Article

Microorganismos benéficos como biofertilizantes eficientes para el cultivo del tomate (Lycopersicon esculentum, Mill)

Revista Colombiana de Biotecnología 01/2005;
Source: DOAJ

ABSTRACT En el uso y manejo de biofertilizantes en la agricultura, uno de los principales problemas es el desconocimiento de las especies presentes en los agroecosistemas y en la rizosfera de los cultivos, para su posible utilización eficiente. Desde el punto de vista ecológico, es importante conocer los integrantes de la comunidad bacteriana que favorecen su aplicación como inoculantes y propician un efecto agrobiológico positivo en los cultivos agrícolas. Esta investigación se desarrolló con el objetivo de evaluar la efectividad agrobiológica de Azospirillum sp, en el crecimiento, desarrollo y rendimiento en el cultivo del tomate. Para ello, se partió de seleccionar el género microbiano predominante en la rizosfera del cultivo y posteriormente se evaluó el efecto de su inoculación a partir de la respuesta del cultivo. Los resultados demostraron que los géneros Pseudomonas, Azospirillum, Azotobacter, Bacillus y Streptomyces, forman parte de la comunidad microbiana de la rizosfera del tomate, en las condiciones estudiadas, y que Azospirillum es el género dominante. La inoculación artificial de esta rizobacteria causó un efecto positivo sobre el crecimiento de las plántulas, así como en el estado nutricional de las plantas, con un rendimiento agrícola superior a un 11 % con respecto a las plantas testigo. Se obtuvo un alto nivel poblacional en la rizosfera de las plantas inoculadas.Palabras clave: rizosfera, inoculante, crecimiento, rendimiento.One of the main problems regarding the efficient use and management of biofertilizers in agriculture lies in the unknown species present in agro-ecosystems and crop rhizospheres. From the ecological point of view, it is important to know the members of the bacterial population allowing them to be applied as inoculants and enable a positive agro-biological effect on agricultural crops. This investigation was aimed at evaluating the agro-biological effectiveness of Azospirillum sp. on tomato growth, development and yield. The predominating microbial genus in the crop rhizosphere was thus selected and the effect of inoculating it was then evaluated, judging by the crop's response. Results showed that Pseudomonas, Azospirillum, Azotobacter, Bacillus and Streptomyces belonged to the microbial population of the tomato rhizosphere under the studied conditions, Azospirillum being the most prominent genus. Artificial inoculation of this rhizobacteria caused a positive effect on seedling growth as well as on plant nutritional stage, the agricultural yield being higher in 11% compared to control plants. A high microbial population level was recorded in the rhizosphere of the inoculated plants.Key words: rhizosphere, inoculant, growth, yield.

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