ABSTRACT Integrated agricultural production systems have been improved with the introduction of Urochloa grasses aiming at obtaining straw for a no-tillage system (NTS) and the increase of legumes, which promote physicochemical improvements in soils and guarantee intensification and sustainability of production. This study aimed to evaluate the agronomic traits and yield of soybean in succession to the intercropping of corn with marandu grass and/or pigeonpea in five populations of plants harvested for silage production. The experiment was carried out in the Cerrado region of Selvíria, MS, Brazil, during the 2016/17 and 2017/18 agricultural years, in an Oxisol. The experimental design consisted of randomized blocks, with four replications. The treatments were arranged in a 2×5 factorial scheme, consisting of off-season corn intercropped with pigeonpea (Cajanus cajan (L.) Millsp.) and off-season corn intercropped with marandu grass (Urochloa brizantha) and pigeonpea, in addition to five sowing densities (0, 6, 12, 18, and 24 seeds m-1). Soybean was planted in succession aiming to evaluate the effect of remaining straw on crop performance. Soybean grown in succession to the triple intercropping of corn with marandu and pigeon pea shows increased productivity.

ABSTRACT The objective of this work was to evaluate the management of nitrogen fertilization in grains of sorghum inoculated or not with Azospirillum brasilense in single crop or intercropped with Urochloa brizantha (cv. Paiaguás) in the off-season. The experimental design was a completely randomized block design with four replications, in a 2 x 2 x 3 factorial scheme, with sorghum in single-cropped system or intercropped with grass; sorghum seeds inoculated or not with A. brasilense; and N management (application of 100% of the dose at sowing or only in topdressing or split - 30% at sowing and 70% in topdressing) at a dose of 120 kg ha-1 N. Morphological components and sorghum grain yield and productivity of dry matter of the aerial part of the grass and the sorghum were evaluated. The splitting of nitrogen fertilization did not interfere in the yield of sorghum grain straw intercropped with U. brizantha. The intercropping with U. brizantha did not reduce sorghum grain yield. In dry climate conditions in the off-season, inoculation of sorghum seeds cv. Ranchero with A. brasilense increases grain yield.

ABSTRACT One of the alternatives to achieve agriculture with sustainability and reduction in production costs, mainly with fertilizers, is the formation of straw from the previous crop and the use of genus Azospirillum bacteria. The objective of this study was to evaluate the agronomic characteristics and yield of soybean, cultivated in areas under straw of sorghum regrowth inoculated or not with diazotrophic bacteria, single or intercropped with Paiaguás grass under Integrated System of Agricultural Production, in Cerrado region. It was used a complete randomized block design, in a 2 x 2 x 2 factorial arrangement, with four replications, in two agricultural years: with the cultivation of dual-purpose and grain sorghum, single or intercropped with Paiaguás grass, with or without inoculating sorghum seeds with the bacterium Azospirillum brasilense. Soybean production and yield components were evaluated. Inoculation of grain or dual-purpose sorghum seeds with Azospirillum brasilense intercropped with Paiaguás grass, before soybean cultivation, increased the components of production and grain yield of soybean in succession.

RESUMO O desempenho da pecuária no Cerrado brasileiro tem sido limitado pela baixa disponibilidade de forragens de satisfatória qualidade, principalmente nos períodos de baixa precipitação pluvial. Objetivou-se avaliar o crescimento e a produtividade de massa seca de duas cultivares de sorgos inoculadas ou não com bactérias diazotróficas, exclusivamente ou em consórcio com capim-paiaguás, sob sistema de integração lavoura-pecuária, no período de outono-inverno, em região de Cerrado por dois anos agrícolas. Os experimentos foram realizados a campo, nos anos de 2015 e 2016, na fazenda experimental da Faculdade de Engenharia de Ilha Solteira, Unesp, em Selvíria-MS. O delineamento utilizado foi o de blocos casualizados, em esquema fatorial 2 x 2 x 2, com quatro repetições. Os tratamentos corresponderam: a dois anos agrícolas (2015 e 2016); cultivo de sorgo granífero e de dupla aptidão solteiros ou em consórcio com o capim-paiaguás, com ou sem a inoculação das sementes de sorgos com a bactéria Azospirillum brasilense. Avaliou-se a produtividade de massa seca dos componentes vegetais e o crescimento das plantas para confecção de silagem. A inoculação de sementes de sorgos com a bactéria Azospirillum brasilense aumenta a produção de massa seca vegetal para ensilagem, independentemente da cultivar ou consórcio com capim. A consorciação do sorgo granífero e dupla aptidão com o capim-paiaguás é um sistema viável do ponto de vista agronômico para produção de massa vegetal para ensilagem em cultivo outonal.

