Resumen

FLEITAS CENTURION¹, Adriana  y  GRABOWSKI OCAMPOS*1, Cristhian J.. Biological control of the fungi complex that cause leaf spot on sweet corn (Zea mays var. saccharata) with beneficial bacteria. Investig. Agrar. [online]. 2014, vol.16, n.2, pp.83-92. ISSN 2305-0683.

In order to evaluate the efficiency of Bacillus sp., Pseudomonas fluorescens, and Streptomyces sp. in the control of leaf spot of sweet corn and determine the mechanism of action exerted by them, experiments were carried out at the Phytopathology Laboratory and in the experimental field of the Facultad de Ciencias Agrarias, San Lorenzo. Experiment 1 consisted in determining in vitro the inhibition of the growth and development of the complex of pathogens associated with this etiology through the production of anti microbial water soluble compounds and non-specific volatile gases produced by bacteria. It was registered the percentage reduction of mycelial growth and percentage inhibition of the germination of conidia. The experiment 2 consisted in determining under field conditions the reduction of the intensity of the disease in sweet corn plants. The treatments were each bacteria suspension, an absolute control and a chemical control (Azoxystrobin 20% + Tebuconazole 20%). In vitro, the mycelial growth of Bipolaris sp., Curvularia sp. and Exserohilum turcicum reduced significantly and the germination of E. turcicum was inhibited by the three bacteria. In the field experiment, it was confirmed the significant control efficiency of the three studied bacteria. Bacillus sp. reduced the intensity by 43%, Pseudomonas fluorescens by 36% and Streptomyces sp. by 19%. The three beneficial bacteria are agents of biological control for producing antagonistic effect and reducing the severity of leaf spot in sweet corn.

Palabras clave : Zea mays; beneficial bacterias; biological control; fungi complex.

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