TITLE:
Sublethal Doses of Insecticides Affect the Fecundity and Fertility of the Chrysodeixis includens?
AUTHORS:
Raimundo Henrique Ferreira Rodrigues, Luciana Barboza da Silva, Thiago Ferreira Rodrigues, Gleidyane Novais Lopes, Eliane Carneiro, Bruno Ettore Pavan
KEYWORDS:
Bacillus thuringiensis, Chemical Control, Indoxacarb, Soybean Looper, Teflubenzuron
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.9 No.3,
February
27,
2018
ABSTRACT: The objective was to determine lethal concentrations
and to evaluate the effects of sublethal doses of insecticides on Chrysodeixis includens under laboratory conditions. The standard population of C. includens was kept on artificial diet under controlled conditions (25°C ± 5°C, 60% ± 10 RU, 12:12 h). The active principles used were B. thuringiensis, Indoxacarb and Teflubenzuron. The CL25 and LC50 obtained
from dose response curve (estimated from eight concentrations of each active principle)
were diluted in water and applied to the back of third instar caterpillars and compared
to the control (water). The insecticides used showed lethal and sublethal effects
in C. includens. Bacillus thuringiensis was 6.21 and
2.79 times more toxic to soybean looper
when compared to the products Indoxacarb and
Teflubenzuron, respectively. Insecticides applied to the caterpillars reduced
survival and affected the biomass gain with increased larvae and pupae longevity,
with a significant reduction in fertility (40%) and fecundity (94.97%) in adults.
In the present study it was observed that both survival and larval biomass gain
have a direct effect on fecundity and fertility, respectively. Therefore the active
ingredients Indoxacarb, Teflubenzuron
and B. thuringiensis can be used in rotation as a tool in the C. includens.