ABSTRACT Livestock performance in the Brazilian Cerrado has been limited by the low availability of good quality fodder, especially during periods of low rainfall. The aim of this study was to evaluate growth and dry matter production in two cultivars of sorghum, inoculated or not with diazotrophic bacteria, and as a monocrop or intercropped with palisade grass under a system of crop-livestock integration. The experiments were carried out in the field in the Cerrado region during the autumn-winter period of 2015 and 2016, on the experimental farm of the Faculty of Engineering at Ilha Solteira, UNESP, in Selvíria, in the State of Mato Groso do Sul, Brazil (MS). A randomised complete block experimental design was used in a 2 x 2 x 2 factorial scheme with four replications. The treatments corresponded to two agricultural years (2015 and 2016); the cultivation of dual-purpose grain sorghum, alone or intercropped with palisade grass; with or without inoculation of the sorghum seeds with the bacterium Azospirillum brasilense. The dry matter production of the plant components and plant growth were evaluated for the preparation of silage. Inoculation of sorghum seeds with the bacterium Azospirillum brasilense increases the production of plant dry matter for silage, irrespective of the cultivar or intercrop. Dual-purpose grain sorghum intercropped with palisade grass is a viable agronomic system for producing plant matter for silage during the autumn season.

Resumo: O objetivo deste trabalho foi determinar a opção economicamente mais viável do sistema de integração lavoura-pecuária em plantio direto, com sorgo consorciado com forrageiras tropicais ou guandu-anão, sucedido por soja ou milho, pelo período de dois anos. O experimento foi realizado em delineamento de blocos ao acaso, com quatro repetições. Os tratamentos consistiram de sorgo-forrageiro consorciado com: capim 'Marandu'; capim 'Marandu' e guandu-anão; capim 'Mombaça'; capim 'Mombaça' e guandu-anão; e guandu-anão e sorgo solteiro, colhidos para silagem no primeiro corte e na rebrota, sucedidos por soja ou milho. Os seguintes cálculos foram feitos: custo operacional efetivo, custo operacional total, receita bruta, lucro operacional, índice de lucratividade, preço de equilíbrio e produtividade de equilíbrio. Estas variáveis foram determinadas para as culturas individuais e para a soma das culturas que ocuparam a mesma área ao longo do tempo. Os consórcios de sorgo com capim 'Mombaça', com ou sem guandu-anão, apresentaram produtividade e lucratividade, respectivamente, 18 e 44% menores do que os consórcios de sorgo com capim 'Marandu', com ou sem guandu-anão. A soja em sucessão demanda menor controle químico do cultivo antecedente de capim 'Mombaça' que o milho em sucessão.

Abstract: The objective of this work was to determine the most economically viable integrated no-tillage crop-livestock system by intercropping sorghum with tropical forages or dwarf pigeon pea, succeeded by soybean or corn, over a two-year period. The experiment was carried out in a randomized complete block design with four replicates. The treatments consisted of forage sorghum intercropped with: 'Marandu' grass; 'Marandu' grass and dwarf pigeon pea; 'Mombaça' grass; 'Mombaça' grass and dwarf pigeon pea; and dwarf pigeon pea and single sorghum, harvested for silage in the first cut and regrowth, succeeded by soybean or corn. The following calculations were made: effective operational cost, total operational costs, gross revenues, operational income, profitability index, equilibrium price, and equilibrium productivity. These variables were determined for individual crops, as well as for the sum of the crops occupying the same area over time. The sorghum consortia with 'Mombaça' grass, with or without dwarf pigeon pea, had 18 and 14% lower productivity and profitability, respectively, than the sorghum consortia with 'Marandu' grass, with or without dwarf pigeon pea. Soybean in succession requires less chemical control of the 'Mombaça' grass than corn in succession.

