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Brazilian soils are typically highly weathered, naturally poor in P, and rich in minerals with high P-adsorbing capacity. The objective of th e present study was to evaluate the efficiency of peat-based granulated organomineral phosphate fertilizer (OMF) on the phosphorus supply capacity, shoot dry matter production and P accumulation of corn plants, as well as its residual effect on soil, compared to that of monoammonium phosphate (MAP). The experimental was performed using a randomized block design with a 2 × 5 + 1 factorial scheme (two fertilizer: OMF and MAP; five P doses: 15, 30, 45, 60, and 75 mg P2O 5 dm-3 , and one control treatments (no P fertilizer), and three replicates. Two soils (Ferralsol and Planosol) were used in this study. Soil samples were incubated with limestone for 30 days and then dried, sieved and used to fill plastic pots (3 dm3 soil per pot). Four successive corn cultivations were evaluated and, at the end of each cultivation period, the shoot dry mass (SDM) and P content of the corn were determined. In addition, soil P was measured at the end of the experiment. OMF and MAP had similar effects on SDM, but MAP provided higher P accumulation (SPA) of the first two cultivations, while OMF had higher soil residual P in Ferralsol. However, considering the total accumulated in four crops, SDM and SPA were statistically similar between the two P sources. SDM and SPA in Ferralsol increased linearly with increasing doses, while in Planosol, SPA increased linearly with increasing P dose, regardless of the P source, but SDM was not affected by increasing P doses. According to the results, OMF composed of chemically activated peat and MAP can replace MAP as phosphate fertilizer and maintain the same agronomic efficiency. Made available in DSpace on 2022-08-08T11:19:22Z (GMT). No. of bitstreams: 1 Effect-of-phosphate-organomineral-fertilization-2022.pdf: 1042926 bytes, checksum: 4294c92a53ab45a064969488985c238d (MD5) Previous issue date: 2022

Objetivou-se avaliar a eficiência de um fertilizante organomineral (FOM) granulado a partir da mistura de turfa e cloreto de potássio na produção de gramíneas, em comparação ao cloreto de potássio comercial. O experimento foi conduzido em vasos em casa de vegetação. A planta indicadora foi o milho (Zea mays cv. Ipanema) durante os três cultivos iniciais e braquiária (Brachiaria brizantha cv Marandu) no quarto cultivo. O delineamento experimental foi em blocos casualizados em esquema fatorial 2 x 2 x 6, com três repetições, sendo duas classes de solo (Latossolo Vermelho Amarelo (LVA) e Planossolo Háplico (SX)) duas fontes de K2O (KCl comercial e FOM) e seis doses de K2O (0, 15, 30, 45, 60 e 75 mg dm-3). Em todos os cultivos, a parte aérea das plantas foi coletada para obtenção da massa seca e do conteúdo de K no tecido. Nas condições estudadas, os fertilizantes proporcionaram resultados semelhantes em todos os cultivos analisados e no acumulado dos cultivos para a massa seca da parte aérea. As maiores diferenças no acúmulo de K e na produção de massa seca da parte aéreas foram proporcionadas pela aplicação das maiores doses de K2O, independente da fonte. As maiores doses de K2O em SX proporcionaram maior eficiência relativa de FOM, indicando o maior potencial da aplicação deste fertilizante em solos de textura arenosa. De modo geral, os resultados obtidos demonstram o potencial do desenvolvimento e aplicação de fertilizantes organominerais. Made available in DSpace on 2020-08-07T11:11:55Z (GMT). No. of bitstreams: 1 Acumulo-de-biomassa-e-potassio-em-gramineas-em-funcao-da-fonte-fertilizante-e-do-solo-2020.pdf: 1084603 bytes, checksum: 3047ec58adcfa5a99506a81ccfb5ef4b (MD5) Previous issue date: 2020

The objective of this work was to evaluate the efficiency of granulated fertilizers based on potassium chloride with humic acids in the production of dry matter and the accumulation of macronutrients in corn plants. The experiment was carried out in a greenhouse, using soil samples from the 0-20 cm depth layer of a Planossoloháplico. A completely randomized block design was adopted, in a 2 x 5 + 1 factorial scheme with two sources of humic acid extraction (vermicompost and peat), five concentrations of humic acids in the granulations (0; 2.5; 5.0; 7.5 and 10.0%) and one additional treatment that consisted of the application of commercial potassium chloride, with three replications. The plants were collected at sixty days after sowing. There was a slight difference in the production of the dry root mass. The P accumulation presented the most pronounced differences, whereas the granulated potassium chloride with humic acid extracted from vermicompost showed the best performance. Made available in DSpace on 2020-08-06T11:12:10Z (GMT). No. of bitstreams: 1 Performance-test-of-granulated-potassium-chloride-with-humic-acids-addition-2020.pdf: 724342 bytes, checksum: 0de59bf2ba9b94334c94544be40586f1 (MD5) Previous issue date: 2020