Acta Scientiarum. Agronomy
On-line version ISSN 1807-8621
ANDRADE, Lígia Helena de et al. Effects of botanical insecticides on the instantaneous population growth rate of Aphis gossypii Glover (Hemiptera: Aphididae) in cotton. Acta Sci., Agron. [online]. 2012, vol.34, n.2, pp. 119-124. ISSN 1807-8621. http://dx.doi.org/10.4025/actasciagron.v34i2.10863.
Botanical insecticides have been studied aiming the alternative pest control. The present study investigated the effects of these insecticides on the instantaneous population growth rate (ri) of Aphis gossypii. Botanical insecticides were tested in the following concentrations: Compostonat®, Rotenat-CE® and Neempro (0, 0.50, 0.75, 1.00, 1.25, 1.50 and 1.75%); Natuneem® and Neemseto® (0, 0.25, 0.50, 0.75 and 1.00%) and essential oils of Foeniculum vulgare Mill., Cymbopogom winterianus (L.), Chenopodium ambrosioides L. and Piper aduncum L (0, 0.0125, 0.025, 0.0375 and 0.05%). Cotton leaf discs, CNPA 8H cultivar with 5 cm in diameter were immersed for 30 seconds in products broth and dried for 30 minutes. Eight replicates per concentration were used and each disc was infested with five apterous adult females of A. gossypii uniform in size and confined for 10 days. Compostonat®, Rotenat® and Neempro provided negative ri decreasing A. gossypii population. Natuneem® and Neemseto® and the essential oil of F. vulgare showed positive ri increasing the population. The coefficients of determination (R2) of regression lines ranged from 0.46 to 0.85. The essential oils of C. winterianus, C. ambrosioides and P. aduncum were not statistically significant precluding the establishment of regression lines.
Keywords : cotton aphid; bioactivity; Gossypium hirsutum; natural insecticides.