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Abstract This review focuses on the critical role of potassium (K) in potato cultivation, addressing its essential functions in plant metabolism and the challenges in managing soil K levels, specifically under sandy soils. The K use efficiency is higher in potatoes, with the maximum potential up to 55%, compared to cereals at 19%. Potatoes require high quantities of K, especially in well‐drained sandy soils, to maximise growth and yield. Because K is a highly leaching‐prone nutrient in these soils, its deficiencies could affect plant health, metabolism (K is required to activate more than 60 enzymes) and productivity. Optimal potato growth necessitates maintaining 1.8% K in the tubers, corresponding to a need of 0.22 kg K2O ac−1 for a substantial yield. The review article highlights the significant use of potash fertilisers in the United States, with an average consumption of 4.43 million metric tons between 2010 and 2021, underscoring the importance of K in agricultural practices. The paper also highlights the difference in K requirement and removal among different potato varieties that require the maximum amount in processing types. This manuscript discusses K's management schemes through soil testing, plant tissue analysis and artificial intelligence. The integration of various machine‐learning methods could offer promising prospects for predicting K response in potatoes, aiming to improve nutrient management and sustainable crop production. By synthesising current knowledge and advancements in K fertilisation techniques, this paper provides insights into overcoming the challenges of K management in potato cultivation, ultimately contributing to increased productivity and improved crop quality.

This dataset holds 9,175 entries that report the nitrogen, phosphorus, potassium, calcium, magnesium, zinc, manganese, copper and boron contents of various plant species, with a focus on crops. The dataset accounts data of 94 plant species, and present nutrient concentration of 14 different plant tissues. The data are derived from the Soil and Plant Nutrition Lab of the Chilean Agricultural Research Institute, which provided services to farmers in the Chilean Central Valley between 2006 and 2020. The analytical methods used to generate these data were consistent across all years, ensuring the reliability of the information. Specifically, nitrogen content was determined using the Kjeldahl method, while all other analytes were quantified via colorimetry (phosphorus and boron) or atomic absorption spectrometry following high-temperature oxidation and dilution of the ashes with hydrochloric acid. The dataset has numerous potential applications, including the estimation of crop nutrient extraction rates, the identification of nutrient deficiencies or excesses, and the provision of reference or prior information for researchers studying plant physiology. The dataset includes 21 Chilean endemic species, which might be of particular interest to researchers studying the biodiversity and ecology of Chile's Central Valley.

Significant losses in agricultural production are due to abiotic stresses, such as herbicide phytotoxicity. Dicamba (diglycolamine salt) is a herbicide used for post-emergent control of broadleaf weeds. It has a possibility to vapor-spread into neighboring fields causing damage to other crops. However, not every stress can be easily identified. Therefore, remote sensing has the potential as a new tool in early injury detection. This study evaluated the effects of simulated dicamba drift on the occurrence of phytotoxicity in soybeans (Glycine max). Soybean was assessed in seven dicamba doses (0, 0.056, 0.56, 5.6, 11.2, 28, 112 g ha−1) for changes in plant injury (scale of notes), spectral aspects (triangular greenness index (TGI), and shoot dry mass. The plants were photographed using a digital camera positioned at 1.2 m above the planting media level. The results indicate a positive effect of low dicamba doses (0.56 and 0.056 g a.e. ha−1) on TGI canopy distinction and shoot dry mass. Soybean TGI canopy distinction and the injury scale estimated at 45 days after sowing, and the soybean shoot dry mass observed at 99 days after sowing, presented significant and moderate Pearson’s r coefficient of correlations (r = −0.609 and 0.625), indicating TGI as a valid and practical spectral index for plant dicamba-injured evaluations.

The study presents the results of a three year field trial aimed at assessing the nutritional status of maize in critical growth stages by means of a plant analysis in the cultivation of three maize cultivars differing in their agronomic and genetic profile. The main research problem was to demonstrate whether the availability of nitrogen from stabilized fertilizers for "stay-green" maize varieties is consistent with the dynamics of the demand for this component. This is very important from both the economic and agronomic aspect of maize cultivation. The research showed a significant response of the maize cultivars to different nitrogen fertilizer formulations, which was observed in the period from the five-leaf stage to the full flowering stage. The advantage of the fertilizer, UltraGran stabilo, over other nitrogen fertilizers in the BBCH 15 stage was demonstrated only for the cultivar, ES Metronom, which produced a greater aerial mass while maintaining the nitrogen concentration at the level of the other two maize cultivars. The nitrogen and potassium content shaped the kernel weight in the ear in the flowering stage, confirming the importance of the interaction of these two elements in forming this feature of maize as the main predictor of the grain yield. This trait (expressed by the R2 coefficient) manifested each year of the study, but especially in the years with optimal weather patterns (i.e., the first year). The response of the maize cultivars to nitrogen fertilizers, especially the cultivar, ES Metronom, was manifested by an increase in the content of nutrients and chlorophyll in the ear leaf, that is considered a predictive organ for grain yield. The fertilizers, Super N-46 and UltraGran stabilo, had a positive effect on the chlorophyll content (CCI parameter) and increased its efficiency of excitation energy transfer (the F0 parameter). [ABSTRACT FROM AUTHOR]

