Trichilia hirta, ON, ON

García-Gómez, A., Figueroa-Brito, R., García Serrano, L. A. & Jiménez-Pérez, A., 2018, Trichilia (Meliaceae) plants: an important source of biomolecules with insecticidal properties, Florida Entomologist 101 (3), pp. 470-470 : 470-

EFFECT OF THE EXTRACTS OF TRICHILIA HIRTA ON COPITARSIA DECOLORA SURVIVAL

Mean larval survival time was significantly affected by T. hirta bark hexane extracts (Log-Rank Test = 33.43; df = 4; P <0.001; Table 2 ; Fig. 3a ). Larvae fed the 1,500 ppm treatment had the shortest mean survival time; however, this was not significantly different from those fed the 1,000 and 500 ppm treatments. Larval mortality was over 50% except at 100 ppm. The highest cumulative mortality occurred in the 1,500 ppm diet, and no adults were obtained from this treatment.

Mean survival time of C. decolora larvae was not affected by T. hirta bark ethyl acetate extract (Log-Rank Test = 7.227; df = 4; P <0.124). This varied from 28.8 ± 3.4 d at 1,500 ppm treatment to 33.6 ± 1.6 d for the control diet treatment. The highest larval and cumulative mortalities were recorded in the 1,500 ppm treatment, and exceeded 60%.

Trichilia hirta bark acetone extracts significantly affected the mean survival time of C. decolora larvae (Log-Rank Test = 13.886; df = 4; P <0.008; Table 2 ; Fig. 3b ). The shortest mean survival time was recorded in the 1,500 ppm concentration; however, this treatment was significantly different only from the control diet treatment. The highest larval, pupal, and cumulative mortalities were recorded in the 1,000 ppm treatment.

Methanol extract significantly reduced mean larvae survival time (Log-Rank Test = 17.523; df = 4; P <0.002; Table 2 ; Fig. 3c ). Larvae on the 1,500 and 1,000 ppm concentration had the shortest mean survival times and differed only as compared to the control diet treatment. The highest larval, pupal, and cumulative mortalities were recorded in 1,500 ppm treatment.

Aqueous extracts had a significant reduction in mean larvae survival times in all the concentrations as compared to the control diet treatment (Log-Rank Test = 76.205; df = 4; P <0.001; Table 2 ; Fig. 3d ), with the 1,500 ppm treatment the shortest of all. All insects died as larvae before 21 d of age ( Fig. 3d ).

Figures

Fig. 3. Survival curves of Copitarsia decolora larvae fed on an artificial diet supplemented with extracts of Trichilia hirta bark at 100, 500, 1,000, and 1,500 ppm: (a) hexane, (b) acetone, (c) methanol, and (d) aqueous.