Efecto de la inoculación con bacterias rizosféricas en dos variedades de trigo. Fase I: condiciones controladas

The experiment was carried out in a greenhouse so that the inoculation, both simple and combined (with the rhizospheric bacteria- Sinorhizobium and Azospirllium), en two varieties of Wheat. Materials and methodologies were used in accordance with previously prescribed conventional methodologies for this study. The experimental design was completely randomized, with 4 replicas and 10 treatments. A statistical analysis using two-way variance was done. Fertilized treatment was applied with NH4NO3 (150 ppm/kg soil). The content of chlorophyll foliage was evaluated, dry air weight, dry root weight, length of stem, and germination. In the event that differences appeared, it was determined through use of the Duncan Test, and the differences between varieties with t-Student. It is concluded that combined inoculation with the strain A2 (Sinorhizobium meliloti) and the strain N7 (Azospirillum zeae) had the greatest positive influence on the chlorophyll content of the plants. On the other hand, there was a great difference between the two varieties of wheat in terms of length of stem, dry air weight, and dry root weight. The results of dry air weight and dry root weight, upon combining the two factors that were studied, highly depended on the varietal characteristics of the plant and on the native population of rhizobacteria. The germination of the plants was not linked to any of the applied factors in the experiment.Se llevo a cabo un experimento bajo condiciones controladas para determinar la respuesta de dos variedades de trigo a la inoculacion simple y combinada realizada con Sinorhizobium y Azospirillum. Se utilizo una cepa de A. zeae, y dos cepas pertenecientes a S. meliloti. Los materiales y metodos aplicados correspondieron a lo descrito en las metodologias prestablecidas en este campo de estudio. Diseno experimental: completamente aleatorizado, con 20 tratamientos y 4 replicas. No se utilizo tratamiento fertilizado. Se evaluaron diferentes variables agronomicas, relacionadas con la arquitectura radical y la biomasa aerea. Analisis de varianza bifactorial. En caso de aparecer diferencias, se aplico analisis de varianza de un factor a la interaccion en primera instancia, o a los factores probados. Diferencias entre medias por LSD de Fisher. Se transformaron datos de conteo de digitos por �ãx. Se calculo correlacion y regresion multiple entre variables. Se concluye que la inoculacion combinada de Sinorhizobium con Azospirillum, asi como la inoculacion simple con Sinorhizobium, resultaron de alta importancia en las alternativas de inoculacion que se realizaron en el experimento. Existio una alta diferenciacion entre las dos variedades de trigo en determinadas variables agronomicas, lo que indica una influencia marcada de las caracteristicas varietales de las plantas. Se observó una fuerte relación estadística entre las variables peso seco aéreo y variables de la raíz para los tratamientos inoculados con A2 y A2+N7, respectivamente

Inoculación de Andropogon gayanus Kunth con Glomus cubense y Azospirillum brasilense en presencia de estrés por sequía

Objective: To evaluate the response of Andropogon gayanus Kunth to inoculation with Glomus cubense and Azospirillum brasilense , in the presence of drought stress. Materials and Methods: In an established area of A. gayanus , an establishment cutting was performed after seed harvest and inoculation was done with EcoMic® (Glomus cubense) and INICA-8. The experimental design was a complete randomized block, with seven treatments and eight replicas. The treatments consisted of: EcoMic® immediately after cutting, INICA-8 immediately after cutting, INICA-8 + EcoMic® immediately after cutting, EcoMic® at cutting+ INICA-8 (15 days), INICA-8 at cutting + EcoMic® (15 days), absolute control and fertilized control (150 kg N/ha, NH3NO4). The dry weight of the aerial part, stem length, length of the flowering section of the stem, length of the inflorescence, dry weight of the racemes and flowering were evaluated. Variance analysis was performed. Differences among means were determined by Fisher’s LSD. Results: Area dry weight was higher (p < 0,0001) in the fertilized control than in all treatments (12 036,1 kg/ha). The EcoMic® (9 612,5 kg/ha), EcoMic®+INICA-8 (8 475,0 kg/ha) and EcoMic® (cutting)+INICA-8 (15 days) treatments were superior to the absolute control (6 822,2 kg/ha), as well as to the other inoculated treatments. The EcoMic®+INICA-8 treatment showed statistical superiority in stem length (189,7 cm), raceme dry weight (0,071 g) and flowering (0,4462 %). EcoMic® (cutting)+INICA-8 (15 days) was higher in inflorescence length (16,39 cm) and in length of the flowering section of the stem (56,08 cm), although the fertilized control did not differ from these treatments. Conclusions: The single application of INICA-8 had no higher effect on any of the studied variables. However, EcoMic®, at the time of cutting, alone or combined with Azospirillum, was determinant in most of the variables. These results prove the importance of the application of EcoMic® in this crop under drought stress conditions, as well as the synergy among the microorganisms that were inoculated, when combined with each other due to a higher effect on the plan

Efecto de la inoculación con bacterias rizosféricas en dos variedades de trigo. Fase II: invernadero

The experiment was carried out in a greenhouse so that the inoculation, both simple and combined (with the rhizospheric bacteria- Sinorhizobium and Azospirllium), en two varieties of Wheat. Materials and methodologies were used in accordance with previously prescribed conventional methodologies for this study. The experimental design was completely randomized, with 4 replicas and 10 treatments. A statistical analysis using two-way variance was done. Fertilized treatment was applied with NH4NO3 (150 ppm/kg soil). The content of chlorophyll foliage was evaluated, dry air weight, dry root weight, length of stem, and germination. In the event that differences appeared, it was determined through use of the Duncan Test, and the differences between varieties with t-Student. It is concluded that combined inoculation with the strain A2 (Sinorhizobium meliloti) and the strain N7 (Azospirillum zeae) had the greatest positive influence on the chlorophyll content of the plants. On the other hand, there was a great difference between the two varieties of wheat in terms of length of stem, dry air weight, and dry root weight. The results of dry air weight and dry root weight, upon combining the two factors that were studied, highly depended on the varietal characteristics of the plant and on the native population of rhizobacteria. The germination of the plants was not linked to any of the applied factors in the experiment.Se llevó a cabo un experimento de invernadero para evaluar la influencia de la inoculación simple y combinada, efectuada con las bacterias rizosféricas Sinorhizobium y Azospirillum, en dos variedades de trigo. Materiales y métodos según lo descrito en las metodologías convencionales para este campo de estudio. El diseño experimental fue completamente aleatorizado, con 4 réplicas y 10 tratamientos. Análisis estadístico varianza bifactorial. Se utilizó tratamiento fertilizado con NH4NO3 (150 ppm/kg suelo). Se evaluó contenido de clorofila foliar, peso seco aéreo, peso seco radical, longitud del tallo y germinación. En caso de aparecer diferencias, se determinaron mediante la prueba de Duncan, y las diferencias entre las variedades con t-Student. Se concluye que la inoculación combinada de la cepa A2 (Sinorhizobium meliloti) con la cepa N7 (Azospirillum zeae), fue la de mayor influencia positiva en el contenido de clorofila de las plantas. Por otra parte, existió una alta diferenciación entre las dos variedades de trigo en la longitud del tallo, peso seco aéreo y peso seco radical. Los resultados en peso seco aéreo y peso seco radical, al combinarse los dos factores estudiados, dependieron notablemente de las características varietales de la planta y del efecto significativo de la población autóctona de rizobacterias. La germinación de las plantas no estuvo vinculada a ninguno de los factores aplicados en el experimento