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The research was carried out in El Carmen canton, Manabí province, Ecuador. The objective was to evaluate the effect of levels of poultry manure on the chemical properties of an Inceptisol soil dedicated to the production of fine aroma cocoa (Theobroma cacao L.) with the use of corn (Zea mays L.) as indicator plant. Soil samples were taken in 2017 with a completely randomized design and levels 0, 2, 4, 4, 6 and 8 t ha-1 to be applied per 1.5 kg pots of soil. Comparisons of means were performed according to Tukey's test for p≤0.05 and Pearson’s correlation matrix with the statistical processors SPSS, Statistics (Version 19.0 on Windows) and STAHTGRAPHICS Plus, version 5.0. The best level of poultry manure was 6 t ha-1 since the highest pH value (water) and the lowest acidity of change, the highest Ca/Mg ratio and the highest percentage of organic matter were achieved in the soil, and the best foliar nutrient contents (%), Ca/Mg ratio and total dry matter were achieved in the plant. The results showed positive correlations between the percentage of organic matter, foliar Ca/Mg ratio and root dry matter, and between assimilable phosphorus contents in the soil and total dry matter. [ABSTRACT FROM AUTHOR]

The aim of this work was to determine the antagonistic effect of the endophytic endosporeforming bacteria against M. roreri, as well as its identification. The trial was carried out by dual culture method on Petri dishes containing Potato Dextrose Agar culture medium (PDA). The bacterial inoculum was placed in the center of the plate, and discs of the pathogenic fungus were placed on both sides of the plate. M. roreri colony growth was measured and the radial growth inhibition percentage (RGIP) was calculated at 15 days. A completely randomized design was used with five replicates per treatment (isolate from endophytic bacteria) and control (M. roreri). Besides, bacteria were characterized from the cultural, morphological and physiological point of view according to methodologies collected in the scientific literature. In the antagonism test, 23 isolates of the bacteria (51.1 %) showed a RGIP in the pathogen ranging from 53.8 to 73.8 %; while 22 isolates (48.9 %) registered a RGIP between 2.8 and 47.2 %, at 15 days of incubation in the interaction. The description of the bacterial isolates based on their cultural and morpho-physiological characteristics confirmed their taxonomic location in the group of the aerobic endospore-forming bacteria, class Bacilli. It is demonstrated the high potential of new strains of Bacillus spp. as promising candidates for the biological control of M. roreri, which is the causal agent of frosty pod rot. [ABSTRACT FROM AUTHOR]

El presente trabajo se realizó con el objetivo de actualizar el estado de información existente sobre los microorganismos endófitos asociados a Theobroma cacao L. como agentes de control biológico de la moniliasis, causada por Moniliophthora roreri Evans et al. Se resume sobre el origen y evolución de las definiciones de microorganismos endófitos, enfatizando en el control biológico de las enfermedades del cacao con énfasis en la moniliasis, uno de los problemas fitosanitarios de mayor importancia a nivel mundial; así como se hace una valoración sobre sus perspectivas de empleo. Los hongos y bacterias endófitos presentan varios mecanismos de acción entre los que se encuentran: competencia directa por el espacio y nutrientes, antibiosis, micoparasitismo, resistencia sistémica inducida y promoción del crecimiento; funciones que son parte de las estrategias para el manejo eficaz y sostenible de la moniliasis. The present work was carried out with the objective of updating the state of existing information on the endophytic microorganisms associated with Theobroma cacao L., as agents of biological control of moniliasis, caused by Moniliophthora roreri Evans et al. It is summarized on the origin and evolution of the definitions of endophytic microorganisms, emphasizing the biological control of cocoa diseases with emphasis on moniliasis, one of the most important phytosanitary problems worldwide; as well as an assessment of their employment prospects. Fungal and bacterial endophytes have several mechanisms of action, which include direct competition for space and nutrients, antibiosis, mycoparasitism, induced systemic resistance and promotion of growth; functions that are part of the strategies for an effective and sustainable management of the frosty pod rot. [ABSTRACT FROM AUTHOR]