Nutrient Balance Index Research Articles

Evaluation of oil palm (Elaeis guineensis Jacq.) productivity on peatlands based on DRIS analysis of leaf nutrient content in Siak District of Indonesia

Indonesia is the largest producer of oil palm in the world, with Riau Province particularly Siak District being the major contributor. The study focused on oil palm plantations within Siak District, characterized by a tropical rainforest climate of high humidity. The soil type in this area was a peatland with sapric and hemic maturity. The planting material used primarily consists of the DxP Marihat variety, which was planted between 1995-2005, with an average potential fresh fruit bunch productivity of 29.00 tons/ha/year. Variations in nutrient contents in oil palm leaf were observed across each block of the study location. Diagnosis and recommendation integrated system (DRIS) analysis was conducted on found number 17 to determine the key nutrients required to increase oil palm productivity. This method consists of several stages, including norm analysis, DRIS index, nutrient balance index (NBI), optimum leaf nutrient value, and leaf nutrient interval. Data was obtained from 312 leaf nutrient analyses and fresh fruit bunch productivity across 39 blocks for the period between 2015 and 2022. A value of 26.33 tons/ha/year, derived from DRIS norm calculation, indicated the border between high and low productivity blocks. The results showed that the order of macronutrient and micronutrient requirements in high productivity blocks was N>P>K>Ca>Mg and B>Cu>Zn, while in low productivity blocks, it was Ca>Mg>N>K>P and B>Cu>Zn. Regression of DRIS index and leaf nutrient content obtained optimum nutrient values of 2.78%, 0.16%, 1.02%, 0.66%, 0.35%, 29.51 ppm, 3.65 ppm, and 15.37 ppm for N, P, K, Ca, Mg, B, Cu, and Zn, respectively. Therefore, nutrients Ca and B were prioritized to increase the achievement of oil palm fresh fruit bunch productivity.

The DRIS methodology to determine the best balance of Nitrogen, phosphorus and potassium levels on the yield of Chickpea plant (Cicer arietinum L.)

This experiment was conducted during the spring growing season of 2020 conducted in the field at the Grdarasha farm field of Agricultural Engineering College, Salahaddin University in Erbil, located in the south of Erbil city, Latitude: 36.11284 N, Longitude: 44.01247 E. The soil texture class was silty clay loam, the type of soil vertisols, to study the effect of four levels of phosphorus TSP (0, 20, 40, 60) Kg P. ha-1,Three levels of K (0, 15, 30) Kg K. ha-1, and Three levels of N (0, 15, 30) Kg N. ha-1. There combination of yield components and nutrient balance of chickpea plants by using DRIS methodology, by using; split split block design with three factors (N, P, and K) 36 treatment with 3 replicates was used. The main results could be summarized as The combination between Nain plot potassium, Sub main plot nitrogen, and Sub sub main plot phosphorus levels affected the yield of the chickpea plant significant also the maximum yield was recorded in treatment combination (K2N1P2) was (1.55Mg ha-1). Whereas the lowest mean value (0.73Mg ha-1) was recorded from the treatment combination (K0N0P0). The combined effect of nitrogen, phosphorus and potassium fertilizer on nutrient balance indices (NBI) and yield in chickpea plants. The lowest nutrient balance index was recorded from the treatment combination (K2N1P2).

USE THE DRIS METHOD TO DETERMINE THE BEST NUTRIENTS BALANCE FOR CHICKPEA PLANTS THROUGH THE RELATIONSHIP BETWEEN NORMS AND CRITICAL POINT RATE

This study was aimed to determine the best nutrient balance for chickpeas from the relationship between the Norms of nutrients with the critical point for each nutrient using the DRIS system. This experiment was carried out at the Grdarasha farm, college of Agriculture Engineering Science, University of Salahaddin during the spring growing season of 2020, to find out the effects of three levels of nitrogen (UREA) (0, 15, 30 Kg N ha-1), four levels of triple super phosphate (0, 20, 40, 60 Kg P ha-1), and three levels of KCl fertilizer (0, 15, 30 Kg K ha-1) and their combination on Chickpea yield and nutrient balance by using Split Split plot design with three replicates. The highest yield (1.55 Mg ha-1) was recorded from the lowest (2.02) AT or NBI (nutrient balance index), while the lowest yield (0.73 Mg ha-1) was obtained from the highest AT value (62.68).

