Banca de DEFESA: KENNEDY XAVIER DA SILVA JÚNIOR

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : KENNEDY XAVIER DA SILVA JÚNIOR
DATE: 01/08/2023
TIME: 09:00
LOCAL: VIDEOCONFERÊNCIA
TITLE:

Strategy for the use of enhanced efficiency nitrogen fertilizers in the sustainable production of corn for silage. 

KEY WORDS:

Enhanced efficiency fertilizers, nitrogen management, volatilization.

PAGES: 87
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SUMMARY:

High losses due to nitrogen volatilization in ammoniacal nitrogen fertilizers, mainly urea, when applied on the soil surface in addition to the decrease in labor supply, have led farmers to seek new strategies to reduce field operation and increase nutrient use efficiency. This work aimed to assess the effectiveness of a single nitrogen application at planting, using enhanced efficiency fertilizers and urea at different doses of nitrogen (40, 80, 120 and 160 kg of N ha-1), to know whether this application strategy would be sufficient to meet the nitrogen demand by the plant throughout its cycle. In parallel, split application was carried out, for comparison purposes, with 30% of the nutrient dose at planting and the remainder at side dressing at the V6 phenological stage of the corn plant. The experiment was carried out at the Agricultural Research Corporation of the State of Rio de Janeiro – PESAGRO, in Seropédica (RJ). The experimental design consisted of randomized blocks in a 2x4x2 factorial scheme (2 fertilizer sources, 4 nitrogen doses and 2 application modes), with four replications. Parameters such as green mass productivity, plant height, stem diameter and ear weight were measured. The chlorophyll content was also determined at the V3, V7, V11, and VT development stages, using a chlorophyll meter, as well as the nitrogen content at the same stages through the sulfuric digestion method. The data set was analyzed using R statistical software, the means compared by Tukey's test at a 5% probability level and regression analysis was used for the doses. The results revealed that the strategies used for nitrogen supply, as well as the different doses and sources tested, did not affect the silage green mass productivity, plant height and ear weight. The enhanced efficiency fertilizer applied at side dressing at the dose of 80 kg of N ha-1 produced plants with larger stem diameters, reflecting directly on the silage green mass productivity. This suggests that the relationship between productivity and nitrogen doses is not strictly linear. Both sources of fertilizers adequately supplied nitrogen to the plants at different doses and management strategies. On the other hand, the dose of 40 kg of N ha-1 applied at planting did not supply enough nitrogen, which impaired the implementation of this strategy and dose under the conditions the experiment was conducted.

COMMITTEE MEMBERS:
Externo à Instituição - ADRIANO PORTZ - UFF
Presidente - 2213075 - EVERALDO ZONTA
Interno - 2626406 - LEANDRO AZEVEDO SANTOS