Puccinia striiformis f. sp. tritici (Pst) causes wheat stripe rust (also called yellow rust, Yr), one of the most important diseases worldwide. Characterization of virulence in Pst populations is essential for developing wheat cultivars with effective and durable resistance to control the disease. A total of 138 Pst races, including 120 races that were not previously reported, were identified from stripe rust collections made from Canada, China, Ecuador, Egypt, Italy and Mexico in 2013-2020 using a set of 18 Yr single-gene differentials. Virulence of the resistance gene Yr5 or Yr15 was not found in isolates from any of the countries, indicating their effectiveness against the Pst populations. Virulence to 16 Yr genes was detected, but the frequencies varied greatly among countries. On average, the frequencies of virulence to Yr6, Yr7, Yr9, Yr43, Yr44 and YrExp2 were high (81.7-90.6%), those to Yr1, Yr8, Yr17, Yr27, YrSP and Yr76 were moderate (34.0-56.8%), and those to Yr10, Yr24, Yr32 and YrTr1 were low or very low (0.4-18.5%). The same races detected in different countries and different races from different countries clustered into the same virulence groups, indicating Pst migration among different countries, especially between eastern Asia and the Mediterranean region. These results should be useful for breeding wheat cultivars with effective resistance to stripe rust in these countries as well as globally.

In Ecuador, the reduction of forests is evident, so it is necessary to evaluate fast-growing forest species that can meet growing demands, avoiding deforestation in areas where forests of the region are still maintained. The objective was to evaluate the growth of three species of the genus Paulownia in three localities of the Ecuadorian Coast as a medium-term alternative for productive and afforestation purposes. Diameter, height and volume were evaluated in three locations with two planting frames for three Paulownia species (Paulownia fortunei Hemsl; Paulownia elongata SYHu; Paulownia hibrido and a control (Gmelina arborea Roxb) with three replications. Data were recorded in the second year of planting. The Paulownia species were surpassed by G. arborea in the evaluated variables. In the humid tropics localities, there was no statistical difference between Paulownia species contrasting with the dry tropics locality in which P. eloganta in the 3 x 3 m plantation frame that presented the best values. Paulownia species did not exceed the control. The best results were achieved in the localities of Los Ríos and Santo Domingo; however, they should not be considered an alternative for productive purposes and afforestation in the humid tropics of Ecuador.

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El aguacate es una fruta tradicional en la dieta de los ecuatorianos y requiere un manejo adecuado que garantice su producción. La implementación de nuevas alternativas tecnológicas, como utilización de índices de espectroscopia, permite obtener datos que al correlacionarlos optimizarán el manejo del cultivo. Esta investigación validó el uso de índices vegetales basados en la banda roja e infrarrojo cercano con el contenido de nitrógeno foliar. Se utilizó los índices vegetales: índice normalizado diferencial de vegetación (NDVI) e índice de vegetación transformado (TVI) desde dos ortomosaicos obtenidos mediante imágenes que capturan banda roja e infrarrojo cercano en plantaciones de aguacate.  Se realizaron regresiones y correlaciones entre los índices vegetales y los resultados de los análisis foliares de contenido de nitrógeno, generando valores de R² de 0,93 para NDVI y 0,95 para TVI. Los valores de los índices vegetales pueden utilizarse para estimar el vigor de la planta basado en el contenido de nitrógeno foliar.