Fenotipic and molecular identification of Burkholderia spp in rice panicles (Oryza sativa L.)

Abstract

The disease known as bacterial blight of rice is caused by Burkholderia glumae, Burkholderia gladiolii and the blight of rice seedlings caused by Burkholderia plantarii, are bacteria considered important in rice cultivation (Oryza sativa L.). The effects have increased in recent years causing large annual economic losses in the countries that produce this grain. The objective of this research was to identify, through phenotypic and molecular tests, Burkholderia species in rice panicles (Oryza sativa L.). The collection of samples was carried out in the municipality of Sébaco, Matagalpa in the TAI-NIC Experimental Center and farm Virginia, Agricola Miramontes in the department of Boaco and farm La Doña, municipality of Malacatoya, Granada. Bacteria were isolated from panicles with symptoms of the disease and species identification was performed by biochemical tests (carbohydrates and differentiation). Confirmation of the Burkholderia species was carried out using the molecular technique PCR (Polymerase Chain Reaction). The isolates of B. gladiolii in the King B medium presented grayish white or yellowish colonies, producing the non-fluorescent diffuse yellow pigment, while B. plantarii showed yellow, translucent, and convex, non-fluorescent colonies, in the case of B. cepacia colonies were translucent, convex, non-fluorescent. Identification with biochemical tests showed the presence of 18 positive isolates for B. gladiolii, two isolates for B. plantarii and one positive for B. cepacia. With the PCR technique, 18 positive samples were identified for B. gladiolii that amplified 479 bp fragments and two positive samples for B. plantarii with 597 bp fragments. In the case of B. glumae, it was not identified by phenotypic or molecular tests.