The boron (B) fertilization in soybean is important to ensure great yields. Boron correction must be applied in deficient soils repairing losses, exports and leaching. The objective of this study was to evaluate the effects of doses, methods and times of application of B in soybean B content and yield. The field experiments were conducted during the 2015/16 and 2016/17 cropping seasons and set as a randomized block design with nine treatments (0, 0.5, 1, 1.5, 2 kg ha-1 of B, 0.5 kg ha-1 of B mixed with NPK (02-28-18) in furrow during sowing, foliar application with 0.3 kg ha-1 of B in V4 soybean stage, foliar application with 0.3 kg ha-1 of B in R1 soybean stage, and foliar application of 0.15 kg ha-1 in V4 plus 0.15 kg ha-1 of B in R1 soybean stage) and four replications. Boric acid was the B source and the variables analyzed were: B leaf content, B exported in seeds, number of pods per plant, number of seeds per pod, weight of 100 seeds (g) and productivity (kg ha-1). The levels of B in leaf were between 30.1 and 43.8 mg kg-1 and between 65.0 and 92.6 mg kg-1 in the 2015/16 and 2016/17 growing season, respectively. Exports of B in seeds were estimated between 166 and 248 g ha-1 and between 208.9 to 260.8 g ha-1 in the 2015/16 and 2016/17 growing season, respectively. Great productivity (3,820 kg ha-1) was observed in the 2016/17 growing season, with an estimated dose of 0.95 kg ha-1 of B.

A adubação com boro geralmente é aplicada sem orientação adequada, usando sempre a filosofia de segurança, podendo acarretar problemas de nutrição nas plantas. O objetivo do trabalho foi avaliar os efeitos da aplicação de boro e capacidade de retenção de água no solo, nos componentes de produção, na produtividade e no acúmulo de boro na soja. Realizou-se um experimento em Ipameri-Go no ano agrícola de 2015/2016. O delineamento foi inteiramente casualizados (DIC) no esquema fatorial 3 x 5, sendo o primeiro fator disponibilidade de água (50; 70 e 90% da capacidade máxima de retenção de água no solo - CRA), e o segundo as doses de boro (0; 0,5; 1,0; 1,5 e 2,0 mg dm-3), com 4 repetições, em vasos de 5 dm3 de solo. Foram analisados o número de vagens/planta, número de grãos/vagem, massa seca da parte aérea e raiz, acúmulo de boro na parte aérea, raiz e acúmulo total de boro, a massa seca de 100 grãos e a produtividade por planta. Os resultados foram submetidos à análise de variância e de regressão. Verificou-se interação entre doses de boro e CRA. Com a CRA de 50% as plantas não respondem a adubação boratada. Com a disponibilidade de água de70% da CRA, o acúmulo de boro é crescente com as doses, mas a massa seca de raiz e de parte aérea, o número de vagens por planta e a produtividade de grãos aumentam até as doses de 0,7 a 1,0 mg dm-3. Quando a disponibilidade de água no solo é alta (CRA 90%), a massa seca de parte aérea e raiz, o acúmulo de boro na planta e número de vagens por planta aumentam até a dose máxima testada, de 2,0 mg dm-3. Palavras-chave – Glycine max L., disponibilidade de água, micronutriente, adubação

Resumo: O nitrogênio é um dos nutrientes mais exigidos pelas plantas. Também é normalmente encontrado em grandes quantidades nos adubos orgânicos. Se absorvido em excesso, pode se acumular no vacúolo das células das plantas como nitrato, e levar à metamioglobina tóxica e à formação de nitrosaminas. Este trabalho objetivou-se avaliar a adubação com cama de frango e esterco bovino de curral na produtividade, teores de N total e nítrico na parte aérea da cultura da rúcula. O delineamento experimental foi em blocos casualizados, em esquema fatorial 2x5, com quatro repetições. Foram testados dois adubos orgânicos (cama de frango e esterco bovino), e cinco doses (0, 10, 20, 30 e 40 t ha -1 ). O experimento foi implantado em condições de campo, em um Latossolo Vermelho-Amarelo Distrófico. A parcela experimental foi constituída por quatro linhas, espaçadas de 0,25 m, e com 1 m de comprimento. Aos 40 dias após o transplante das mudas, foram avaliados a altura de plantas (usando-se uma régua, a partir do nível do solo até a extremidade das folhas mais altas), número de folhas por planta (folhas maiores que cinco centímetros de comprimento, partindo-se das folhas basais até a última folha aberta). A maior massa fresca de plantas foi obtida com 24,14 t ha -1 de esterco bovino, enquanto que com cama de frango a produtividade aumentou até 40 t ha -1 . Os teores de N-NO 3 -aumentaram linearmente com as doses de esterco bovino de curral, mas não ultrapassaram os limites toleráveis com ambas as fontes. Palavras-chave: Eruca sativa Mill; resíduos orgânicos; nitrogênio.Abstract: Plants needs high amount of nitrogen. It is also an abundant element in organic fertilizers. If absorbed in excess can accumulate in the vacuole of the cells of the plants as nitrate. Excessive intake of nitrate for human or animal can result in the formation of toxic metmyoglobin and nitrosamines. This study aimed to evaluate the fertilization with poultry litter and cattle manure on productivity, and total nitric N content in rocket culture. The experimental design was randomized blocks in a 2x5 factorial, with four replications. The treatments consisted of a combination of two organic fertilizers (cattle mannure and poltry litter) and five doses (0, 10, 20, 30 and 40 t ha -1 ). The experiment was carried out in field conditions, in a Oxisol dystrophic. The experimental plot consisted of four rows, spaced 0.25 m, and 1 m in length. 40 days after transplanting the seedlings were evaluated the plant height, number of leaves per plant, total N uptake and nitrate (N-NO3) in the rocket leaves. The highest value of fresh matter plants was obtained with 24.14 t ha -1 of manure, whereas with poultry litter productivity increased up to 40 t ha-1. The N-NO3 content increased linearly with cattle manure doses, but did not exceed the tolerable limits with both sources.

