Efecto Insecticida del Extracto de Semillas de Neem (Azadirachta indica A. Juss) sobre Collaria scenica Stal (Hemiptera: Miridae)

This work was developed with the objetive to evaluate the insecticidal effect of the Neem (Azadirachta indica A. Juss) seeds against grass bug nymphs Collaria scenica Stal. For that, an extract was prepared from green fruits of Neem by rotaevaporación. The extract was diluted in three ppm concentrations corresponding to treatments. Using thin-layer chromatography we identified the presence of Azaridactina. DCA essay was carried out with 4 treatments and 5 repetitions that included the three extract concentrations and a control. In each repetition were used 15 nymphs, randomly placed in plastic boxes with food and the corresponding concentration. Every day an extract application was made and recorded mortality percentage, number of exuviae and number of individuals who came to adulthood in each treatment. The results were analyzed using Kruskal-Wallis and Games-Howell for each variable. The three concentrations of Neem seed extract had a negative effect on the development of the bugs. The more concentrated treatment (250 ppm) was the most effective, showing a 97% mortality, fewer exuvias and and fewer adults in the end of the experimentEl presente trabajo se desarrollo con el objetivo de evaluar el efecto insecticida del extracto etanólico de semillas de Neem (Azadirachta indica A. Juss) sobre ninfas de la chinche de los pastos Collaria scenica Stal. Para eso, se elaboró un extracto a partir de frutos inmaduros de Neem mediante rotaevaporación. El extracto fue diluido en tres concentraciones de ppm que corresponden a los tratamientos. Por medio de cromatografías en capa delgada se determinó la presencia de Azaridactina. Se realizó un experimento DCA de 4 tratamientos y 5 repeticiones que incluyó las tres concentraciones del extracto y un control. En cada repeticion se usaron 15 ninfas, colocadas aleatoriamente en cajas plásticas herméticas con alimento y la concentración correspondiente. Diariamente se realizó una aplicación del extracto y se registró porcentaje de mortalidad, número de exuvias y número de individuos que llegaron al estado adulto en cada tratamiento. Los resultados fueron analizados con prueba Kruskal-wallis y Games-Howell para cada variable. Las tres concentraciones del extracto de semillas de Neem presentaron un efecto negativo sobre el desarrollo de las chinches. El tratamiento más concentrado (250 ppm) fue el más eficaz presentando una mortalidad del 97%, menor número de exuvias y menor número adultos al final del ensay

Efecto Insecticida del Extracto de Semillas de Neem (Azadirachta indica A. Juss) sobre Collaria scenica Stal (Hemiptera: Miridae)

This work was developed with the objetive to evaluate the insecticidal effect of the Neem (Azadirachta indica A. Juss) seeds against grass bug nymphs Collaria scenica Stal. For that, an extract was prepared from green fruits of Neem by rotaevaporacion. The extract was diluted in three ppm concentrations corresponding to treatments. Using thin-layer chromatography we identified the presence of Azaridactina. DCA essay was carried out with 4 treatments and 5 repetitions that included the three extract concentrations and a control. In each repetition were used 15 nymphs, randomly placed in plastic boxes with food and the corresponding concentration. Every day an extract application was made and recorded mortality percentage, number of exuviae and number of individuals who came to adulthood in each treatment. The results were analyzed using Kruskal-Wallis and Games-Howell for each variable. The three concentrations of Neem seed extract had a negative effect on the development of the bugs. The more concentrated treatment (250 ppm) was the most effective, showing a 97% mortality, fewer exuvias and and fewer adults in the end of the experiment