Triticum aestivum requires nitrogen fertilizer (NF) as NH4NO3 for healthy growth, however its excessive application causes loss of soil fertility. An alternative to decrease the amount of NH4NO3 and to optimize is to inoculate T. aestivum seeds with Xanthobacter autotrophicus or/and Bacillus thuringiensis well known asendophytic plant growth promoting bacteria (EPGPB). Both genera and species of EPGPB are able transform metabolic compounds from seeds and roots into phyto hormones, which can be optimized by crude extract carbon nano particles (CECNPs) to enhance the growth of radical system and to improve uptake at 50% dose of NH4NO3 Response variables were: germination percentage, phenology, and biomass to seedling stage. All experimental data were validated by ANOVA/Tukey HSD P<0.05. Seeds of T. aestivum were inoculated with X. autotrophicus and/or B. thuringiensis, plus CECNPs at 50% NH4NO3. Results showed a positive response of T. aestivum seeds to X. autotrophicus and/or B. thuringiensis, with 10 ppm CECNPs, and 50% NH4NO3 enhanced germination percent of 93% in comparison with 73% of T. aestivum when its seeds were not inoculated with these EPGPB fed only with 100% dose of NH4NO3 (relative control); the same positive response of T. aestivum to X. autotrophicus and B. thuringiensis improved by CECNPs at seeding stage compared to T. aestivum used as a relative control.

En suelos secos la supervivencia del género y especies de Azotobacter, es paralela a la de otros grupos microbianos nativos como actinomicetos y hongos de ese ambiente, dependiente de la capacidad de adaptación genética de cada uno, en combinación con algunas de las propiedades fisicoquímicas del suelo, y de las condiciones ambientales de almacén. Los objetivos de este trabajo fueron: i) analizar la supervivencia de Azotobacter en suelo recién colectado y almacenado por 11 y 30 años ii) caracterizar bioquímicamente Azotobacter vinelandii aislado estos suelos iii) dinámica de supervivencia de actinomicetos, bacterias y hongos en los suelos. Para cual cada uno de los suelos se conservó por distinto periodo de tiempo en contenedores de vidrio estériles a temperatura ambiente, de ahí diluyeron para cuantificar cada grupo en: agar nutritivo para bacterias, agar de caseína almidón para actinomicetos, agar Rosa de Bengala para hongos y agar Burk para Azotobacter. Los resultados mostraron que el número de Azotobacter supervivientes en el suelo almacenado por 30 años fue de 12 x 10 6 UFC/g, de 52 x 10 6 UFC/g en suelo seco por 11 años y de 300 x 10 6 UFC/g de suelo seco recién colectado. En el suelo de 30, 11 años se detectó una densidad de Azotobacter spp., inferior al suelo seco recién colectado. Se encontró diferencia en los perfiles bioquímicos de A. vinelandii de suelo almacenado por 30 años, en comparación el mismo género y especie en el recién colectado. Lo que anterior indica que las propiedades fisicoquímicas del suelo, el periodo de desecación fue crítico en la supervivencia de Azotobacter y de los otros grupos de microorganismos nativos de ese ambiente. Journal of the Selva Andina Research Society ® . Bolivia. Todos los derechos reservados.

The well-known bacteria genus called as Bacillus thuringiensis (Bt) is recognized for being used in the biological control of insect pests in agriculture. However, there is little information on the effect of Bt as a plant growth promoter and in interaction with Micromonospora echinopora, which, being an endophyte, could improve the response of Phaseolus vulgaris with NH4NO3 atreduced at 30%of common recommended without risk of affecting plant health or yield.The objective of this work was to analyze the response of P. vulgaris to Bt and M. echinospora with NH4NO3 at 30% of recommended dose. The experiment was conducted under a randomized block design, using the response variables: germination percentage, phenology and biomass. The experimental data were analyzed by ANOVA/Tukey HSD (P<0.05). In the results, it was found that B.thuringiensis induced in P. vulgaris a yield of 3.2Ton/Ha, while with M. echinospora 3.6Ton/Ha was reached, with NF reduced at 30%, while it was shown that B.thuringiensis improved the yield with M. echinospora with 4.0Ton /Ha, values with statistical difference compared to the 2.8 Ton/Ha of P. vulgaris without B.thuringiensis or M. echinospora used as relative control with 100% of the NF.Concluded that B. thuringiensis is not only useful in biological control but that it can be an excellent growth promoter that can be improved with M. echinospora, another option for the sustainable production of P. vulgaris.