Significant losses in agricultural production are due to abiotic stresses, such as herbicide phytotoxicity. Dicamba (diglycolamine salt) is a herbicide used for post-emergent control of broadleaf weeds. It has a possibility to vapor-spread into neighboring fields causing damage to other crops. However, not every stress can be easily identified. Therefore, remote sensing has the potential as a new tool in early injury detection. This study evaluated the effects of simulated dicamba drift on the occurrence of phytotoxicity in soybeans (Glycine max). Soybean was assessed in seven dicamba doses (0, 0.056, 0.56, 5.6, 11.2, 28, 112 g ha−1) for changes in plant injury (scale of notes), spectral aspects (triangular greenness index (TGI), and shoot dry mass. The plants were photographed using a digital camera positioned at 1.2 m above the planting media level. The results indicate a positive effect of low dicamba doses (0.56 and 0.056 g a.e. ha−1) on TGI canopy distinction and shoot dry mass. Soybean TGI canopy distinction and the injury scale estimated at 45 days after sowing, and the soybean shoot dry mass observed at 99 days after sowing, presented significant and moderate Pearson's r coefficient of correlations (r = −0.609 and 0.625), indicating TGI as a valid and practical spectral index for plant dicamba-injured evaluations. [ABSTRACT FROM AUTHOR]

Electrochemical sensors that can determine single/multiple analytes remain a key challenge in miniaturized analytical systems and devices. In this study, we present in situ synthesis and modification of gold nanodendrite electrodes to create an electrochemical system for the analysis of hydrogen peroxide. The sensor system consisted of the reference and counter electrodes as well as the working electrode. Electrochemical reduction of graphene oxide, ErGO, on the thin-film gold and gold nanodendrite working electrodes was used to achieve an efficient sensor interface for the adsorption of a biomimetic electrocatalytic sensor material, Mn(III) meso-tetra(N-methyl-4-pyridyl) porphyrin complex, with as high as 10–10 mol cm−2 surface coverage. The sensor system demonstrated a detection limit of 0.3 µM H2O2 in the presence of oxygen. Electrochemical determination of hydrogen peroxide in plant material in the concentration range from 0.09 to 0.4 µmol (gFW)−1 using the electrochemical sensor system was shown as well as in vivo real-time monitoring of the hydrogen peroxide dynamics as a sign of abiotic stress (intense sunlight). Results of the electrochemical determination were in good agreement with the results of biochemical analysis with the spectrophotometric detection. We anticipate that this method can be extended for the synthesis and integration of multisensor arrays in analytical microsystems and devices for the quantification and real-time in vivo monitoring of other analytes and biomarkers.

Among the different approaches currently being used to evaluate the contamination level of street dust, the magnetic susceptibility of dust and urban tree leaves has received little attention. The key objectives of this study were: (i) to investigate the feasibility of using pine needles as a bioindicator and biomagnetic indicator for estimating the concentration of selected metals in street dust, and (ii) to predict the contamination level of street dust by selected metals using magnetic susceptibility. Street dust and pine tree needle samples were taken from 60 locations in three adjacent cities in Kerman province (Kerman, Rafsanjan, and Sirjan), southeastern Iran. The total concentrations of selected metals, including Cu, Zn, Fe, Mn, Ni, and Pb, and the magnetic susceptibility (χ lf and χ hf) values of both pine tree needles and street dust samples were determined. Among the three cities studied, samples from Kerman showed the highest magnetic susceptibility and metal concentration values. This could be attributed to the larger size and much higher population density of this city, with more industrial activities and urban traffic than the other two cities investigated. The results also showed that the concentrations of metals in pine needles were strongly correlated (p < 0.01) with those in street dust. The magnetic susceptibility of pine needles and the concentrations of Fe, Pb, Zn, Cu, Ni, and Mn in street dust showed a statistically significant correlation (p < 0.01). A strong and statistically significant correlation (p < 0.01) was also found between magnetic susceptibility and the concentration of metals in pine needles. In conclusion, strong relationships between magnetic properties and metal concentrations of pine needles with those of street dust samples seem to make pine needles a good bioindicator and biomagnetic estimator of the contamination level of metals in street dust. [Display omitted] • Pine needles were found to be a good biomagnetic indicator of metal contamination in street dust. • The strong correlation between the concentration of metals of pine needles and street dust makes it a good bioindicator. • Pollution level of urban street dust can be estimated using its magnetic susceptibility. • Multivariate analysis revealed anthropogenic and/or natural sources of metals. • The population density influenced the magnetic susceptibility and metal concentration of street dust. [ABSTRACT FROM AUTHOR]

Monolithic fillings used in chromatography are of great interest among scientists since the first reports of their synthesis and use were published. In the 20 years since silica-based monolithic columns were introduced into the commercial market, numerous papers describing their chromatographical properties and utility in various branches of industry and scientific investigations were presented. This review is focused on possible applications of commercially available silica-based HPLC monolithic columns in the analysis of biological samples.

