Abstract

VITAL-LOPEZ, L; CRUZ-HERNANDEZ, MA; FERNANDEZ-DAVILA, S  and  MENDOZA-HERRERA, A. Bacterial diversity in the rhizosphere of a transgenic versus a conventional maize (Zea mays). Phyton (B. Aires) [online]. 2016, vol.85, n.2, pp.210-217. ISSN 1851-5657.

Genetically modified crops could cause negative effects on bacterial communities. In this study, we compared the bacterial community structure of two maize cultivars to determine whether the transgenic cultivar exerts a negative effect on bacterial communities inhabiting the rhizosphere. Cultivars included the genetically modified maize (Zea mays), with the pat-gene conferring resistance to the herbicide glufosinate (synonym: L-phosphinothricin), and the hybrid, conventional maize. Metagenomic DNA was extracted from the rhizosphere of plants grown in a greenhouse. Single-strand conformation polymorphism, based on polymerase chain reaction amplifying a partial subunit rRNA gene was used to characterize and generate genetic profiles that corresponded to the bacterial communities of the amplified products from the rhizosphere of the two maize cultivars. Genetic profiles of the rhizospheres consisted of distinguishable profiles, based on the chosen primer pairs. Similarity analyses of patterns found by binary matrix analyses showed no differences in the bacterial communities of the two cultivars. This analysis showed that the microbial population’s structures of the conventional and genetically modified maize were very homogeneous. Genetic modification did not adversely afect the structural bacterial community in the rhizosphere of the transgenic maize cultivar.

Keywords : Zea mays; Glufosinate; Metagenomic DNA; Rhizosphere; Single-strand conformation polymorphism.