ABSTRACT Soil fertility evaluation through soil analysis traditionally does not consider interaction among elements. To include the interaction effect in interpretation of soil analyses, an experiment was conducted to evaluate the effect of nitrogen fertilization (0, 0.5, 1.0, and 2.0 kg N per plant per cycle) with urea (45 % N) and potassium fertilization (0, 0.55, 1.1, and 2.2 kg K2O per plant per cycle) with potassium chloride (60 % K2O) on soil cationic balance. The experiment was carried out in an irrigated commercial production area of ‘Paluma’ guava, for five consecutive cycles, 2009 through 2012, using the concept of isometric log ratio (ilr) to evaluate soil cationic balance through [K, Ca, Mg | H+Al], [K | Ca, Mg] and [Ca | Mg] balances. The compositional data analysis showed to be a suitable tool to interpret the soil cationic balance given that the soil cationic balances value was changed by nitrogen fertilization and potassium as well as the soil pH value and the concentration of K in the soil. The soil cationic balances also changed by the variations of in climate conditions at period of soil sample. An application rate of 0.55 kg K2O per plant per cycle was considered sufficient to keep K soil concentration above 1.6 mmolc dm-3.

ABSTRACT Guava response to fertilization can be monitored through plant tissue analysis. Correct interpretation of these results, based on standard levels, is of great importance for correct nutrient management of the crop. However, standard levels are constantly criticized for not considering interactions among elements. To improve the nutritional diagnosis of ‘Paluma’ guava (Psidium guajava L., Myrtaceae), an experiment was conducted using nitrogen fertilization (0, 0.5, 1.0, and 2.0 kg per plant per cycle of N, with urea as a source with 45 % N), and potassium fertilization (0, 0.55, 1.1, and 2.2 kg per plant per cycle of K2O, with potassium chloride as a source with 60 % K2O) in an irrigated commercial area for five consecutive cycles, 2009 through 2012, observing the influence of fertilizers and climate and assessing yield and leaf element content, using the concept of isometric log ratios (ilr) to interpret leaf analysis results (N, P, Ca, Mg, K, and S). This paper showed that nutrient balances and nutrient concentration values can be interpreted coherently using compositional data analysis. Ranges of nutrient balances also were established for “Paluma” guava and validated through ranges grounded in nutrient contents currently used in Brazil. Nitrogen fertilization increased “Paluma” guava yield. The 0.5 kg N application rate per plant and the other studied treatments practically showed the same results, and their values were affected by pruning time as well as the nutrient balances.

RESUMO Apesar de ser amplamente cultivada no Estado de São Paulo, na literatura, há poucas informações sobre os efeitos da adubação e da nutrição em porta-enxertos de caramboleira. O trabalho teve como objetivo avaliar o crescimento das plantas e o acúmulo de Zn em porta-enxertos de caramboleira, submetidos a diferentes doses de zinco. O trabalho foi desenvolvido entre os meses de setembro de 2012 e fevereiro de 2013, em viveiro comercial de produção de mudas, localizado em Taquaritinga-SP. O delineamento foi em blocos casualizados, com cinco doses de zinco: zero; 2,0; 4,0; 6,0 e 8,0 mg dm-3 de Zn, quatro repetições e três plantas por parcela. Os porta-enxertos empregados no experimento estavam com um ano e dois meses de idade e foram cultivados em sacos de polietileno, com casca de pínus como substrato. Aos 170 dias após a aplicação do zinco, avaliaram-se: altura das plantas, diâmetro do caule, número de folhas, massa seca da parte aérea, das raízes e total. A concentração de zinco nas raízes e na parte aérea foi determinada e, em seguida, calculou-se o acúmulo de Zn nas diferentes partes da planta. O zinco influenciou na altura de plantas, diâmetro caulinar, emissão de folhas, acúmulo de massa seca da parte aérea, raízes e total. O maior desenvolvimento dos porta-enxertos de caramboleira esteve associado à dose entre 3,1 e 3,8 mg dm-3 de Zn. Doses elevadas de zinco prejudicam o crescimento e o acúmulo do micronutriente nos porta-enxertos de caramboleira.