Trees as alive components of an ecosystem are able to convert some of the environment contaminants to unharmful substances and store some of them in their tissues and reduce their density and intensity in the air and soil by breath, root absorption and photosynthesis and other biotic functions. Trees function in such condition is completely related to environmental and habitat circumstances and their physiological potential. At beginning, five research sites at Khuzestan and Bushehr provinces were selected among the contaminated area by the Gulf War. At each site, soil sampling was made from three levels of depth (0-20, 20-40 and 40-60 cm). Soil physical and chemical characteristics test was made to measure nine metal elements and 12 other soil properties. The eucalypt species consisted of: E. camaldulensis, E. camaldulensis 9616, E. microtheca and E. sargentii which were planted under the Randomized Complete Blocks statistical design with three replicates. Before sampling the trees for determining the contaminant elements. Three individual trees were selected at each plot per one replicate to make sampling for leaf (four specimens per tree at four mean geographical directions). The data were analyzed under the variance analysis and Duncan test programs, using Excel and SAS computer soft wares. Overall, amount of the contaminants in different sites and at three levels of depth was not significantly different. The best eucalypt species and the best sites for absorbing the contaminants in their leaves are respectively as follows: 1- E. camaldulensis, E. microtheca, E. sargentii and E. camaldulensis 9616 2- Dezful, Isvand, Shooshtar, Karkheh and Kaki. The species which made the best performance in relation to their site interaction are respectively as follows: 1- E. microtheca firstly at Karkheh and shooshtar sites and secondly at Dezful and Isvand sites. 2- E. camaldulensis 9616 3- E. camaldulensis and E. sargentii.

The aim of this paper is to present the validation of inductively coupled plasma optical emission spectrometry (ICP-OES) method used for metals determination from several perennial plant samples. The suitability of two digestion procedures using wet digestion with mineral acids mixture on hot plate and microwave digestion was investigated to determine As, Cd, Cu, Fe, Mn, Pb and Zn in plants samples. The LOD of the seven analysed elements in solid samples varied between 0.20µg g-1 for Mn and 0.55µg g-1 for Pb. The found values for metals determined by ICP-OES in a vegetable certified reference material digested using the two procedures were compared with the certified values and good agreements between these values were obtained. The proposed method indicated satisfactory recovery, detection limits and standard deviations for trace metal determination in perennial plants samples.

Para estimativa da demanda de micronutrientes pela bananeira (Musa spp.) é fundamental que se conheçam as quantidades de matéria seca e de micronutrientes acumuladas na planta e exportadas pelo cacho. Neste trabalho, objetivou-se avaliar o acúmulo de matéria seca e de micronutrientes em seis variedades de bananeira sob irrigação. Foram amostradas plantas das variedades Grande Naine, Pacovan, Pacovan-Apodi, Prata-Anã, Terrinha e Gross Michel. As variedades foram plantadas em fileiras duplas, sendo 1.666 covas por hectare. Na época da colheita, foram escolhidas quatro touceiras de plantas de cada variedade para amostragem da planta-mãe, que foi dividida em rizoma, pseudocaule, pecíolo, limbo, engaço e frutos. Foram feitas pesagens para a determinação da matéria fresca de cada parte da planta-mãe de uma mesma touceira e retirada uma amostra de aproximadamente 700 g dessas partes para determinação do acúmulo de matéria seca e dos teores de micronutrientes. As amostras foram lavadas rapidamente com água de torneira, depois com água destilada e colocadas sobre as bancadas de uma casa de vegetação para pré-secagem. Posteriormente, foram colocadas em sacos de papel e levadas para uma estufa de circulação forçada de ar para obtenção do acúmulo de matéria seca e determinação dos teores de B, Cu, Fe, Mn e Zn. As variedades Pacovan, Prata Anã e Pacovan-Apodi acumularam maiores quantidades de matéria seca e de micronutrientes, quando comparadas com as variedades Grande Naine, Gross Michel e Terrinha, sendo a seguinte ordem decrescente de acúmulo e de exportação de micronutrientes: Mn > Fe > B > Zn > Cu.To estimate the demand of micronutrients for the banana plants (Musa spp.), it is essential to know the amounts of dry matter and micronutrients accumulated in the plant and exported by the bunch. The objective of this study was to evaluate the accumulation of dry matter and micronutrients by six banana varieties under irrigation. Plants of Grande Naine, Pacovan, Pacovan-Apodi, Prata-Anã, Terrinha and Gross Michel varieties grown in double rows, with a density equivalent to 1,666 plants per hectare were sampled. At harvest four plants of each variety were selected for sampling of mother-plant, which was divided into rhizome, pseudostem, petiole, leaf blade, stalk and fruits. The plant parts were weighed to determine the fresh weight of each part and a sample of about 700 g of each part was collected to determine dry weight and contents of micronutrients. The samples were washed quickly with tap water and later with distilled water and placed in a greenhouse for pre-drying and afterwards conditioned in paper bags were put in an oven of forced circulation of air for obtaining the dry matter and subsequent determination of the contents of B, Cu, Fe, Mn and Zn. The varieties Pacovan, Prata Anã e Pacovan Apodi accumulated greater amounts of dry matter and micronutrients, when compared to the varieties Grande Naine, Gross Michel e Terrinha, observing the following decreasing order of accumulation and export of micronutrients: Mn > Fe > B > Zn > Cu.

The experiment was carried out in the years 2002-2004. Its aim was the determination of the tendencies in the microelement nutritional status of the standard cultivars of Anthurium cultorum Birdsey (‘Baron’, ‘Choco’, ‘Midori’, ‘Pistache’, ‘President’, ‘Tropical’ from Anthura B.V.) in the autumn-winter and spring-summer vegetation periods. The plants were cultivated in expanded clay using a drop fertigation system with standard nutrition. A significant influence of the vegetation periods and the light conditions associated with them was found to be exerted on the microelement plant nutrition. In the autumn-winter period, characterized by light deficit, the plant age significantly modified the nutrition (increase or decrease of content with a plant’s aging) with regard to zinc (-23.7%), copper (-25.8%) and boron (+25%), while in the spring-summer period, iron (+12.9%) and copper (-21.7%) nutrition was modified. During the three years of the study, the autumnwinter period showed a significant increase of iron content (+9.8%) with a simultaneous decrease of copper content (-6.5%), in comparison with the springsummer period. The awareness of the cyclical nature of the changes in the nutritional status of plants, depending on the given vegetation season, supplies a valuable instrument in the interpretation of plant analyses for diagnostic purposes.