Continuous assessment of cowpea [Vigna unguiculata L. Walp.] nutritional status using diagnosis and recommendation integrated system approach

Cowpea is one of the widely cultivated and consumed grain legumes in Africa, but its production is hampered by soil fertility degradation on farms. Here, we assessed the spatial nutritional diagnosis of cowpea and the variability of their productivity using the diagnosis and recommendation integrated system (DRIS) and geostatistics tool. We achieved a sampling of 200 geo-referred points in cowpea farms in four communes of Benin. In addition, we determined grain yield and the content of N, P, K, Ca, Mg, and Zn in the leaves. From DRIS, the order of nutrient deficiency was as follows: P > K > Ca > Zn > N > Mg; P > K > Ca > N > Zn > Mg; N > Mg > Zn > K > P > Ca; P > Ca > K > N > Mg > Zn, at Dassa-Zoume, Glazoue, Ketou, and Ouesse, respectively. Sampling points were close enough to detect the spatial variability of the DRIS Index, mean of nutrient balance index (NBIm), and cowpea productivity (spatial dependence index ˃ 50%). The combined analysis of the cowpea relative yield and NBIm maps showed that the NBIm map effectively indicated the spatial distribution of cowpea productivity. The spatial variability of the DRIS index has provided an accurate guide to where adjustments to fertilization rates are needed.

Refined Evaluation of Soil Quality Sustainability in the Main Grain-Producing Areas of Heilongjiang Province

An evaluation of soil quality sustainability can support decision making for the sustainable use of land resources. However, certain current problems associated with these evaluations remain unaddressed, e.g., the evaluation indicators do not fully reflect soil quality risks and the evaluation scale is not sufficiently small. In this study, 25,000 spatial grids of dimensions 3 km × 3 km are used to divide the major grain-producing regions in China, namely, the Sanjiang Plain and the Songnen Plain of Heilongjiang. Then, the soil erosion modulus, nutrient balance index, soil organic carbon (SOC) storage, heavy metal soil pollution index and crop productivity are calculated for each grid using the RULSE model, nutrient balance index model, soil type method, geoaccumulation index method and mechanism method, respectively. A spatial grid cluster analysis method is used to thoroughly evaluate and analyze the sustainability of soil quality in each grid. The results show that the overall soil status of the study area is good. The soil and water conservation levels are high, the soils show low levels of contamination, the crop production potential is high and the ratio of highly sustainable to moderately sustainable soils is approximately 2:1. Only 2.74% of the land is rated extremely unsustainable and needs to be restored to a basic level of productivity before subsequent functional restoration can be carried out. This study provides a new method for the fine-scale evaluation of soil quality and contributes to the management of land resources.

(N.P.K) fertilizer application levels in Onion Crops and Using the Diagnosis and Recommendation Integrated System – DRIS

Fertilizations is one the efforts done to increase the production and quality of crops. Nitrogen, phosphorus and potassium fertilizers rate used in the production of Onion are excessive, so the essential elements present in the soil can be imbalanced ,nutrient balance determines crop yield and quality. This research aimed to evaluate Onion productivity subjected to various ratios of(NPK) to establish the DRIS-Norms and indexes, by using leaf nutrient analysis. The Diagnosis and Recommendation Integrated System-DRIS depended on interrelation between elements, compares crop mineral nutrient proportions with DRIS-norms (Optimal values) and we can know imbalances, deficiencies and excesses in nutrient of plants .The research was conducted in the experimental farm of college of agriculture ,university of Salahaddin in Grdarash field Erbil-Iraq,3.5Km to the south of Erbil city, (36° ON, 44° 01 E), (0411359, 03997002 UTM) ,planting date 30/1/2020 and harvesting at 30/6/2020 so the research period 5 months. We used spilt – spilt design in the experiment, first factor was Nitrogen (0, 40, 80, 160 Kg.ha-1), second factor was Phosphorus (0, 80, 160 Kg.ha-1) and the third factor was Potassium (0, 50, 100 Kg .ha-1) .The results indicated that the best fertilizer combinations that recorded highest Onion-Yield (18.36 Mg. ha-1) was(K 50 Kg. ha-1, P 160 Kg. ha-1, N 40 Kg. ha-1) which had lowest Nutrient Balance Index-(NBI), its values was (9.04) but the highest value was (73.18) for (K0P0N0) treatment.

