Desempenho agronômico a campo de híbridos de milho inoculados com Azospirillum

O uso de inoculantes na cultura do milho tem sido cada vez mais valorizado, em vista dos beneficios que pode trazer a cultura, como a fixacao biologica do nitrogenio e o aumento da quantidade de raizes. Isto pode melhorar a absorcao de agua e nutrientes pela planta, contribuindo para o desenvolvimento do milho, principalmente em periodos de seca. Este estudo foi desenvolvido com o objetivo de avaliar, em condicoes de campo, as caracteristicas agronomicas e o rendimento de graos de hibridos de milho, inoculados, ou nao, com uma mistura de tres especies de Azospirillum (A. brasilense, A. lipoferum, A. oryzae). Foram avaliados o teor relativo de clorofila nas folhas, a altura de planta, a senescencia foliar, os componentes de rendimento de graos, o teor de N, a materia seca da parte aerea das plantas e o numero mais provavel de bacterias diazotroficas na rizosfera das plantas. A inoculacao manteve o teor de clorofila significativamente maior ate o estadio R3 das plantas, para os tres hibridos testados, aumentou o rendimento da materia seca da parte aerea, dos hibridos AS 1575 e SHS 5050, o peso de 1000 graos, para o hibrido P32R48 e altura, para o AS 1575. Houve interacao entre os genotipos de milho e as bacterias inoculadas, visto que, cada hibrido testado respondeu de forma diferente a inoculacao. A inoculacao de Azospirillum em milho demonstrou estimular o desenvolvimento das plantas no periodo vegetativo, aumentando a probabilidade de obter-se um estande de plantas uniforme, maior resistencia ao estresse e maior concentracao de clorofila nas folhas.

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