São apresentadas normas DRIS preliminares e derivados níveis críticos de nutrientes no tecido foliar (NC) para bananeiras do subgrupo Cavendish, nas condições de cultivo do Estado de São Paulo. As normas DRIS e os NCs foram obtidos a partir de um banco de dados com 188 registros, relacionando produtividade e teores foliares de N, P, K, Ca, Mg, B, Cu, Fe, Mn e Zn das cultivares Grande Naine e Nanicão. Esses registros foram extraídos de experimentos de adubação realizados no Planalto Paulista e no Vale do Ribeira, em áreas irrigadas e de sequeiro, durante cinco ciclos de cultivo, variando fontes e doses de fertilizantes. Mesmo com a grande diversidade nas condições de cultivo, a relação entre o índice de balanço nutricional e a produtividade das plantas foi altamente significativa (R²=0,60; pPreliminary DRIS norms and leaf nutrient critical levels (NCL) for Cavendish bananas growing in plantations of São Paulo State (Brazil) are presented. DRIS norms and NCL were established from a data bank of leaf nutrient concentration (N, P, K, Ca, Mg, B, Cu, Fe, Mn and Zn) and yield of banana with 188 samples. Data bank comprises information from plants of Grand Naine and Giant Cavendish growing in irrigated and non-irrigated areas, with different sources and rates of fertilizers during five crop cycles. Despite of the great diversity of cropping conditions, the regression between nutrient balance index and fruit yield was significant (R²=0.60; p

The American cranberry (Vaccinium macrocarpon Aiton) is an evergreen groundcover plant native to North America. Nowadays cranberries are successfully cultivated in Latvia with total plantings of more than 125 ha. Being a native wetland plant, cranberries are considered as nutrients low requiring crop, however, balanced mineral nutrition is one of the key factors that determine plant growth and yield development. Surveys were carried out to determine the actual status and trends in mineral nutrition of American cranberries in Latvia during 2005-2016. Together 190 plant samples were collected from different cranberry producing sites in Latvia over 3 periods: 2005-2007, 2008-2011 and 2012-2016. Cranberry tissue analyses were used as diagnostics method to control plant nutrient (N, P, K, Ca, Mg, S, Fe, Mn, Zn, Cu, Mo, B) status. The obtained results revealed notable nutrient imbalance in the years of the study. In general, our results suggest that only about 50% of plant tissue nutrient indices were in the sufficient range. Deficiency of N P, S, Fe, Cu, and Mo, and high levels of Mn was found in the majority of samples analyzed. In general, diverse tendencies were stated for the nutrient supply of cranberries from 2005 to 2016: positive trend in nutrient status of cranberry crop were found for N, K, Ca, while mean concentrations of S, Fe and Mo, as well as frequency of optimal indices decreased. The small count of nutrient indices in high till toxic range suggested on environmentally sound way of cranberry fertilization practices in Latvia. [ABSTRACT FROM AUTHOR]

Reliable plant analysis is a challenging task due to the physical character and chemical complexity of plant matrices. First of all, it requires the application of a proper sample preparation procedure to fully isolate the analyzed substances from the plant matrix. The high-temperature liquid-solid extraction is commonly applied for this purpose. In the light of recently published results, however, the application of high-temperature extraction for polyphenolics analysis in plants is disputable as it causes their transformation leading to erroneous quantitative estimations of these compounds. Experiments performed on different plants show that the transformation/degradation of quercetin and its glycosides is not induced by sea sand disruption method (SSDM) and prove the method to be most appropriate for the estimation of quercetin and its derivatives in plants. What is more, the application of SSDM in plant analysis allows the researcher, to determine which quercetin derivatives are native plant components and what is their true concentration. In other word, the application of SSDM in plant analysis eliminates errors in the study of plant metabolism involving quercetin and its derivatives. [ABSTRACT FROM AUTHOR]

Devido à falta de informações sobre adubação de coqueiro para o Estado de São Paulo, realizou-se um experimento de campo em Pereira Barreto (20º47'S; 51º01'W), visando a estudar os efeitos da aplicação de NPK em alguns atributos do solo e nutrição da planta, de set/2000 a fev/2004. O delineamento experimental foi em blocos ao acaso, no esquema fatorial fracionado 1/2(4³), com tratamentos constituídos pelas combinações de doses anuais de N (0; 120; 240 e 360 kg ha-1 de N), P (0; 100; 200 e 300 kg ha-1 de P2O5) e K (0; 120; 240 e 360 kg ha-1 de K2O). As doses de N, P e K foram aplicadas fracionadamente durante a estação das chuvas, empregando-se como fontes NH4NO3, superfosfato triplo e KCl, respectivamente. A aplicação de N em doses superiores a 240 kg ha-1 ano-1 causou excessiva acidificação do solo, sendo que 120 kg ha-1 ano-1 foi suficiente para manter o teor de N foliar na faixa de suficiência. A adubação com P e K nas doses mais elevadas resultou em perdas por lixiviação. A adubação com 120 kg ha-1 ano-1 de K2O foi suficiente para manter o teor de K do solo no mesmo nível da amostragem inicial e as plantas com teores de K foliar acima da faixa de suficiência. O P foliar manteve-se sempre acima da faixa de suficiência, independentemente da adubação fosfatada.There are very few information about fertilization of coconut grown in the State of São Paulo, Brazil. So a field experiment with 'Dwarf Green' coconut was carried out to study the effects of NPK rates on some soil chemical properties and plant nutrition, from September, 2000 to February, 2004. The trial was located on an Oxisol in the west part of the State of São Paulo (20º47'S; 51º01'W). The experimental design was an incomplete NPK factorial 1/2(4³). The treatments were annual rates of N (0, 120, 240, and 360 kg ha-1 of N), P (0, 100, 200, and 300 kg ha-1 of P2O5) and K (0, 120, 240, and 360 kg ha-1 of K2O), applied as NH4NO3, triple superphosphate and KCl, respectively. The rates of N, P e K were split during rainy season. Rates of N higher than 240 kg ha-1year-1 caused excessive soil acidification, whereas 120 kg ha-1year-1 was enough to achieve sufficiency range on leaves. Application of higher rates of P and K caused losses by leaching. It was necessary 120 kg of K2O ha-1year-1 to maintain soil exchangeable K at the same concentration as found prior to the experiment, the same rate kept leaf K concentration above sufficiency range. Foliar P contents were always higher than sufficiency range despite of P fertilization.