ABSTRACT Even though the star fruit is widely grown throughout the state of Sao Paulo, it is lacking information on nutrition and fertilization effects on rootstocks star fruit in literature. The study aimed to evaluate plant growth and how much Zn accumulates in star fruit rootstocks subjected to different doses of zinc. The study was conducted between the months of September 2012 and February 2013, on a commercial seedling production nursery, located in Taquaritinga, SP. A randomized block experimental design was used consisting of five doses of zinc: zero, 2.0; 4.0; 6.0 and 8.0 mg dm-3 of Zn. There were four repetitions and three plants per plot. The age of the rootstocks used in the experiment were one year and two months old and were grown in polyethylene bags, with pine bark as substrate. At 170 days after administering the zinc, the plant height, stem diameter, number of leaves, the dry weight of the shoot, roots and total dry weight were recorded. The zinc content in the roots and shoots was determined, following a calculation of the accumulation of Zn in different parts of the plant. Zinc influenced the plant height, stem diameter, leaf emergence and accumulation of dry matter of shoots, roots and total. Found that the greatest development of star fruit rootstocks was associated with the dose between 3.1 and 3.8 mg dm-3 of Zn. High doses of zinc impair the growth and accumulation of the micronutrient in star fruit rootstocks.

RESUMOA nutrição dos pomares é fator preponderante à produtividade, sendo necessário conhecer as doses adequadas de fertilizantes e sua influência nos atributos qualitativos dos frutos para industrialização. O trabalho objetivou avaliar os efeitos de diferentes doses de nitrogênio e potássio sobre a produtividade de goiabeiras e sobre os valores de pH, conteúdo de sólidos solúveis (SS) e de acidez titulável (AT ), além da relação polpa/miolo das goiabas. O experimento foi conduzido em Vista Alegre do Alto-SP, em pomar de goiabeiras ‘Paluma’, com sete anos deidade, irrigado, manejado com podas, durante três ciclos consecutivos de produção. O solo do pomar é o Argissolo Vermelho-Amarelo distrófico. O delineamento experimental foi em blocos ao acaso, em esquema fatorial, com quatro doses de nitrogênio (0; 0,5; 1 e 2 kg planta-1 de N) e quatro de potássio (0; 0,55; 1,1 e 2,2 kg planta-1 de K2O), com três repetições. A adubação nitrogenada aumentou a produtividade e o pH dos frutos, sendo explicados por modelos quadráticos de regressão polinomial; diminuiu linearmente a relação polpa/miolo e não influenciou os teores de SS e de AT. Por outro lado, a adubação potássica e a interação N x K não apresentaram efeitos significativos sobre a produtividade, bem como sobre as demais características avaliadas.

ABSTRACTThe nutrition of the orchards is the major factor of productivity, being necessary to know the proper doses of fertilizers and their influence on fruit quality attributes for industrialization. This study evaluated the effects of different doses of nitrogen and potassium on the productivity of guava trees and also on the values of pH, soluble solids (SS), titratable acidity (TA) and pulp/kernel ratio of guavas. The experiment was conducted at Vista Alegre do Alto, SPin an irrigated ‘Paluma’ guava orchard, 7 years old, managed with pruning during three consecutivecycles of production. The soil of the area was dystrophic Ultisol. The experimental design was the randomizedblocks, in factorial, with four nitrogen doses (0, 0.5, 1 and 2 kg of N plant-1) and four of potassium (0, 0.55, 1.1 and 2.2 kg of K2O plant-1), with three replications. Nitrogen fertilization increased productivity and the pH of the fruit, being explained by the quadratic polynomial regression models; reduced linearly the pulp/kernel ratio and do not influenced the SS and TA values. On the other hand, potassium fertilizationand N x K interaction had no significant effects on productivity and the other characteristics evaluated.