DRIS Norms and Sufficiency Ranges for Persimmon ‘Rojo Brillante’ Grown under Mediterranean Conditions in Spain

The aim of this study was to establish DRIS (Diagnosis and Recommendation Integrated System) norms and Nutritional Optimal Ranges (NOR) for ‘Rojo Brillante’ Protected Designation of Origin (PDO) ‘Ribera del Xúquer’. The database contained 800 leaf samples collected in different crop phenological stages [after flowering (AF), fruit enlargement (FE), fruit colouring (FC), and harvesting HV)]. DRIS norms (78) were established for macronutrients: N, P, K, Ca, Mg and S; micronutrients B, Cu, Fe, Mn, and Zn and salinity elements: Na and Cl. The Nutrient Balance Index (NBI; the absolute value of the sum of the DRIS indices) was used to determine the optimal sampling period. Fruit enlargement was the period during which persimmon trees were more nutritionally balanced regardless of sprout origin (vegetative or floral) and irrigation type (drip or flood) in orchards

Comparison of the regional nutrient balance index by land and soil budget

Comparison of the regional nutrient balance index by land and soil budget

Nutritional balance and its relationship to yield in a coffee field: Inferences from geospatial analysis

ABSTRACT Information obtained from studies of spatial variability and the Diagnosis and Recommendation Integrated System (DRIS) may contribute to understanding better the relationship between mineral nutrient balance and factors that limit the crop yield. This study shows that nutritionally balanced plants may be associated with low productivity in Conilon coffee fields. The study was carried out on a highly productive Conilon coffee (Coffea canephora) field, in São Mateus, state of Espírito Santo, Brazil. A sample grid was established with 100 points, each point linked to one plant. Twenty pairs of leaves from each plant were collected from productive branches to create a sample for nutritional analysis. The rust incidence (Hemileia vastatrix), the presence of the coffee borer (Hypothenemus hampei), and the physical characteristics of the soil were evaluated in each sampled plant. DRIS and Nutrient Balance Index (NBI) were calculated, and from the yield data, they were characterized using descriptive statistics. Maps were created showing the spatial distribution of the NBI, yield, total sand, and incidence of rust and coffee borer. It was verified the low relationship between nutritional balance and yield in Conilon coffee, suggesting that non-nutritional factors also influenced plant production. In areas of the maps with high NBI, the plant’s nutritional balance was the main limiting factor of production, since most plants in this area produced less than the average productivity of the plants sampled. The use of a geostatistics tool combined with the NBI resulted in better understanding of the relationship between nutritional and non-nutritional variables on the Conilon coffee yield.

GROWTH AND NUTRITION OF Paratecoma peroba SEEDLINGS IN DIFFERENT TUBE VOLUMES AND CONTROLLED-RELEASE FERTILIZERS

Paratecoma peroba is a native forest species of great economic and ecological interest, currently at risk of extinction from selective and illegal exploitation; however, there are no established parameters for the production of seedlings of this species. The objective of this study was to analyze the growth and nutritional balance of P. peroba seedlings grown in polypropylene tubes of different sizes with variable doses of controlled-release fertilizer (CRF). Three volumes of tubes (120, 180, and 280 cm3), four CRF doses (0, 2.5, 5, and 7.5 kg m-3), and a conventional mineral fertilizer (CF) were tested as indicated in the literature for native forest species: arranged in a completely randomized design in a 3 × 5 factorial scheme, with four replicates composed of 16 seedlings. After 180 days, the percentage of survival, growth variables, indices of the diagnosis and recommendation integrated system, and the average nutrient balance index of the seedlings were analyzed. Based on the total dry matter and the mean nutritional balance index, the combination of a 280 cm³ tube with a 7.5 kg m-3 CRF dose was the most effective in the production of P. peroba seedlings.

Cover cropping system and mulching can shape soil microbial status in fruit orchards

ABSTRACT The use of cover crop in agricultural fields has been well elucidated, especially regarding nitrogen fixation from legume crops and their function as weed protection. Furthermore, to cover crops can benefit the soil microbial community. This study aimed to evaluate and compare the benefits of mulching and cover cropping systems on soil microbial growth and activity, and their effects on plant mineral nutrition in pomelo (Citrus maxima ) and macadamia ( Macadamia integrifolia ) orchards. The treatments included: 1) control [Glyphosate herbicide (Roundup at 4 l per ha)], 2) manual weed control, 3) mulching with dead leaves from their respective trees (macadamia and pomelo), 4) millet, 5) faba bean, 6) millet + faba bean. All the treatments were applied for 120 days before soil and plant leaves were sampled for analyses. Plant mineral nutrition, soil microbial biomass C (MBC) and soil microbial biomass N (MBN); basal respiration (BRA), arbuscular mycorrhizal fungi (AMF) colonization (COL); number of AMF spores (SPO) in soil; total organic carbon (TOC) and total nitrogen (TN) were evaluated. Plant nutrition was not altered by the treatments; however, the MBC, COL and SPO markedly increased in response to mulching and faba bean + millet treatments. Especially in macadamia soils, these treatments had a great response to soil microbiology. Significant negative correlations were also detected for the COL, SPO, BRA and TOC with the Nutrient Balance Index (NBI). These results indicate that in short-term the cover cropping system is useful to improve the soil microbial growth and AMF formation in soils of pomelo and macadam orchards.