O teor de nitrato é um importante índice da qualidade dos alimentos, mas existem problemas na sua quantificação. O objetivo deste trabalho foi comparar procedimentos de quantificação de nitrato em tecido vegetal. Em amostras de matéria seca da parte aérea de três cultivares de alface adubadas com cinco doses de nitrogênio, provenientes de experimento realizado em casa de vegetação, foi feita extração de nitrato com água desionizada e quantificação, utilizando os procedimentos da coluna redutora contendo cádmio, da destilação, do ácido salicílico e da mistura redutora contendo zinco. Os procedimentos do ácido salicílico e da mistura redutora contendo zinco superestimam os teores de nitrato na matéria seca de alface, pois são mais sujeitos à presença de interferentes e ao efeito da cor do extrato. Os procedimentos da coluna redutora contendo cádmio e o da destilação são os mais adequados na quantificação de nitrato em tecido vegetal. Contudo, a simplicidade e o menor custo da destilação em relação à coluna redutora indicam que a destilação deve ser recomendada.Nitrate content determination is important for food quality evaluation, but its determination is affected by interferences. The objective of this work was to compare nitrate determination procedures for vegetable tissues. In dry matter samples from three lettuce cultivars that received five levels of nitrogen in a greenhouse experiment, nitrate was extracted with deionized water and its determination was made by the cadmium column method, the distillation method, the salicylic acid method, and the method using the reductive mixture with zinc. The salicylic acid method and that of reductive mixture with zinc overestimated the nitrate content in lettuce dry matter, because they were influenced by the color of dry matter extracts and other interferences. The cadmium column and the distillation methods are the best for nitrate determination in vegetable tissues, but the simplicity and lower cost of distillation in relation to cadmium column method suggest that the first one must be recommended.

O camu-camu [Myrciaria dubia (Humb., Bonpl. & Kunth) McVaugh], da família Myrtaceae, é encontrado em áreas inundáveis da Região Amazônica e utilizado como conservante em antioxidantes por seu alto teor de ácido ascórbico. O objetivo deste trabalho foi avaliar porta-enxertos desta família, adaptados a terra firme, visando à propagação vegetativa de camu-camu. Selecionaram-se duzentas e quarenta mudas de camu-camu, goiabeira (Psidium guajava L.) e pitangueira (Eugenia uniflora L.), que receberam quatro tipos de enxertia, originando doze tratamentos de sessenta plantas, com cinco repetições. Apenas o porta-enxerto de camu-camu se mostrou compatível. A incompatibilidade entre camu-camu e os porta-enxertos de goiabeira e pitangueira foi demonstrada por análises anatômicas.Camu-camu [Myrciaria dubia (Humb., Bonpl. & Kunth) McVaugh], of the Myrtaceaefamily, can be found at flooded areas in the Amazon region and it is used like a conservant in antioxidants due to its high ascorbic acid content. In order to obtain rootstocks of this family adapted to dry land for vegetative propagation of camu-camu, two hundred and forty plants of camu-camu, guava (Psidium guajava L.) and Surinam cherry (Eugenia uniflora L.) were selected. They received four different kinds of grafting, originating twelve treatments of sixty plants and five repetitions. Only the camu-camu rootstocks showed compatibility. Incompatibility between camu-camu and the rootstocks of guava and Surinam cherry was demonstrated by anatomical analysis.

The objectives of this study were to evaluate the relationship between the diagnosis and recommendation integrated system (DRIS) indices and foliar nutrient concentrations, to establish optimum foliar nutrient concentrations with DRIS and to validate the DRIS norms for sugarcane crop. Foliar nutrient concentrations from 126 sugarcane commercial fields were analyzed during the 1996/97 season, to calculate DRIS indices. Regression analysis was used to fit a model relating DRIS indices to nutrient concentrations. Experiments were carried out during the 1997/98 season, whose treatments consisted of the addition of the most limiting nutrients according to DRIS. A new diagnosis was performed. At the end of 1997/98 season, the yields of each plot were collected. Analysis of variance and Duncan test (5%) were used for the evaluation of the collected data. There was a positive and significant relationship between sugarcane foliar nutrient concentrations and DRIS indices. The optimum foliar nutrient concentrations for sugarcane are: 13.4 g ha-1 for N, 1.91 g ha-1 for P, 12.2 g ha-1 for K, 2.99 g ha-1 for Ca, 2.15 g ha-1 for Mg, 1.61 g ha-1 for S, 4.48 mg ha-1 for Cu, 67.8 mg ha-1 for Mnand 11.7 mg ha-1 for Zn. DRIS norms evaluated are useful to correct nutritional imbalances and to increase sugarcane yield.

