Ensayos de campo para la mejora de la eficacia de las trampas de captura de Rhynchophorus ferrugineus, Olivier (Coleóptera: Dryophthoridae), picudo rojo de la palmera

espanolEl proposito de esta investigacion fue determinar primero la capacidad de migracion del insecticida thiamethoxam 25% inyectado en el tronco de palmeras datileras y segundo establecer la eficacia de este tratamiento para el control quimico de la cochinilla roja de la palmera datilera (Phoenicococcus marlatti, Cockerell). Se estudio, asi mismo, la tolerancia del cultivo al producto, a las dosis ensayadas, y al metodo. El ensayo se realizo en una parcela de palmeras datileras donde fueron seleccionadas 15 palmeras con un alto grado de infestacion de la plaga. Se realizaron cinco tratamientos en bloques randomizados con tres repeticiones cada uno: 3 dosis diferentes de thiamethoxam 25% (2.5, 5 y 10 g/palmera) aplicado por inyeccion al tronco, mas un tratamiento control con diazinon 24% pulverizado directamente a las hojas y un testigo sin tratar. Se estudio la mortalidad de la cochinilla roja, realizando conteos en las hojas jovenes, a los 40 dias del tratamiento. Para evaluar la migracion del insecticida por la palmera, se analizaron mediante test Elisa muestras de la base del tronco y de las hojas de las palmeras tratadas con thiamethoxam 25%. Los resultados muestran una gran efectividad de thiamethoxam 25% en el control de P. marlatti a las tres dosis administradas. Esta efectividad ha sido estadisticamente superior al tratamiento control con diazinon 24%. En las palmeras tratadas con thiamethoxam 25% no aparecio ningun sintoma de fitotoxicidad. En cuanto a la migracion del producto por el interior de la palmera, este consigue llegar tanto a las hojas mas jovenes como a las maduras, e incluso descender a la base del tronco. EnglishThe purpose of this investigation was to determine first the migration capacity of 25% thiamethoxam and secondly the effectiveness of the applications of this insecticide by trunk injection for the chemical control of the red scale of the date palm (Phoenicococcus marlatti, Cockerell). In the same time, the objective was to control the eventual phytotoxicity of the product at the doses that have been tested. The experimentation was carried out in a parcel of date palms where were selected 15 palms with a high grade of infestation of the pest. Were carried out five treatments in randomized blocks with three repetitions each one: 3 different doses of thiamethoxam 25% (2.5, 5 and 10 g/palmera) applied by injection to the trunk, more a treatment control with diazinon 24% sprayed directly to the leaves and a control without any treatment. The mortality of the red scale was studied by carrying out counts on the young leaves, 40 days after the treatments. The migration of the insecticide in the palm was also evaluated by analyzing, by means of test Elisa test, samples of the base of the trunk and of the leaves of palms treated with 25% thiamethoxam. The results demonstrate a great effectiveness of 25% thiamethoxam in the control of P. marlatti at the three doses that have been tested. This effectiviness has been statistically superior to the control treatment with 24% diazinon. In the palms treated by injection of 25% thiamethoxam, no phytotoxicity symptom has appeared. Regarding the migration of the product in the interior of the palm, it has been established that the product migrates to the youngest leaves as well as to the mature ones, and even is capable to go down to the base of the trunk, although with a certain variability.