A quantificação de unidades amostrais que irão compor a amostra promoverá a otimização da mão de obra, além de diminuir erros inerentes à recomendação e avaliação do estado nutricional. A coleta de folhas de forrageiras para a diagnose do estado nutricional é uma etapa importante para subsidiar a adubação, sendo o tamanho da amostra imprescindível para representar adequadamente a população de plantas a ser manejada. Assim, objetivou-se dimensionar o número de amostras de folhas para a diagnose do estado nutricional de capim-elefante irrigado para corte, bem como o índice de clorofila SPAD (Soil Plant Analysis Development). A avaliação foi realizada em capineira de capim-elefante, var. Cameroon, com irrigação fixa de baixa aspersão, em área localizada em Sobral-CE, em solo Neossolo fluvico. Coletaram-se 40 amostras simples, em zigue-zague, de maneira aleatória, escolhendo-se folhas recém-expandidas. As variáveis mensuradas foram os teores foliares de macro (N, P, K, Ca, Mg e S) e micronutrientes (B, Cu, Fe, Mn e Zn) e o índice indireto de clorofila, com auxílio de um clorofilômetro. Considerando aceitável um erro amostral de 10%, a coleta de amostras simples de 16 e 80 plantas, respectivamente, para macro e micronutrientes em capim-elefante seria adequada. Para a medida indireta da clorofila, 8 amostras são necessárias para obter um erro de 10%.

The determination of the amount of sample units that will compose the sample express the optimization of the workforce, and reduce errors inherent in the report of recommendation and evaluation of nutritional status. The leaf collection for diagnosis of nutritional status is an important step, and the sample size necessary to adequately represent the population to be assessed. Thus, the objective was evaluation to the number simple design of leaf samples for the diagnosis of nutritional status of elephant grass irrigated for cutting and SPAD (Soil Plant Analysis Development) index. The study was conducted in elephant grass, with a low fixed sprinkler irrigation, in an area located in Sobral-CE in alluvial soil. It was collected 40 samples simple, randomly, choosing newly expanded leaves. The variables measured were foliar concentrations of macro (N, P, K, Ca, Mg and S) and micronutrients (B, Cu, Fe, Mn and Zn) and the indirect index of chlorophyll, using a chlorophyll meter. Considering an acceptable error of 10%, the collection of single samples of 16 and 80 plants, respectively, for macronutrients and micronutrients in elephant grass would be appropriate. For the indirect measurement of chlorophyll (SPAD index) 8 plants would be required to obtain a 10% error.

O conhecimento sobre a dinâmica dos nutrientes provenientes da aplicação de resíduos orgânicos faz-se necessário, principalmente visando sua a reciclagem, considerando que a quantidade desses materiais tem aumentado rapidamente com o tempo. Assim, objetivou-se avaliar o estado nutricional e a produção de frutos de um pomar de goiabeiras, em função da aplicação do subproduto da indústria processadora de goiabas. O delineamento empregado foi o de blocos casualizados, com cinco tratamentos e quatro repetições, sendo as doses do subproduto (moído) iguais a zero; 9;18; 27 e 36 t ha-1 (peso do material seco). Foram feitas cinco aplicações do subproduto em 2006, 2007, 2008, 2009 e 2010. Avaliou-se o estado nutricional das goiabeiras, via diagnose foliar (macro e micronutrientes), bem como a produção de frutos por seis safras consecutivas. A aplicação do subproduto da indústria processadora de goiabas promoveu alterações no estado nutricional e na produção de frutos. As doses do subproduto incrementaram os teores foliares de N, Mg e Mn da goiabeira. A produção de goiabas cresceu de forma linear em função das doses do subproduto. Os efeitos da aplicação do subproduto foram verificados primeiramente no solo, posteriormente nos teores foliares e, finalmente, na produção de frutos, ao longo das safras.

The knowledge about the dynamics of nutrients from the application of organic waste is needed, especially in order to recycle, since the quantity of these materials has increased rapidly over time. Thus, this study aimed to assess the nutritional status and yield of guava, depending on application of by-product from the guava processing industry. The experimental was a randomized block design with five treatments and four replications, the doses of by-product were equal zero, 9, 18, 27 and 36 t ha-1 (dry weight of the material). There were five applications of waste in 2006, 2007, 2008, 2009 and 2010. It was evaluated the nutritional status of guava (macronutrients and micronutrients), as well as fruit production for six consecutive years. The application of by-product in guavas processing industry promoted changes in the nutritional status and fruit production. Doses of by-product increased foliar content of N, Mg and Mn. Fruit yield increased linearly as a function of residue doses. The effects of the by-product were observed primarily in the soil, then in the leaf contents and finally in the production of fruits along the seasons.