The objectives of this study were to establish DRIS norms for sugarcane crop, to compare mean yield, foliar nutrient contents and variance of nutrient ratios of low- and high-yielding groups and to compare mean values of nutrient ratios selected as the DRIS norms of low- and high-yielding groups. Leaf samples (analyzed for N, P, K, Ca, Mg, S, Cu, Mn and Zn contents) and respective yields were collected in 126 commercial sugarcane fields in Rio de Janeiro State, Brazil and used to establish DRIS norms for sugarcane. Nearly all nutrient ratios selected as DRIS norms (77.8%) showed statistical differences between mean values of the low- and high-yielding groups. These different nutritional balances between the low- and high-yielding groups indicate that the DRIS norms developed in this paper are reliable. The DRIS norms for micronutrients with high S²l /S²h ratio and low coefficient of variation found can provide more security to evaluate the micronutrient status of sugarcane.

Enriched 10B (94.14 atom %) was supplied to coffee plantlets for three months. Then boron isotope ratios were determined in the leaf cell compartments, cell wall, nuclei and chloroplast, after a sub-cellular fractionation procedure. The isotopic measurements were performed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) provided with a direct injection nebulizer (DIN), introducing a sample volume of 50 muL. Isotopic ratios from 1.002 to 1.326 were determined with precision characterized by RSD lower than 1.5% for the enriched cell fractions with B concentrations ranging from 3.3 to 10.8 mug g-1. The detection limit (3sigma) was 0.5 ng B mL-1. The average enrichments in 10B atom % found in the cell walls, nuclei and chloroplasts were 46.7, 44.5 and 48.8, respectively.

High performance capillary electrophoresis (HPCE) on an uncoated fused-silica capillary column using a borate buffer at pH 9.2 as electrolyte and diode-array detection was developed for the determination of coumestrol in alfalfa. The linear detector response was established in the concentration range 0.76-140 mg.dm-3, the minimum detectable limit was 0.39 mg.dm-3, and migration time of coumestrol was 5 min. 3-Isobutyl-1-methylxanthin was used as an internal standard. Coumestrol was isolated by acid extraction employing a mixture hydrochloric acid-acetonitrile at 95°C for 30 min followed by solid phase extraction. Relative standard deviations of reproducibility and repeatability were 1.77% and 5.49%, respectively. Spiking recovery value of 92% was achieved. Alfalfa, variety Morava, contains 148-248 mg.kg-1 coumestrol in dry matter. The proposed method is useful for routine analyses.

The interaction of molybdenum (VI) with o-hydroxythiophenol derivatives (HTPDs) and aromatic amines (AAs) was studied. The following three HTPDs, which contain different halogen atoms at position 5, were used: 2-hydroxy-5-chlorothiophenol(HCTP), 2-hydroxy-5-bromothiophenol (HBTP), 2-hydroxy-5-iodothiophenol (HITP)]. The examined AAs were aniline (An), Nmethylaniline (mAn) and N,N-dimethylaniline (dAn). The obtained ternary complexes have a composition of 1:2:2 {Mo(V):HBTP:AA}.Optimal conditions for their liquid-liquid extraction (LLE) were found: organic solvent (chloroform), pH (4-6), concentration of the reagents ((1.3- 1.5)×10-3moldm-3 (HTPD) and (1.2-1.5) ×10-3moldm-3 (AA)) and extraction time(colour develops almost immediately after the reagents addition). The absorbance of the extracts is stable for at least 48 hours. The optimum shaking time is 10 min.). Under the optimal conditions, the complexes have absorption maxima (λmax) at 515-538 nm and molar absorptivities (εmax) between 3.1×104dm3mol-1 cm-1. The degrees of extraction were ⩾98.4%. The results suggested that linear relationships exist between the spectral characteristics (λmax or λmax) and some fundamental properties of the halogen substituent in the HTPD (atomic mass and electronegativity). The effect of foreign ions on the LLE-spectrophotometric determination of molybdenum was examined and two sensitive, selective and precise procedures for molybdenum determination were proposed. The relative standard deviations for Mo content of (3-5)×10-4 % were 4% (HCTP-An procedure) and 3% (HBTP-An procedure). [ABSTRACT FROM AUTHOR]

