Entomopathogenic fungi (EF) are recognized biological control agents of insects. Basically, the entomopathogenic fungi pathogen activity depends on the ability of its enzymatic equipment, consisting of lipases, proteases and chitinases, which are in charge of breaking down the insect's integument. Lipases are the first enzymes synthesized by the entomopathogenic fungi. Recently, a cytochrome P450 subfamily, referred as CYP52XI and MrCYP52 has been identified in Beauveria bassiana and Metarhizium robertsii, respectively. These break down long-chain alkenes and fatty acids to become initial nutrients. Subsequently, subtilisin type (Pr1) proteases sintetize; these enzymes are considered as virulence indicators and they are regulated by a signal transduction mechanism activated by the protein kinase A (PKA) mediated by AMPc. Through the employment of genetic engineering, it has been possible to increase virulence producing Pr1 recombinants with Androctonus australis neurotoxins or with chitinases, reducing the insect's time of death. In the course of time, the Pr1 protease gene has presented evolutionary adaptations by gene duplication or horizontal transfer infecting different orders of insects. In the same way, the entomopathogenic fungi chitinases have presented a functional diversification. Currently, these have been phylogenetically classified into three subgroups, in accordance to the catalytic site domain and the chitin binding domain. The chitinolytic activity has increased through a directed evolution processes and genetic recombination with Bombyx mori chitinase. Recently, enzymes have been employed as control agents for insects and phytopathogenic fungi (disease originator) opening new potentialities in order to improve the entomopathogenic fungi use. Solid state fermentation is a bioprocess that would produce at great scale enzymes and some other metabolites in grade of increasing the entomopathogenic fungi virulence, in the control of insects and potentially in some

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Plant extracts can be used as an alternative to synthetic insecticides for the control of insect pests. Based on this knowledge, juvenomimetic and insecticidal activities of n-hexane extracts of the aerial parts of Senecio salignus DC. (Asteraceae) and Salvia microphylla Kunth (Lamiaceae) collected in Mexico were evaluated against 1st instar larvae of Spodoptera frugiperda Smith & Abbot (Lepidoptera: Noctuidae). Senecio salignus extract showed insecticidal activity at 500 ppm, resulting in larval mortality of 52.5% and pupal mortality of 62.5%. Salvia microphylla extract at the same concentration caused larval mortality of 65.0% and pupal mortality of 82.5%. The LC50 was 440 ppm for S. salignus extract and 456 ppm for S. microphylla extract based on the total larval period. The juvenomimetic activity of S. salignus extract at 500 ppm increased the duration of the larval period to 17.3 d and of the pupal period to 1.4 d. It also reduced pupal weight by 34.7% with respect to the control (241 mg). For S. microphylla extract at 500 ppm, the duration of the larval and pupal periods were increased by 2.0 and 12.1 d, respectively, and the pupal weight was reduced by 14.1% with respect to the control (243 mg). The major compounds of S. salignus extract were γ-sitosterol, palmitic acid, lupeol, and β-amyrin, and those of S. microphylla extract were oleic acid, γ-sitosterol, (Z,Z,Z)-9,12,15-octadecatrien-1-ol, and palmitic acid. These results indicate that both extracts have potential to be used to control S. frugiperda due to their juvenomimetic and insecticidal activities.

The application of enzymatic extracts and conidia of Beauveria bassiana in Metamasius spinolae and Cyclocephala lunulata was evaluated. The variables were mortality and time of death. In M. spinolae, mortality with extracts 29%, conidia 27% and the combination of both 31%, all had a time of death of four days. Although with different symptoms, used enzymatic extracts: contraction and softening of the joints; by conidia: mycelium in the joints; in the combination of conidia and enzymatic extracts: abundant aerial mycelium. In C. lunulata, 100% mortality in all treatments; Time of death: enzymatic extracts and extracts with conidia 1.2 days; conidia 2.8 days. Symptoms were different, enzymatic extracts: melanization and internal tissue lysis; enzymatic extract and conidia: mycelium emerged and melanization; conidia: mycelium emerged. Enzymatic extracts showed insecticidal activity in M. spinolae and C. lunulata. These results suggest the potential of enzymatic extracts as biocontrol agents to improve the use of entomopathogenic fungi.

Introducción: Bradysia impatiens causa pérdidas significativas en viveros e invernaderos de México.Objetivo: El efecto insecticida e insectistático de Beauveria bassiana se evaluó sobre B. impatiens.Materiales y métodos: El efecto insecticida e insectistático de conidios (107 conidios·mL-1), enzimas (10 000 ppm), metabolitos (10 000 ppm) y extracto crudo de B. bassiana se evaluó a los 8 y 20 días. Los datos de mortalidad corregida de larvas y pupas de B. impatiens y emergencia relativa de adultos, transformados con la función arcoseno, se sometieron a un análisis de varianza y comparación de medias de Tukey (P < 0.05).Resultados y discusión: En el día 8, los conidios tuvieron la mayor actividad insecticida con 31.1 % de mortalidad corregida, mientras que la actividad de las enzimas fue nula. A los 20 días, los tratamientos de metabolitos y conidios tuvieron el mayor efecto en la mortalidad, 47.5 y 42.1 %, respectivamente. Dichos tratamientos tuvieron la mayor actividad insectistática. La emergencia de adultos a los 20 días fue menor con los conidios (6 %), mientras que con las enzimas fue de 100 %. Los metabolitos provocaron que 65 % de los adultos mostraran malformaciones.Conclusión: Los metabolitos y conidios de B. bassiana podrían emplearse para el control de larvas y pupas de B. impatiens.