Assessment of Nutrient Balance in Sugarcane Using DRIS and CND Methods

Many methods of nutritional diagnosis present discordant reports. It is necessary to study how these diagnoses relate to agricultural productivity and nutrient balance for a more efficient nutritional monitoring of the crops. This study had two objectives: (1) evaluate and compare Diagnosis and Recommendation Integrated System (DRIS) and Compositional Nutrient Diagnosis (CND) methods for nutritional diagnosis of sugarcane cultivated in the Northeast of Brazil; (2) establish standards, identify and hierarchize nutritional limitations. The database consisted of 183 samples, in which 31 were in areas with high productivity (³ 80 Mg ha-1) and 152 of areas with low productivity (< 80 Mg ha-1). Sugarcane leaves were collected and contents of N, P, K, Ca, Mg, S, Fe, Zn, Cu, Mn and B were determined. The DRIS indexes were calculated by methods DRIS-Beaufils, DRIS-Jones, DRIS-Elwali and Gascho, M-DRIS Beaufils, M-DRIS Jones, and the indexes CND too were calculated. The DRIS-Beaufils, DRIS-Jones, M-DRIS Beaufils and M-DRIS Jones methods tended to agree on the nutritional diagnosis of sugarcane. The nutritional diagnosis of the CND method interpreted by the Potencial Fertilization Response (PFR) was different from the DRIS methods for N and Mn nutrients. The M-DRIS Beaufils and M-DRIS Jones methods showed a higher correlation with nutrient contents. However, there was no significant correlation between agricultural productivity and nutrient balance index mean (NBIm), suggesting that other factors influenced sugarcane production more than nutritional factors. The nutritional diagnosis methods identified excessive fertilization with N and limitations of Ca, Mg, K, S, Mn, Cu, Zn and B in sugarcane in the Northeast of Brazil.

Cacao plantations on Sulawesi Island, Indonesia: I—an agro-ecological analysis of conventional and organic farms

The cacao plantation largely contributes to the Indonesian agricultural economy, and the systems with less environment impact have become fundamental for the local farmers. The current research made a general agro-ecological evaluation of six cacao farms in Sulawesi-Indonesia cultivated under conventional systems and organic management, here referred to as environmental friendly systems (EFS). Ten agro-ecological parameters, the number of fruits per area, the rate of infection (RI), number of seeds per fruit, and seed weight per fruit were evaluated. Furthermore, plant mineral nutrition was also analyzed, including the estimation of diagnosis recommendation integrated systems. The overall data indicated that RI in the conventional systems was lower than that in the EFS. The density of dead plant materials showed negative correlations with the area of weeds and density of weeds. The density of dead plant materials, concentrations of Mg and Fe showed a positive correlation with productivity. In addition, Fe showed negative correlations with weed area and density. The nutrient balance index also showed that in Parigi and Palolo areas, the plants were well stabled in terms of mineral nutrition. These results suggest that some agro-ecological parameters can function as cacao production indicators, especially the biomass and dead leaves together with plant mineral nutrition (Mg and Fe).

Nutritional diagnoses of oriental beech trees in damaged Caspian forest sites, using the diagnosis and recommendation integrated system (DRIS)

Oriental beech established in the Hyrcanian forests, is a valuable tree whose habitats are constantly exposed to destructive factors which change the nutritional status of soil and leaves. Analysis of foliar elements is a commonly used method for studying tree nutrient status that indicates site's quality. Foliar analysis of beech (Fagus orientalis Lipsky) was carried out in Kojour (Mazandaran) in order to assess the nutritional balance of trees in a damaged forest site (a direct result of livestock grazing and anthropogenic perturbations). Sunny leaves of dominant trees were taken in August and foliar concentration of macroelements, N, P, Ca, K and Mg were measured. The diagnosis and recommendation integrated system (DRIS) analysis was applied for evaluating the nutritional state. The results showed deficiency with K and P in disturbed stands. Nutrient Balance Index (NBI) indicated imbalance in nutrient status. These results suggest the usefulness of DRIS for foliar tissue analysis as an indicator of nutritional status and elemental stress in natural forests.