Fertigation with the nutrient solutions containing macro and microelements could influence on the nutrient status of highbush blueberry. Studies were conducted in the years 2002–2004 on a 10-year old plantation of highbush blueberry cv. ‘Bluecrop’. The aim was to analyze the effect of fertigation using 3 nutrient solutions (F-1, F-2, F-3) in comparison to drip irrigation (F-0) on the contents of macro- and microelements as well as sodium and aluminium in leaves. Fertigation with nutrient solutions F-1, F-2 and F-3 in relation to drip irrigation (F-0) increased the contents of nitrogen, potassium and calcium in the leaves of highbush blueberry cv. ‘Bluecrop’ at both terms of leaves collection (15.06 and 15.07) while it reduced the content of magnesium with the application of nutrient solutions F-2 and F-3 at the second term of study. No distinct effect of fertigation on the contents of phosphorus and sulphur in leaves was found. Among microelements the greatest effect of fertigation was indicated for boron. Nutrient solutions F-2 and F-3 at the first term as well as F-1, F-2 and F-3 at the second one increased boron content in leaves. Fertigation was found to have an effect on the increase of manganese and copper contents at the term II and zinc at the term I. No variation was recorded in iron content in leaves under the influence of fertigation. Fertigation reduced the content of aluminium in leaves of highbush blueberry. The effect was shown mainly under the influence of the application of nutrient solution F-2. Contents of N, P, K, Zn, Na and B decreased but Ca, Mg, Fe, Mn and Al increased in leaves between the first (15.06) and second II (15.07) term of study. No changes were found in contents of S or Cu in leaves of highbush blueberry at both sampling terms. For the evaluation of highbush blueberry nutrition status in Poland the term II seems to be more advantageous. It is the second half of July, after the first harvest of cv. „Bluecrop”. In this period there is the stabilization of vegetative growth with marked effects of bushes yielding.

Coconut is grown in more than 90 countries in the world and India occupies the third position with an area of 1.63 million hectares and a production of 12355 million nuts [Anon(a)1993‑94]. The crop makes a significant contribution to the national economy to the extent of Rs. 4,000 crores with an annual export earning of Rs. 126 crores [Anon (b) 1993‑94] per year which is much below its potential of more than 100 nuts per palm per year. Lack of adequate and proper management of nutrients is one of the reasons for this low productivity.

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The main aim of the study conducted in the years 2007–2008 was to evaluate the effect of increasing levels of N, P, K and Mg nutrition on contents of nutrients in leaves of lacy tree philodendron (Philodendron bipinnatifidum Schott et Endl.). Analyses were conducted for five levels of macroelement content in the substrate, while maintaining a constant quantitative ratio of N : P : K : Mg = 1.0 : 0.75 : 1.25 : 0.75. Levels of nutrients in the substrate were as follows (in mg·dm-3): L-1: N 100, P 75, K 125, Mg 75; L-2: N 150, P 112, K 187 Mg 112; L-3: N 200, P 150, K 250, Mg 150; L-4: N 250, P 187, K 312, Mg 187 and L-5: N 300, P 225, K 375, Mg 225, at the constant content of microelements (in mg·dm-3): Fe 75.0, Mn 25.0, Zn 20.0, Cu 10.0, B 1.5 and Mo 2.0. The third fully developed leaf, counting from the youngest leaf on a plant, was adopted as the index part for the evaluation of the nutrient status of plants. A significant effect of the substrate fertilization level was found on the contents of N, P, K, Fe, Mn, Zn and Cu in leaves. The date of sample collection in the vegetation period was also found to have an effect on the contents of N, P and K in leaves. It was shown that the age of plants had a significant effect on Ca content in leaves of lacy tree philodendron. Optimal yield of fresh and dry mass of aboveground parts of plants, as well as the number and length of leaves, width of leaf blades, length of petioles and leaf colour intensity was on the level of L-4, in which in the index part (the 3rd leaf) of lacy tree philodendron was: (% in d.m.): N 2.99–3.55, P 0.33–0.58, K 2.99–4.72, Ca 1.44–2.08, Mg 0.33–0.39; (mg·kg-1 d.m.): Fe 50.2–59.3, Mn 60.1–68.2, Zn 49.4–57.4, Cu 28.5–32.4.

The experiment was established in the spring 1999 on lessive soil developed from light boulder clay. Apple trees of Golden Delicious cv. on M.26 rootstock were planted in 3.5 × 1.2 m (2381 trees·ha-1) spacing. Research involved the effect of diversified levels of potassium fertilization: 12, 16 and 20 mg K 100 g-1 d.m. of soil and three types of potassium fertilizers: potassium chloride (KCl), potassium sulfate (K2SO4) and potassium nitrate (KNO3) on trees yielding and nutrition, as well as nutrient contents in the soil. Potassium fertilization using potassium chloride, potassium sulfate and potassium nitrate resulted in increased content of available potassium both in arable (0–20 cm) and in subarable (20–40 cm) layers of an apple orchard. Increase of available potassium content from 12 to 20 mg K·100 g-1 f. m of soil, due to fertilization with potassium chloride, potassium sulfate and potassium nitrate did increase soil pH (in H2O) in arable and subarable layers as a result of higher contents of available calcium. Alkalizing effect of potassium sulfate and potassium nitrate, generally assumed as physiologically acidifying, occurred on neutral and alkaline soils [pH (in H2O) over 6.90]. Fertilization with potassium chloride, potassium sulfate and potassium nitrate increased the content of sulfates in arable and subarable layers. The same result was observed in the case of chlorides in subarable layer. Application of potassium fertilization with potassium nitrate brought about decreased values of available magnesium content only in subarable layer. Due to the use of high rates of potassium nitrate, on the level 20 mg K·100 g-1 of soil, there was observed increased soil salinity (EC) both in arable and subarable layers. Introduction of potassium fertilization and increasingly higher rates of potassium fertilizers did not influence on the content of nitrogen, phosphorus, potassium, calcium, magnesium, sulfur and chlorine in apple tree leaves. Increasing potassium levels in the soil and potassium fertilizers did not affect the yield of Golden Delicious apple trees after coming them into full fruition period.

