RESUMO
The genus Helicoverpa includes several agricultural pests globally. Helicoverpa armigera was reported in several countries in South America in 2013, and in Puerto Rico, in 2014. This territory is considered an agricultural hub, with a high-input system of seed production in the southern region of the island, and also at the edge of the continental U.S. Possible natural dispersion of populations of H. armigera from the Caribbean or other Central American regions poses a continuing risk to the U.S. This study was performed during the post-detection scenario of H. armigera in Puerto Rico, from 2018 to 2021. A year-round pheromone trapping program of adult males indicated an increase in the population from October to March and differences in the occurrence of Helicoverpa spp. between the municipalities Juan Diaz and Salinas. The proportion of H. armigera/H. zea and detection of congeneric hybrids between these species were assessed based on genital morphology and DNA analysis. Interestingly, neither H. armigera nor expected hybrids were detected in the present study. The susceptibility of H. zea populations to the insecticides Spinetoram, Emamectin benzoate, Chlorantraniliprole, and Esfenvalerate was assessed, and an overall significant effect of insecticide susceptibility was detected. Chlorantraniliprole and Emamectin benzoate had the highest efficacy. These results contribute to the Integrated Pest Management and Insect resistance management programs to Helicoverpa spp. in Puerto Rico. In addition, provide validated information to be considered in mitigation plans, in the scenario of an invasion of H. armigera in the continental U.S.
RESUMO
OBJETIVO: El trabajo tuvo como objetivo determinar la eficacia de seis biopreparados locales para el control de las enfermedades foliares del cultivo de la fresa. MATERIALES Y MÉTODOS: Se condujo un experimento en la finca Camacho del municipio de Pamplona Norte de Santander, Colombia. Se utilizó un diseño de bloques al azar con nueve tratamientos, seis biopreparados locales, tres testigos (una saneado, uno sin sanear y un químico). RESULTADOS: Se identificaron como enfermedades foliares más importantes de la fresa a Ramularia tulasnei, Colletotrichum sp., Botrytis cinerea y Xanthomonas fragariae. Los biopreparados Caldo rizósfera y Microorganismos Eficientes (ME) resultaros superiores al tratamiento químico con mancozeb para la mancha por Ramularia. Los bioproductos Caldo Rizósfera y ME mostraron resultados similares que el control químico contra., la pudrición por Botrytis, la mancha por Xanthomonas, y la antracnosis en hojas, flores y frutos, pero los niveles de incidencia de esta enfermedad estuvieron entre 46 y 55 % en flores y entre 56 y 63 % en frutos. CONCLUSIONES: Los biopreparados Caldo Rizósfera y ME resultaros superiores al tratamiento químico con Dithane para mantener a la mancha por Ramularia en niveles de severidad aceptables, al igual que a la mancha bacteriana y la pudrición por Botrytis y resultaron similares que el control químico contra la antracnosis en hojas, flores y frutos, sin embargo, los niveles de incidencia en flores y frutos de la antracnosis no son los deseados, amenazando la rentabilidad del agricultor
OBJECTIVE: The work aimed to determine the efficacy of six local biopreparations for the control of leaf diseases of strawberry cultivation. MATERIALS AND METHODS: An experiment was conducted at the Camacho farm in the municipality of Pamplona Norte de Santander, Colombia. A randomized block design was used with nine treatments, six local biopreparations, three controls (one sanitized, one unsanitary and one chemical). RESULTS: The most important foliar diseases of the strawberry were Ramularia tulasnei, Colletotrichum sp., Botrytis cinerea and Xanthomonas fragariae. The biopreparations Rhizosphere Broth and Efficient Microorganisms (ME) are superior to the chemical treatment with mancozeb for the spot by Ramularia. The bio-products Rhizphere Broth and ME showed similar results that the chemical control against Botrytis rot, Xanthomonas spot, and anthracnose on leaves, flowers and fruits, but the incidence levels of this disease were between 46 and 55% in flowers and between 56 and 63% in fruits. CONCLUSIONS: The biopreparations Rhizphere Broth and ME were superior to the chemical treatment with Dithane to maintain the spot by Ramularia at acceptable levels of severity, as well as the bacterial spot and Botrytis rot, and although they were similar to the chemical control against anthracnose in leaves, flowers and fruits, however, the levels of incidence anthracnose in flowers and fruits are not desired, threatening the profitability of the farmer