Crescimento e balanço nutricional de mudas de Enterolobium contortsiliquum com aplicação de substratos orgânicos e água residuária

Diante da geração acentuada de resíduos orgânicos sólidos e efluentes, a utilização desses materiais como fonte primária de nutrientes consiste em uma importante prática de gestão ambiental, sobretudo na produção de mudas com ênfase à recuperação de áreas degradadas. Objetivou-se com este trabalho avaliar o crescimento e o balanço nutricional de mudas de tamboril (Enterolobium contortsiliquum (Vell.) Morong) cultivadas em substratos com diferentes formulações e proporções de resíduos orgânicos irrigados com água residuária. Foram testados cinco proporções de composto orgânico e solo: 0:100; 20:80; 40:60; 60:40 e 80:20 v/v, e duas qualidades de água de irrigação: água de abastecimento e água residuária de suinocultura, dispostos em delineamento inteiramente casualizado em esquema fatorial, 5 x 2, com quatro repetições. Aos 90 dias, foram avaliadas as variáveis morfológicas, índices do sistema integrado de diagnose e recomendação e do balanço nutricional médio das mudas. Constatou-se que o resíduo orgânico contribui para o crescimento e o equilíbrio nutricional das mudas. A proporção 80:20 mostrou-se a mais indicada à produção de mudas de tamboril. O crescimento e balanço nutricional das mudas foram inferiores nos tratamentos que receberam irrigação com água residuária de suinocultura.Growth and nutrient balance of Enterolobium contortsiliquum seedlings with addition of organic substrates and wastewaterGiven the strong generation of solid organic waste and wastewater, the use of these materials as a primary source of nutrients is an important practice in environmental management, especially in the production of seedlings with emphasis on degraded areas. The objective of this study was to evaluate growth and nutrient balance of “tamboril” (Enterolobium contortsiliquum (Vell.) Morong) seedlings grown on substrates with different formulations proportions of organic matter irrigated with wastewater. It was tested five ratios of organic composts and soil: 0:100; 20:80; 40:60; 60:40 and 80:20 v/v. Two procedences of irrigation water was tested: water supply and wastewater from swine farming, arranged in a completely randomized design in a factorial scheme 5 x 2, with four replications. At 90 days, we evaluate seedlings morphological variables, the integrate diagnosis recommendation index and the nutrient balance index. The organic residue contributes to seedlings growth and nutritional balance. The proportion 80:20 proved to be the most suitable for “tamboril” seedlings production. Seedlings presented lower growth and nutritional balance when irrigate with swine farm wastewater.Index terms: “Bagana de carnaúba”; Bed aviary; Swine wastewater

NORMAS DRIS E NÍVEIS CRÍTICOS DE NUTRIENTES PARA VIDEIRA ‘NIAGARA ROSADA’ CULTIVADA NA REGIÃO DE JUNDIAÍ-SP

RESUMOSão apresentadas normas DRIS preliminares e derivados níveis críticos de nutrientes no tecido foliar (NC) para a videira ‘NiagaraRosada’ enxertada sobre o porta-enxerto ‘IAC 766’, nas condições de cultivo da região de Jundiaí-SP. As normas DRIS e os NCs foram obtidos a partir de um banco de dados com 116 registros, relacionando produtividade e teores foliares de N, P, K, Ca e Mg das videiras. Esses registros foram obtidos em experimentos de adubação e em um levantamento do estado nutricional de videiras realizados na região de Jundiaí, durante quatro ciclos de produção. Os registros foram separados em duas subpopulações: alto (>26 t/ha), e baixo rendimento (<26 t/ha) e as normas DRIS foram calculadas de acordo com os procedimentos convencionais. Mesmo com a diversidade nas condições de cultivo, a relação entre o índice de balanço nutricional e a produtividade das plantas foi altamente significativa (R2=0,48; p<0,0001), indicando que parte da variação na produtividade dos vinhedos pode ser creditada ao estado nutricional das plantas. Os NCs foram obtidos a partir de regressões múltiplas, relacionando teores foliares de cada nutriente com todos os índices DRIS. Os NCs para teores foliares de N, P, K, Ca e Mg foram 38,0; 3,0; 11,4; 13,7 e 3,5 g kg-1, respectivamente.

