Biochar in perennial crops: nutritional, agronomical and environmental implications

Biochar is the solid C-rich matrix obtained by pyrolysis of biomasses, currently promoted as a soil amendment with the aim to offset anthropogenic C emissions, while ameliorating soil properties and growth conditions. Benefits from biochar seem promising, although scientific understandings are beginning to be explored. In this project, I performed a suite of experiments in controlled and in field conditions with the aims to investigate the effect of biochar on: a) the interaction with minerals; b) Fe nutrition in kiwifruit; c) soil leaching, soil fertility, soil CO2 emissions partitioning, soil bacterial profile and key gene expression of soil nitrification-involved bacteria; d) plant growth, nutritional status, yield, fruit quality and e) its physical-chemical changes as affected by long-term environmental exposure. Biochar released K, P and Mg but retained Fe, Mn, Cu and Zn on its surface which in turn hindered Fe nutrition of kiwifruit trees. A redox reaction on the biochar surface exposed to a Fe source was elucidated. Biochar reduced the amount of leached NH4+-N but increased that of Hg, K, P, Mo, Se and Sn. Furthermore, biochar synergistically interacted with compost increasing soil field capacity, fertility, leaching of DOC, TDN and RSOC, suggesting a priming effect. However, in field conditions, biochar did not affect yield, nutritional status and fruit quality. Actinomadura flavalba, Saccharomonospora viridis, Thermosporomyces composti and Enterobacter spp. were peculiar of the soil amended with biochar plus compost which exhibited the highest band richness and promoted gene expression levels of Nitrosomonas spp., Nitrobacter spp. and enzymatic-related activity. Environmental exposure reduced C, K, pH and water infiltration of biochar which instead resulted in a higher O, Si, N, Na, Al, Ca, Mn and Fe at%. Oxidation occurred on the aged biochar surface, it decreased progressively with depth and induced the development of O-containing functional groups, up to 75nm depth

Evaluation of nutrients removed and recycled in a commercial peach orchard over a 14-years-production cycle

Understanding 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

Nutrient removal by apple, pear and cherry nursery trees

Given that nursery is a peculiar environment, the amount of nutrients removed by nursery trees represents a fundamental acquisition to optimize fertilization 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\uae; density of 40,000 trees ha-1) trees from a commercial nursery. Trees were divided into roots (below the root collar), rootstock (aboveground between root collar and grafting point) and variety (1-year old 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 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 aboveground rootstock. However, the dry biomass and nutrient amount measured in rootstocks (including roots) represent the cumulative amount of 2 and 3seasons, for Gisela\uae 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, correspondingto 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

Nutrição e manejo do solo em fruteiras de caroço em regiões de clima temperado

The agronomic techniques adopted for stone fruit trees cultivation should be ecologically and economically sustainable. This implies that production processes, apart from improving fruit yield and quality, mantain or increase the value of natural resources, guaranteeng satisfactory incomes to growers. The paper discusses fertilization and soil management aspects for peach, species largely investigated, and other stone fruit species, with emphasis on the Italian fruit industry. As técnicas adotadas no cultivo das frutas de caroço ou drupáceas devem ser definidas com uma visão de sustentabilidade ecológica e econômica. Tal visão sugere que os aspectos produtivos, voltados ao aumento da qualidade, sejam compatíveis com o ambiente, mantendo e, se possível, aumentando a qualidade dos recursos ambientais e garantindo, ao mesmo tempo, um adequado retorno econômico aos fruticultores. No presente trabalho são discutidos aspectos da fertilização e manejo do solo das drupáceas, assumindo como modelo o pessegueiro, espécie mais estudada, sendo evidenciados alguns resultados obtidos recentemente em outras espécies do grupo, com ênfase na Itália, mas que podem ser aplicados, na maioria dos casos, em qualquer situação

Nutrição e manejo do solo em fruteiras de caroço em regiões de clima temperado

The agronomic techniques adopted for stone fruit trees cultivation should be ecologically and economically sustainable. This implies that production processes, apart from improving fruit yield and quality, mantain or increase the value of natural resources, guaranteeng satisfactory incomes to growers. The paper discusses fertilization and soil management aspects for peach, species largely investigated, and other stone fruit species, with emphasis on the Italian fruit industry. As técnicas adotadas no cultivo das frutas de caroço ou drupáceas devem ser definidas com uma visão de sustentabilidade ecológica e econômica. Tal visão sugere que os aspectos produtivos, voltados ao aumento da qualidade, sejam compatíveis com o ambiente, mantendo e, se possível, aumentando a qualidade dos recursos ambientais e garantindo, ao mesmo tempo, um adequado retorno econômico aos fruticultores. No presente trabalho são discutidos aspectos da fertilização e manejo do solo das drupáceas, assumindo como modelo o pessegueiro, espécie mais estudada, sendo evidenciados alguns resultados obtidos recentemente em outras espécies do grupo, com ênfase na Itália, mas que podem ser aplicados, na maioria dos casos, em qualquer situação

