Characterization of the vegetal growth promoting capacity of Tsukamurella paurometabola C-924 and the main mechanisms involved
Abstract
The Tsukamurella paurometabola C-924 strain, previously isolated from banana rhizosphere as antagonist of phytoparasitic nematodes, was shown to display other beneficial effects in plants. This work was aimed at determining its growth-promoting activity, and characterizing the main mechanism involved in this process. It was confirmed that T. paurometabola C-924 displays growth-promoting activity in plants through various mechanisms. Therefore, under the tested conditions, T. paurometabola C-924 was able to release indoleacetic acid, solubilize phosphate, produce ammonia from organic matter and release lytic exoenzymes, which may protect plants during the attack of phytopathogens. Its compatibility with other soil microorganisms used as biofertilizers (Rhizobium leguminosarum, Pseudomonas fluorescens and Azotobacter chrococcum) was also tested, favoring the colonization process of mycorrhizogen fungi and stimulating the formation of arbuscular mycorrhizae. It was further determined that T. paurometabola C-924 stimulates the development of economically relevant crops, such as: beans, corn, banana and lettuce, by increasing height, structuring of the radicular system, foliage and dry weight. This was the very first report ever on the growth promoting activity of T. paurometabola, and also in the Tsukamurella genera, describing the processes involved. That strain bears potentialities for application as biofertilizer in different agricultural systems. This research granted the 2013 Award of the Cuban National Academy of Sciences.
