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The objective of this study was to develop and validate a diagrammatic scale to evaluate the severity of spots on maize leaves caused by the fungus Diplodia macrospora. Severity ranged between the minimal (0.5%) and maximal (55%) limits of disease severity, and intermediate severity levels were defined according to the "Weber-Fechner stimulus response law". The proposed scale describes six levels of severity based on how much of the leaf is affected: 0.5%, 3%, 8%, 23%, 36%, and 55%. Validation was carried out by eight evaluators, four inexperienced and four experienced. They estimated the severity of disease in 60 maize leaves, with and without the proposed diagrammatic scale. A relationship was shown by regression analysis between estimated and actual severity, with and without the use of the scale. When both inexperienced and experienced evaluators used the scale, they were able to estimate disease severity more accurately and precisely.

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Common bean (Phaseolus vulgaris L.) is one of the main Brazilian agricultural crops. Numerous diseases have affected such a crop during its life cycle, such as white mold, caused by Sclerotinia sclerotiorum. This fungus is quite aggressive and requires an intensive use of pesticides. This study aimed at evaluating white mold control and antimicrobial activity against S. sclerotiorum using extremely diluted aqueous solutions of Phosphorus and Calcarea carbonica, at 6CH, 12CH, 24CH, 36CH and 48CH dynamizations (centesimal Hahnemannian). The tests were carried out in a completely randomized design, with 10 treatments and 5 replicates each, considering water as control. Variables including disease progression, the number of dead plants, the number of sclerotia, and mycelial growth were evaluated by in vivo and in vitro tests. The treatments Phosphorus 12CH, Phosphorus 48CH, Calcarea carbonica 12CH, and Calcarea carbonica 48CH presented resistance-inducing action by slowing down the disease progression up to 83% and decreasing the number of dead plants up to 90%. In vitro tests showed that the treatments Phosphorus 12CH, Phosphorus 48CH and Calcarea carbonica 48CH slowed down the mycelial growth. The latter also completely inhibited the production of sclerotia. These results indicate the potential of Phosphorus 12CH, Phosphorus 48CH, Calcarea carbonica 12CH, and Calcarea carbonica 48CH for controlling S. sclerotiorum in common beans.

The frequent use of the similar formulated fertilizers has reduced the supply of micronutrients to the crops. The application of micronutrients through leaf has increased the crops productivity. In this context, this study aimed to assess the effects of copper and zinc micronutrient applications in biometric variables and grain yield of maize crop. The experiment was conducted at the Agricultural Research Center of Copacol, using copper phosphite and zinc phosphite, using treatment (1) 100 g.ha -1 of copper, treatment (2) 500 g.ha -1 of zinc, treatment (3) 100 g.ha -1 of copper + 500 g.ha -1 of zinc and the treatment (4) witness (control). The treatments were applied at V6 phenological stage of maize with costal pump. The experimental design was randomized blocks with six repetitions. The variables measured were: number of plants per plot, number of spikes per plot, number of rows per spikes, number of grains per row and number of grains per spike, thousand grains weight and productivity of grains. For thousand-grain weight, there was higher effect of micronutrient treatments, compared to the control. For number of grains per row, there was no significant effect. However, application of single Zn showed better effects than Zn+Cu. In conclusion, application of Zn via leaf increased productivity. The Zn increased productivity of maize even when used in the soil with high Zn content.

The adoption of different fertilizer application methods should consider the operational, agronomic and economic aspects. The objective of this work was to study the fertilization response with potassium in the soybean crop at different times of application and different potassium sources in an Eutroferric Red Latosol. The experiment was carried out in the municipality of Formosa do Oeste-PR. The design was in a randomized block in a factorial scheme (2 × 5) +1, with 2 potassium sources: normal KCl (KCl) and polymer-coated KCl (KCl-polymer), the KCl doses were adjusted to 40 kg ha -1 of K2O, the second factor refers to the splitting of K2O dose in five application times: T1, application of K2O was nine days before sowing, T2 application split up being ½ of the dose nine days before sowing + ½ of the dose of K2O at sowing, T3 application of the total dose of K2O at sowing, T4 ½ of the dose at sowing + ½ at the V3 phenological stage of the crop, T5 application of K2O was total at the V3 stage of the crop. And an additional witness, without K2O application. KCl-polymer was more efficient for application to the haul before sowing the crop. The fertilization with KCl was better when applied at the V3 stage of the crop. Fertilization with KCl-polymer resulted in higher K content in the leaf, higher efficiency of fertilizer use reflecting in higher productivity.

This review article has aimed at environment and impact of different pollutants, define, classify, analyze and cite methods of remediation according to Brazilian environmental legislation. Concerns about the preservation of the environment is extensively debated nowadays, with a view mainly to the production of effluents in agriculture, toxic metals, emerging pollutants and excessive use of agrochemicals. However, some impacts are necessary to meet the needs of economic development and social to ensure they are carried out rationally. Furthermore, application of remediation methods reduce the impact of these pollutants as small as possible. In this sense, the environment's definition, the main current impacts, the size and consequences of these and some remediation methods, as well as Brazilian environmental legislation will be addressed.

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