The activity of various biofertilizers on rice production (Sabanero A95) was evaluated in Palizada, Campeche, Mexico, in the wet season of 2009 (year one) and 2011 (year two). On year one, arbuscular mycorrhiza INIFAP ® (Rhizophagus intraradices), Azospirillum brasilense plus arbuscular micorrhiza Rhizophagus sp., and chemical fertilizer (92, −92, −60 kg•ha −1) were evaluated, while on year two marine algae extracts, a consortium of growth promoting bacteria (Pseudomonas spp.) and a control (not fertilized) were evaluated. The results showed that there were no significant differences on grain yield among treatments during the year one. The average grain yield was 2,800 kg•ha −1. As for the year two, the highest grain yield was observed on plots fertilized with chemical fertilizer (3333 kg•ha −1), followed by plots treated with mycorrhiza INI-FAP ® (3000 kg•ha −1). The economic analysis for rice production in both years showed that the use of arbuscular mycorrhiza decreases the cost of production by 18.5% and 16.3%, which suggests that microbial inoculants might be good substitutes of chemical fertilizers in rice production.

The Salvia hispanica L. is an endemic species Mexican plant, which relevance relies upon its properties as a natural source of omega 3 (α-linolenic acid), soluble and insoluble fibers, proteins, plus some other significant nutritional components. Due to the growing relevance generated by this crop, it became necessary to characterize its physical environment, as well as the natural factors related with its cultivation nationwide, aiming to find those most suitable for its production under rainfed conditions, looking forward to provide the basis to make a decision regarding where to target the agriculture promotion of such cropland. The software used for data process and analysis was the Arc/View 3.3 version. Thus, the crop requirements were recognized in order to analyze those most suitable for chia development in each one of its selected variables in the study hereby. The regionalization and mapping aimed to detect both the optimal and suboptimal potential areas for such crop were carried out, afterwards. It was finally determined that Mexico holds a total of 2,512,359 hectares with an optimal or high cultivation potential, whereas the areas with a medium or suboptimal potential are close to 3,658,089 hectares, which can be set under rainfed conditions.

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Las hojas son el órgano más importante en la planta de Stevia rebaudiana Bertoni, debido a que en ellas se encuentra la mayor cantidad de edulcorante. La emisión de hojas está determinada por el adecuado crecimiento de raíces y la cantidad de agua disponible en el suelo. El objetivo del presente estudio fue evaluar la respuesta de plantas de S. rebaudiana Bert. a cuatro láminas de riego calculadas a partir de la evapotranspiración de referencia (ETo) en interacción con inoculantes microbianos. Los tratamientos consistieron en regar con el 60, 80, 100 y 120% de la ETo estimada con un tanque evaporímetro tipo “A” en plantas previamente inoculadas.  Se evaluaron como inoculantes una mezcla de Bacillus spp. y Azospirillum brasilense, Rhizophagus intraradices y un testigo (sin inocular). Se utilizó un diseño de bloques completos al azar con arreglo bi-factorial y cuatro repeticiones. Se evaluaron parámetros de crecimiento, producción y distribución de biomasa seca, intercambio de gases y uso eficiente del agua. Se encontró diferencia estadística (P?0.05) por factores separados. Se obtuvo la mejor altura con 120% ETo, aunque fue estadísticamente igual (P?0.05) a 100% ETo registrando 42.86 y 40.58 cm respectivamente, el 120% ETo se registró mayor área foliar. El tratamiento con Rhizophagus intraradices mostró diferencias significativas (P?0.05) en la longitud de raíz contra el testigo, pero no contra la mezcla de rizobacterias. De igual forma R. intraradices mejoró el volumen de raíz registrando 2.49 cm3 con respecto al testigo, y permitió reducir un 20% la aplicación de la ETo para obtener la mayor producción de biomasa seca de hoja y raíz. La interacción R. intraradices + 80% ETo favoreció la asimilación del CO2 con 5.41 µmol m-2 s-1, de esta manera se proporcionó mejores condiciones para la transpiración y el uso eficiente del agua (1.87 µmol CO2 mmol-1 H20). El factor riego mostró efecto en la altura, área foliar, diámetro del tallo y rendimiento de hoja seca, mientras que el factor inoculante sólo afectó la longitud de raíz, volumen de raíz, relación MSV/MRS y rendimiento. Por último, la interacción de los dos factores solo fue significativa en los parámetros de producción de biomasa seca e intercambio de gases. 

There are many advantages to using liquid cultures for the production of blastospores. These include mainly the processes of scale up which are relatively easy, as well as the control of parameters such as temperature, aeration and pH. In this work, we evaluated the production of Paecilomyces fumosoroseus blastospores using a low-cost liquid culture medium in a fermenter in comparison to a medium commonly used for this purpose, with regard to yield and viability of blastospores. The two media contained the same concentration of glucose but differed in N source (M1 containing casamino acids and M2 provided with collagen peptone and yeast extract). Starting with an inoculum of 1x10 6 blastospores/ml, M2 medium produced 2x10 10 blastospores/ml after incubation for 72 h at 520 rev/min agitation and 1 v/v/m (volume air/volume liquid.min) aeration, while only 2.4 x 10 8 /ml were produced with M1. In addition, the microorganisms in medium M1 grew more slowly during log phase and reached an earlier plateau at 36 h fermentation. The medium containing collagen peptone and yeast extract is an excellent alternative for the production of P. fumosoroseus blastospores, providing lower cost, higher yield and shorter propagation time, but formulation does need to be improved.