Abstract

CASTILLO-ORTEGA, LS; MERCADO-FLORES, Y; TELLEZ-JURADO, A  and  ANDUCHO-REYES, MA. Identification of rhizobacteria isolated from Tagetes coronopifolia and Tagetes terniflora (Marigold) and evaluation of their in vitro inhibitory capacity against phytopathogenic microorganisms. Biotecnia [online]. 2022, vol.24, n.3, pp.150-158.  Epub June 19, 2023. ISSN 1665-1456.  https://doi.org/10.18633/biotecnia.v24i3.1736.

The genus Tagetes represents a group of plants commonly known as marigold or “flower of the dead”, which are mainly recognized for their use in the food industry, ornamental horticulture, therapeutic herbalism, and culture. Tagetes coronopifolia and terniflora are two plant species of this genus, which are used for crop rotation and control of phytopathogenic nematodes. In this work, 581 rhizobacteria strains were isolated from samples of rhizosphere soil, soil attached to the root surface and inside of plant root at 30, 60, 90 and 120 days of growth in greenhouse cultures. Twenty-two strains showed antagonistic activity against Fusarium sp. and 53 against Stenocarpella maydis, which are pathogenic fungi in corn, while 37 strains showed antagonism against Clavibacter michiganensis subsp. michiganensis. According to the percentage of inhibition of the phytopathogens, 10 rhizobacteria were selected for molecular identification of the partial 16S rDNA gene. The partial sequences of each rhizobacteria were analyzed for similarity in the GenBank, showing as a result that they belong to the Bacillus and Pseudomonas genera, which are used as biocontrol agents.

Keywords : rhizobacteria; endophytic bacteria; biological control; antagonistic plants.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )