Soil salinity is considered one of the main abiotic stresses that affect rice cultivation throughout the world. The main objective of this study was to carry out the preliminary agronomic evaluation of five commercial rice varieties (INIAP11, INIAP14, SFL-011, INIAP-FL-Arenillas and Fedearroz-60) under saline soil conditions in Yaguachi, Guayas, Ecuador. A completely randomized block design was used to estimate the agronomic response of the materials by quantifying grain yield t.ha-1 (Yield), number of tillers.m-2 (TN), plant height at harvest (PH), number of panicles.m-2 (NPM), panicle length (PL), number of grains/panicle (NGP), number of filled grains/panicle (NFG), number of vain grains (NVG), weight of 1000 grain (P1000) and content of chlorophyll at 30 (C30D) and 60 (C60D) days. The analysis of variance reflected a high phenotypic diversity among the varieties studied, showing adeq...

Universidad Nacional Agraria La Molina. Escuela de Posgrado. Doctorado en Agricultura Sustentable

Se realizó un estudio en las provincias de Guayas y Los Ríos (Ecuador), con el objetivo de caracterizar los sistemas de producción arrocero; uno en condiciones de salinidad en Yaguachi y otro sin problemas de salinización en el Cantón Babahoyo. Se elaboraron indicadores económicos, sociales y ecológicos, adecuados a los sistemas arroceros bajo estudio para determinar el nivel de sustentabilidad. La evaluación, mediante indicadores, permitió detectar de forma objetiva puntos críticos en estas localidades que afectan la sustentabilidad. En el aspecto ambiental, el indicador salinidad, fue calificado de nivel medio a alto riesgo, el indicador aplicación de agroquímicos, caracterizado por el uso intensivo de plaguicidas y fertilizantes es el que afecta más negativamente la sustentabilidad, especialmente, del sistema arrocero Yaguachi. En la dimensión económica, el indicador si...

This study evaluated the predatory capacity of Orius insidiosus on the mealybug Puto barberi on the campus of the University of Guayaquil, due to the presence of serious phytosanitary problems caused by this insect. Specimens of Orius insidiosus were collected for three months from a nursery at the Vinces Support Center, Los Ríos province, while mealybugs were obtained from ornamental plants (Ixora coccinea) in the green areas of the Ciudadela Universitaria. Trials were established using ½ liter plastic containers with sweet potato cuttings as refuge for O. insidiosus and Ixora coccinea cuttings for the mealybugs; to later introduce the predatory insects. Predation was evaluated at 24, 48 and 72 h. Statistical analysis showed no significant differences between treatments (p-value=0.65). However, it was observed that the percentage of predation accumulated by O. insidiosus (♀) was 31....