[Display omitted] • Experimental two-stage methanation plant with interstage cooling. • Simulation studies with 1D and 2D-reactor models. • CFD simulation for detection of maldistributions in first reactor stage. • Detailed investigation of the flexibility of the lab-scale methanation plant. • Wide operating window from 1.81 kW SNG to 9.08 kW SNG at stoichometric feed ratio. Hydrogen generated by power input from renewable energies can be produced in volatile patterns. Thus, methanation plants as part of Power-to-Gas processes using hydrogen as input stream are subject to high flexibility requirements. Flexibility of methanation plants is a growing topic, however, often limited to theoretical considerations and single reactors. Thus, in this study, we investigate the operating window of a lab-scale plant by means of experiment and simulation. Using experimental data of a two-stage plant, a plant model with detailed 1D reactor models is validated and the process is simulated. Comprehensive investigations are performed regarding operating parameters, such as plant load or coolant temperature. The operating window of the plant is investigated with focus on capacity and feedstock flexibility. A CFD simulation of the cooled fixed-bed reactor reveals insight in flow distribution and heat transfer. Results show a large operating window and thus a high flexibility of the plant. [ABSTRACT FROM AUTHOR]

Abstract: We present a very simple electrospray unit, a capillary spray cell, for easy analysis of small (10–50μL) sample aliquots. The sample, e.g., an unfiltered extract, is injected to a small sample cell, made of alumina and containing a short fused silica capillary mounted in its side. By the application of a 5kV potential between the sample cell and the entrance orifice of a mass spectrometer with an atmospheric pressure interface, the sample is dragged out of the cell at a rate of a few μL/min and an electrospray is generated at the tip of the silica capillary. The capillary spray cell benefits from a high internal diameter (up to 250μm) and very easy and inexpensive replacement of the capillary, which makes the sprayer well suited for analysis of unfiltered extracts. We demonstrate the direct analysis of extracts from plants and insects. In quantitative measurements using internal standards, a relatively high sensitivity (low ng/mL) is obtained together with good linearity (R 2 =0.998) in the range of 10–1000ng/mL. The capillary spray cell is also suited for use with field portable mass spectrometers, since no syringe pump or nebulizer gas is needed. Furthermore, the capillary spray cell is easily manufactured by most mechanical workshops. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present the validation of inductively coupled plasma optical emission spectrometry (ICP-OES) method used for metals determination from several perennial plant samples. The suitability of two digestion procedures using wet digestion with mineral acids mixture on hot plate and microwave digestion was investigated to determine As, Cd, Cu, Fe, Mn, Pb and Zn in plants samples. The LOD of the seven analysed elements in solid samples varied between 0.20μg g-1 for Mn and 0.55μg g-1 for Pb. The found values for metals determined by ICP-OES in a vegetable certified reference material digested using the two procedures were compared with the certified values and good agreements between these values were obtained. The proposed method indicated satisfactory recovery, detection limits and standard deviations for trace metal determination in perennial plants samples. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Elementology is the property of Journal of Elementology - issued by Polish Magnesium Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the introduction of nutrient management legislation in Ontario, there is a need to improve the efficiency of nitrogen (N) utilization. One possibility is to use critical nutrient concentrations in plant tissue as an indicator of the N nutritional status of the crop. Plant tissue analysis was used to determine the total N and nitrate-N (NO[sub3]-N) concentrations of cabbage (Brassica oleracea var. capitata L.), carrots (Daucus carota L.), and onions (Allium cepa L.) grown in Ontario. The tissue samples were collected from plants as part of N fertilization studies from 1999 to 2001 on the organic soils in the Holland/Bradford Marsh area and the mineral soils near Simcoe, Ontario. Yield was assessed at harvest as an indicator of the N requirement of the crop. Testing the usefulness of critical NO[sub3]-N concentrations to indicate the N requirement of the crop was problematic because: 1) few published references were available to indicate a critical level of NO[sub3]-N in these crops; 2) tissue NO[sub3]-N concentrations were highly variable; and 3) field data rarely matched published references. Tissue total N concentrations from the trials corresponded to published critical N concentrations in some cases, however, the use of published critical N concentrations would have resulted in either over or under-application of fertilizer to the crops. Cultivar, soil type, and climate were shown to affect tissue N concentrations. Based on these results it was concluded that local research and field verification is required before tissue N critical nutrient concentrations become useful for determining fertilizer needs of cabbage, carrots, and onions grown in Ontario. [ABSTRACT FROM AUTHOR]

The relationship between soil K supply, characterised by the soil solution K concentration and the soil K buffer power, and plant K status was investigated for field grown crops. The study was carried out in 15 K fertilisation trials with maize and wheat covering a wide range of agricultural soils and K level. Soil K buffer power was obtained through sorption–desorption curves. For each trial the critical K concentration in the soil solution was deduced from the relationship between the K concentration in the soil solution and the K concentration in shoot tissue water, which was considered as a relevant indicator of the plant K status. At sufficient K levels, the maximal K concentration in the shoot tissue water of maize (145 mM) was lower than that of wheat (175 mM) but the percentages of the critical K concentration in plant tissue water to this maximal K concentration were similar for the two plant species with an average of 75%. The critical K concentration in the soil solution varied between soils. However, a close correlation was found between the critical K concentration in soil solution and the inverse of the soil buffer power at this concentration (r2=0.981) or the inverse of the square of buffer power (r2=0.989). On a wide range of soils and field conditions, these two indicators were more able to account for K availability and plant response than exchangeable K content or K saturation ratio of the CEC. [ABSTRACT FROM AUTHOR]