Susceptibilidad de Plutella xylostella (L.) a una cepa colecxtada en campo y una comercial de Beauveria bassiana (Balsamo), bajo condiciones in vitro en Pamplona, Norte de Santander.

Abstract

The objective of this research was to evaluate the mortality of Plutella xylostella (L.), with a strain collected in the field was used and a commercial strain of Beauveria bassiana (Balsamo), under in vitro conditions A strain collected in the field was used and a commercial strain of Beauveria bassiana (Balsamo), were used, with 6 different doses and an absolute control 1x104 CFU/g, 1x105 CFU/g, 1x106 CFU/g, 1x107 CFU/g, 1x108 CFU/g and 1x109 CFU/g. The design was completely randomized and each treatment with 5 replicates and each replicate with 5 second instar larvae (L2), so there were 175 experimental units in each strain. Mortality was evaluated every 12 hours until the death of the moth larvae. The data were analyzed using SPSS software and Tukey tests to determine significant differences between treatments. To calculate the LC50, doses were transformed to log10 and mortalities to Probit, and with the accumulated mortalities and time of death, the TL50 was found by Regression Analysis. The results with respect to the mortality of the A strain collected in the field was used strain show that concentrations from 106 to 109 caused 100% and 104 , 105 caused 92%. The LC50 of the commercial strain is 34,659 CFU/mL, for the A strain collected in the field was used strain it was 118,342 CFU/mL. The TL50 for the commercial strain determined that the concentration of 109 CFU/mL kills 50% of the population at 35 hours, while 104 causes it at 111 hours. The TL50 for the A strain collected in the field was used strain at the concentration of 109 CFU/mL was at 53 hours, while 104 at 73 hours. The results obtained may indicate that the population of P. xylostella L. collected at the Colegio Normal Superior de Pamplona is very susceptible to concentrations of B. bassiana both high and lower than that recommended by the commercial strain.