A utilização de fontes alternativas de nutrientes, provenientes especialmente de resíduos e subprodutos da agroindústria, pode ser estratégia importante na ciclagem de elementos essenciais, garantindo destino adequado de materiais que seriam descartados. Assim, objetivou-se avaliar a aplicação de doses do subproduto da indústria processadora de goiabas sobre a fertilidade de um Argissolo, sob pomar de goiabeiras. As doses de resíduo foram estabelecidas em função dos teores de N no material. O delineamento empregado foi o de blocos casualizados, com cinco tratamentos e quatro repetições, sendo as doses do resíduo (moído) iguais a: zero; 9; 18; 27 e 36 t ha-1 (peso do material seco). Foram feitas cinco aplicações do subproduto em: 2006, 2007, 2008, 2009 e 2010. O subproduto da indústria processadora de goiabas promoveu alterações na fertilidade do solo do pomar. Com o aumento das doses, houve incremento das concentrações de fósforo no solo em todas as análises realizadas. As concentrações de manganês aumentaram, e houve redução do valor pH do solo nos últimos anos de condução do experimento. Observou-se, na camada subsuperfical (0,20-0,40 m), após a aplicação contínua do subproduto, aumento na concentração de fósforo em função das doses do subproduto.

The use of alternative sources of nutrients coming especially from waste and industrial by-products can be an important strategy in nutrient cycling, ensuring proper destination of materials that would otherwise be discarded. The objective was to evaluate the application of doses of by-product of guava processing industry on fertility of an Ultisol in a guava orchard. Doses of waste were established on the basis of N content in the material. The experimental design was a randomized block design with five treatments and four replications, the doses of the residue equal to zero, 9, 18, 27 and 36 t ha-1 (dry weight of the material). There were five applications residue: in 2006, 2007, 2008, 2009 and 2010. The by-product of the guava processing industry promoted changes in soil fertility in the orchard. With increasing doses increased the concentrations of phosphorus in the soil in all analyzes. The manganese concentrations increased and decreased the soil pH value in the last years of the experiment. It was observed in the subsuperfical layer (0.20-0.40 m) after continuous application of by-product an increase in phosphorus concentration as a function of the doses of the by-product.

Informações sobre a mineralização de subprodutos são importantes para o correto manejo desses materiais em áreas agrícolas. Assim, objetivou-se avaliar a mineralização do nitrogênio proveniente do resíduo da indústria processadora de goiabas, aplicado em Argissolo cultivado com goiabeiras. Amostras do solo mais o subproduto foram acondicionados em frascos de polietileno com capacidade de 0,25 dm³. Foram pesados 100 g de solo mais o resíduo referente a cada tratamento (doses do subproduto: 0; 9; 18 e 36 t ha-1), sendo tal procedimento realizado em triplicata. O período máximo de incubação foi de 11 semanas, analisando-se as amostras nos seguintes tempos: 0; 7; 14; 28; 42; 56; 70; 84; 98; 112 e 126 dias. A umidade foi corrigida para 70% da capacidade de retenção de água do solo, sendo monitorada diariamente através de pesagens dos potes. Nos tempos estabelecidos realizou-se a desmontagem de três frascos correspondentes a cada tratamento, determinando-se o nitrogênio inorgânico. Pode-se afirmar que a mineralização do N ou a liberação é lenta, ou seja, não há rápida disponibilização de nitrogênio. No período avaliado, 126 dias, a fração média de mineralização foi de 23% e, a meia vida média de 73 dias.

Information on the mineralization of residues are important for proper management of these materials in agricultural areas. The objective was to evaluate the mineralization of nitrogen from the residue of guava processing industry, applied in a Ultisol cultivated with guava trees. Soil samples and the residue were placed in polyethylene pots with a capacity of 0.25 dm³. Around 100 g of soil plus waste were weighed in each treatment (doses of residue: 0, 9, 18 and 36 t ha-1), with such a procedure being performed in triplicate. The maximum incubation period was 11 weeks, with analyses at 0, 7, 14, 28, 42, 56, 70, 84, 98, 112 and 126 days of treatment. The soil+residue humidity was adjusted to 70% of the soil water retention capacity and monitored daily by weighing the pots. The inorganic nitrogen was measured in each evaluation time. It can be stated that the N mineralization or release is slow and there is not rapid availability of nitrogen. Over the period of 126 days, the mean fraction of mineralization was 23% with the half-life of 73 days.