This study aimed to evaluate six cauliflower genotypes regarding their resistance to black rot and their production performance. To do so, it was conducted two field experiments in Ipameri, Goiás, Brazil, in 2012 and 2013. It was used a randomized block design, with four replications (total of 24 plots). Each plot consisted of three planting lines 2.5 m long (six plants/line), spaced 1.0 m apart, for a total area of 7.5 m2. Evaluations of black rot severity were performed at 45 days after transplanting, this is, 75 days after sowing (DAS), and yield evaluations at 90 to 105 DAS. The Verona 184 genotype was the most resistant to black rot, showing 1.87 and 2.25% of leaf area covered by black rot symptom (LACBRS) in 2012 and 2013. However, it was not among the most productive materials. The yield of the genotypes varied between 15.14 and 25.83 t/ha in both years, Lisvera F1 (21.78 and 24.60 t/ha) and Cindy (19.95 and 23.56 t/ha) being the most productive. However, Lisvera F1 showed 6.37 and 9.37% of LACBRS and Cindy showed 14.25 and 14.87% of LACBRS in 2012 and 2013, being both considered as tolerant to black rot.

Oxidação de enxofre elementar em diferentes fontes e doses de fertilizantes Elementary sulfur oxidation in different sources and doses of fertilizers

Potato is a plant that has high nutrient demand during its cycle. Given the concern with the environment, due to the large amount of synthetic mineral fertilizer used in the crops, the objective of this work was to evaluate the efficiency of organomineral fertilizers in the cultivation of potato, cultivar Ágata, under cerrado conditions. The experimental design was in subdivided plots, consisted of four doses of organomineral fertilizer, corresponding to 40, 60, 80, 100 and 120% of the mineral fertilizer dose in the organomineral source (2800 kg ha-1 of formulated 3-32-6) and the subplots consisted of four collection seasons (61, 74, 89 and 110 days after planting) and four repetitions. Organomineral fertilizer with 40% of the recommended dose for potato cultivation provides higher yield of tubers in the Especial potato class and higher accumulation of total dry mass, in addition to providing satisfactory productivity for the tubers of higher commercial value. The use of organomineral fertilizers promotes the same behavior as mineral fertilizers, not interfering with potato development.

Corn has great relevance for agribusiness as it is used in human and animal food, besides the energy matrix. The objective of this study was to assess the leaf content of macro and micronutrient, accumulation of primary macronutrients, production components and productivity with the application of pelleted organomineral fertilizer in different doses compared to mineral fertilization, in two soils of different textures in the corn crop. Two trials were conducted in the municipality of Uberlândia-MG-Brazil: one located near the highway BR 452 km 141, at the coordinate 18°55′26″S, 48°09′36″W, clay soil. The other at km 640 of BR 365, at coordinate 18°54′05″S, 48°25′20″W, sandy soil. A randomized block design with five replications was used, with five doses of organomineral fertilizer (40, 60, 80, 100 and 120% of the recommended dose of P2O5 for corn) and an additional with 100% of the recommendation of mineral P2O5, total of six treatments and 30 plots. The results showed that, with the exception of phosphorus leaf content, yield in the sandy texture and the number of grains per row in the clay texture, there was no difference between the doses of phosphate organomineral and did not differ from the mineral. Thus, phosphate organomineral is as efficient as mineral for phosphorus supply.