Desempenho de híbridos de milho em função da aplicação de fungicidas foliares

Abstract

Maize production has great social and economic importance in Brazil, what is pointed out for the growth of cultivated area and for the increase in production throughout the years. However, its productivity can be decreased by leaf diseases, caused by many pathogens. Disease control must integrate different strategies, with emphasis in resistant or tolerant maize hybrids, likewise the use of fungicides, that can be of great use for keeping the productive potential of the plants. All things considered, the objective of this work was to analyze the performance of three commercial hybrids of maize, also using fungicides in order to control leaf diseases in second crop maize. The experiment was installed in Uberlândia - MG, during the second harvest of the 2020/2021 agricultural year. The experimental design was randomized blocks, with five treatments, composed by a control treatment and the others with different combinations of fungicides. The genotypes that were used were the hybrids named NK508, NK520 VIP3 e NK511 VIP3. The characteristics evaluated were leaf disease severity, green leaf area, plant height, ear insertion height, final plant population and productivity. In the conditions of the present work, the hybrid NK508 showed itself as the less susceptible to the leaf diseases between the studied hybrids, but still presented responsivity to chemical control. The hybrid NK520 VIP3 showed itself as more sensible to the leaf diseases, what lead to great productivity amplitude between the treatments. Hybrid NK511 VIP3 showed itself also susceptible to the leaf diseases, but with great productive potential, which was emphasized by the productivity results between treatments. Between the fungicide treatments, T5 (T+E V¬8 / C+T VT-R2) had emphasis, because it presented low leaf disease severity values, also high green leaf area and productivity values.