Poda verde e produção do pessegueiro em alta densidade

O objetivo da pesquisa foi avaliar o efeito da poda verde em pessegueiros em alta densidade sobre a quantidade e qualidade de frutos produzidos nos anos agrícolas de 2010, 2011 e 2012 em Fazenda Rio Grande, Paraná. Os quatro tratamentos estudados foram: testemunha sem poda verde, uma poda verde realizada a 45 dias antes da colheita (AC), duas podas verdes a 45 e 75 dias AC e três podas verdes realizadas a 15, 45 e 75 dias AC. O método adotado para a poda verde foi a eliminação de ramos ladrões verticais e ramos voltados ao centro da copa e o desponte dos ramos acima de 2,3 m do solo. Foram avaliados a massa total colhida, a massa média do fruto, os diâmetros do fruto, a acidez titulável, o grau Brix, o pH e a relação Brix/Acidez. Não houve influência das diferentes épocas de poda verde em relação à produção de frutos por planta, ao tamanho do fruto e à qualidade química dos pêssegos colhidos, com exceção do pH do suco que aumentou ao longo das três safras analisadas. Concluiu-se que a poda verde realizada de 15 a 75 dias antes da colheita não influenciou na produção e na qualidade de pêssegos produzidos em alta densidade

O cultivo da macieira na Itália: porta-enxertos, cultivares, adubação e irrigação

A Itália é um dos principais países produtores de maçãs na Europa, destinada principalmente ao consumo in natura no mercado nacional e internacional. A produção e a qualidade dos frutos é dependente da cultivar, do porta-enxerto e das práticas de manejo, como a adubação e a irrigação adotado no pomar. Esta revisão tem por objetivo reportar as principais cultivares e porta-enxertos de macieira e o manejo da adubação e irrigação e suas atualizações em pomares de macieira da Itália. Os programas de melhoramento genético nesse país envolveram a seleção de cultivares e porta-enxertos de macieira que permitem a obtenção de altas produtividades e frutos de qualidade exigida pelo mercado consumidor. No manejo da adubação e irrigação, os nutrientes e a água têm sido fornecidos em quantidades próximas a real necessidade das plantas, proporcionando nutrição adequada, produção satisfatória e frutos de boa qualidade, além de evitar, sempre que possível, as perdas de nutrientes e água no ambiente

Use of compost to manage Fe nutrition of pear trees grown in calcareous soil

none3noThe aim of this study was to evaluate the effectiveness of soil applied compost in preventing Fe chlorosis of pear trees. The effect of the treatment was evaluated in field conditions on tree growth, nutritional status, yield, fruit quality and soil parameters. A 3-year long field trial was carried out in a mature commercial pear orchard of the cv. Abbé Fétel grafted on quince (Cydonia oblonga) BA29 located in the South Eastern Po Valley (Italy). In a completely randomized block design (5 replicates), including an untreated control, the following soil-applied treatments were compared: (i) Fe chelates (1.65 g Fe tree−1 year−1 as Fe–EDDHA) applied yearly and split in two applications in spring; (ii) organic amendment (compost) applied yearly at a rate of 12 kg fw tree−1 at bud break. Leaf Fe concentration and green color were increased by soil applied Fe chelate and, from the second season, by compost. Considering the whole experiment data of leaf Fe concentration and SPAD index showed a positive (P ≤ 0.001) linear correlation (r = 0.84). The supply of Fe chelate decreased significantly leaf K, Mn, fruit K and Cu concentration as well as fruit weight but raised tree yield. Compost showed intermediate values of tree crop load and higher fruit weight in comparison to Fe chelate. Iron deficiency reduced fruit sucrose and total carbohydrates concentration. Only compost addition stimulated soil microbial C biomass. Results demonstrate that composted organic wastes yearly applied improved Fe nutrition of pear trees grown in calcareous soils.noneG. SORRENTI; M. TOSELLI; B. MARANGONIG. SORRENTI; M. TOSELLI; B. MARANGON

Effect of organic fertilization on nutrient concentration and accumulation in nectarine (Prunus persica var. nucipersica) trees: the effect of rate of application

none5noThe aim of the present investigation was to evaluate the effects of annual application of three rates ofcompost on nutrient concentration and accumulation in tree organs, after 11 years of continuous applica-tion 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−1yr−1, split in May(60%) and September (40%). In 2011/2012 biomass of pruned wood, thinned fruits, fruit pulp and stonesat 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 forheavy 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 decreasedCa and Mg concentration in leaves sampled in summer, whereas no differences among treatments wereobserved for the other nutrients. At the end of the season leaf N, K and Zn were remobilized to storageplant 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 com-post at 10 t ha−1when compared with compost at 5 t ha−1and control. Phosphorous accumulation wasincreased by compost at the highest rate compared with control; no differences were observed for Ca andFe accumulation. Nitrogen and P were mainly accumulated in fruit, abscised leaves and pruned wood; Kwas allocated mainly into fruits, while Ca and Mg were found highest in abscised leaves. Concentrationof heavy metals in leaves and fruits were not affected by treatmentsmixedBALDI E.; MARCOLINI G.; QUARTIERI M.; SORRENTI G.; TOSELLI M.BALDI E.; MARCOLINI G.; QUARTIERI M.; SORRENTI G.; TOSELLI M