and both AMO and NOR key genes expression levels. The mixture of biochar and compost seems effective to induce agronomical benefits, although environmental concerns (e.g. additional CO2 emissions) require further investigations
Organic fertilization in nectarine (Prunus persica var. nucipersica) orchard combines nutrient management and pollution impact
No full textRecycled organic fertilizers may be used to replace chemical source of nutrients; however, some nutrients such as nitrogen and heavy metals
released by mineralization can become potential pollutants. The objective of this experiment was to compare, over a 3-year-period of time, the effectiveness of two organic fertilizers (cow manure and compost) with a traditional mineral fertilizer on soil fertility, tree nutritional status, heavy metal concentration in soil and plant in a mature nectarine orchard. Trees were subjected, since their plantation (made in 2001) to the following treatments: (1) mineral fertilization (including nitrogen at 130 kg ha-1 year-1); (2) cow manure (5 t DW year-1 ha-1); (3) compost (5 t DW year-1 ha-1). Soil organic matter and total nitrogen concentration increased as a consequence of compost application. Soil nitrate concentration was
increased by mineral fertilizer and compost applications. In summer, macro and micro nutrient concentrations in leaves were not affected by treatments with the exception of N that was increased by mineral fertilization. At the end of the season, leaf N, K and Zn were remobilized to storage organs, while Ca, Mg, Cu, Fe and Mn accumulated in abscised leaves and returned to the soil, with no differences among treatments. Nitrogen and K were found principally in fruit flesh. With the exception of Cu and Zn, the concentration of heavy metals in leaves and fruits was
below detection limits. Total and DTPA-extractable heavy metals in soil were not increased by organic fertilization if compared with mineral
fertilize
Effect of time of application on nitrogen uptake, partitioning, and remobilization in walnut trees
No full textWalnut tree requires a relatively high amount of nitrogen (N). To avoid loss in the environment, N uptake efficiency (NUE) should be optimized. The aims of this study were to evaluate the effect of time of N application on NUE, partitioning, and remobilization in walnut trees. Two-year-old trees were planted in 40-L pots and fertilized with 1 g of 15N-enriched (5 atom %) N at: 1) bud burst, 2) pistillate flower maturity, and 3) late summer. One week after fertilization, the percentage of N derived from fertilizer and NUE were higher in trees fertilized in late summer, than other timings. N uptake was linearly related to root dry weight. At May 2008 harvest, the N stored in trunk and twigs was remobilized to the developing leaves and to the roots. Late summer N application appeared to be the most effective in providing N for walnut spring new growth
Nocicoltura da frutto: Innovazione e Sostenibilità. Atti delle Giornate tecniche nazionali SOI NOCE 2019
Full text linkIl volume contiene gli atti del convegno: Nocicoltura da frutto: Innovazione e Sostenibilità. Giornate tecniche nazionali SOI NOCE 2019, svoltesi a Bologna presso il Dipartimento di Scienze e Tecnologie Agro-Alimentari dell'Università di Bologna, 20-21 settembre 2019
Nocicoltura da frutto: Innovazione e Sostenibilità. Atti delle Giornate tecniche nazionali SOI NOCE 2019
Full text linkIl volume contiene gli atti del convegno: Nocicoltura da frutto: Innovazione e Sostenibilità. Giornate tecniche nazionali SOI NOCE 2019, svoltesi a Bologna presso il Dipartimento di Scienze e Tecnologie Agro-Alimentari dell'Università di Bologna, 20-21 settembre 2019
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