Patogenicidad de diferentes aislamientos del género Beauveria sobre larvas de Loxotoma elegans (Lepidóptera: Elachistidae), defoliador de la palma de aceite en los Llanos Orientales

The Loxotoma elegans insect is an oil palm leaf eater and it is consider one of the most important pests in the East Colombian region. The aim of this study was to identify efficient Beauveria isolates to control L. elegans larvae. The trial was carried out at the Aceites Manuelita laboratory condition. A complete randomized design was used, with 12 treatments, and four replications. The experimental unit was 35 larvae of L elegans from 6th to 8th instars. Among the treatments 10 were Beauveria isolates, one was the application of Tween 80 at 1% and the last one was control treatment. Suspension of 1?L from each treatment was applied to each larva. The effectiveness of each treatment was measured on larval mortality and sporulation percentage. Mortality percentage correction was done with Schneider-Orelli equation. Larva mortality evaluations were done every three days and larval sporulation every two days, over a period of 18 days. Six isolates presented more than 80% of larva mortality. The isolates ?B035? and ?B045? showed to be 100% effective on affecting L elegans larvae, whereas, ?B018? and ?B021? isolates had 90% of larvae mortality. The ?B035? and ?B045? isolates showed 95,8% and 81,7% sporulation respectively. However ?B018?, ?B021?, ?B039? and ?B019? isolates had low sporulation with 64.81% in the first case and for the other isolation measurements the sporulation did not exceed 50%. The isolates ?B045? and ?B035? were selected as potential treatment to control L. elegans larvae, because those isolates presented quick pathogenic activity and more than 80% sporulation, which indicate the high potential to be effective in field.