Diagnosis and recommendation integrated system (DRIS) of tomato in greenhouse

Plant nutrition is one of the most important factors for successful cultivation of tomatoes, especially in the greenhouse, and Diagnosis and Recommendation Integrated System (DRIS) is an alternative for fertilizer recommendation. This study aimed to establish DRIS norms for tomato plants growing in greenhouse located at Norte Pioneiro do Paraná region (Paraná State, Brazil). Chemical analysis of nutrients on leaves (N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn) of hybrid tomatoes (Colibri, Pizzadoro, Debora Max and Granadero), and respective yields of 61 growing areas in greenhouses (24.4 ha) were used. Samples were collected during April to December 2010, in five cities. Five levels of tomato yield (6, 7, 8, 9, and 10 kg plant-1) were used for establishing a database with all binary relationships among all the nutrients studied in all samples. The average, standard deviation and variance for each concentration of nutrient were calculated and it was done for relationship among nutrients, also, in each sub-population. We used 55 relationships which showed the highest ratio in the variance between sub-populations. The nutritional content of each nutrient and the nutrient balance index (IBN) of each production level were calculated. The best correlation between IBN and tomato yield was obtained with 8 kg plant-1 of tomato and this value was defined as an index to be used for DRIS. The nutritional diagnosis carried out in crops with yields below 6 kg plant-1 showed relative deficiencies of K and B and relative excess of Mg.

Influence of fungicides and vesicular arbuscular mycorrhiza on growth and nutrient balance of soybean by used DRIS equation

A pot experiment was conducted to study the effect of mycorrhiza, fungicides in difference concentration and there combination on growth and nutrients balance index of soya bean. Tow AM treatments including with and with out mycorrhiza and tow fungicides (parasmid and ant-arcol) each of them including four concentration (0.0, 0.25, 0.5 and 1 Kg·donum-1) were tested in factorial completely randomized design in the three replication. The results indicates that the higher value of total dry matter weight was recorded from combination treatment (F1M1C1) which attained 11.09 gm·pot-1 ,while the lower value 2.25 gm·pot-1 was produced by combination treatment (F2M2C3) ,however the same combination treatments was showed that the nitrogen ,phosphorus ,magnesium and iron in the shoot tissues in the mycorrhizal plant with lower concentration of fungicides were significantly greater (P -1, 251.00 mg·K-1) was recorded. The result of nutrient index and nutrient balance index revealed that the lower NBI (56.18) was recorded in combination treatments (F1M1C1), while the higher NBI (2033.81) was produced from combination treatments (F2M2C3), moreover the results shows significant negative correlation ship between NBI and total dry matter weight (r = -0.63*) .

Town-based spatial heterogeneity of nutrient balance and potential pollution risk of land application of animal manure and fertilizer in Shanghai, China

Land application of animal manure has been proven to be an efficient and convenient approach for animal manure treatment and resource recycling that has been encouraged in Shanghai suburbs in recent years. Based on livestock and poultry inventories, the available cropland base, and the application amounts of chemical fertilizer in each town of Shanghai, the nutrient supplies from animal manure, nutrient demands of croplands, and the nutrient inputs from chemical fertilizer were calculated. The nutrient balance and potential pollution risk of land application of animal manure and chemical fertilizer were evaluated by a calculated nutrient balance index (NBI) and nutrient pollution index (NPI). The results show that the annual total nitrogen (TN) demand of croplands was about 46,833 tons while the annual total phosphorus (TP) demand was around 11,373 tons. The annual TN supply from animal manure was 23,341 tons while the annual TP supply was 9,581 tons. The annual TN input from chemical fertilizer was 112,550 tons while the TP input was 14,782 tons. For land application of animal manure, more than 10% of all the towns had a NBI > 1 for TN, while more than 20% had a NBI > 1 for TP. For land application of chemical fertilizer, more than 80% of all the towns had a NBI > 1 for TN, while more than 60% had a NBI > 1 for TP. For the pollution risk of land application of animal manure and chemical fertilizer, there were more than 90% of all the towns with NPI > 1 for TN, while more than 80% with NPI > 1 for TP. For the entire city, the local croplands could agronomically use all the animal manure if it were properly distributed and applied reducing the need for large quantities of chemical fertilizer application.

Avaliação do estado nutricional de bananeiras do subgrupo Cavendish no estado de São Paulo: normas dris e níveis críticos de nutrientes

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; p<0,0001). O método para derivar os NCs a partir das normas DRIS foi eficiente, obtendo-se valores próximos daqueles citados na literatura, com exceção do NC para K, que, para as condições locais, foi inferior.