Functional Response of Microplitis croceipes and Cardiochiles nigriceps (Hymenoptera: Braconidae) to Variation in Density of Tobacco Budworm (Lepidoptera: Noctuidae)

1996 ◽  
Vol 25 (2) ◽  
pp. 524-528 ◽  
Author(s):  
P. Glynn Tillman
1999 ◽  
Vol 34 (2) ◽  
pp. 249-259 ◽  
Author(s):  
D. W. Atwood ◽  
T. J. Kring ◽  
S. Y. Young

Bacillus thuringiensis Berliner var. kurstaki and thiodicarb were evaluated in laboratory and field assays to determine the effect on tobacco budworm larvae, Heliothis virescens (F.), and the parasitoid Microplitis croceipes Cresson. Laboratory trials were conducted using B. thuringiensis concentrations of 0, 10, 50 and 250 ppm and thiodicarb concentrations of 0, 12.5, 25, 50, 100, and 200 ppm in the diet. The test using field-treated cotton squares was conducted using B. thuringiensis and thiodicarb, independently and in combination, at rates recommended for resistance management in Arkansas. Laboratory tests indicated that tobacco budworm mortality was directly related to B. thuringiensis and thiodicarb concentrations, although B. thuringiensis only significantly increased tobacco budworm mortality at the highest concentration of exposure in the absence of parasitization. Parasitization increased host mortality at all B. thuringiensis experimental rates after 6 and 14 days. Although host mortality increased linearly with increasing thiodicarb concentration, parasitization did not significantly increase host mortality over thiodicarb alone until day 14. Emergence of M. croceipes was inversely related to B. thuringiensis and thiodicarb concentration. In assays using squares from field-sprayed cotton, thiodicarb and thiodicarb/B thuringiensis mixtures provided significantly greater tobacco budworm mortality than did B. thuringiensis application alone. In addition, no significant advantage was determined for tank mixtures with B. thuringiensis as compared to thiodicarb application alone. However, neither B. thuringiensis nor thiodicarb, alone or in combination, caused a high mortality of early third instar tobacco budworm in the absence of parasitization by M. croceipes.


2015 ◽  
Vol 148 (1) ◽  
pp. 112-117 ◽  
Author(s):  
Agustín Hernández-Juárez ◽  
Luis A. Aguirre-Uribe ◽  
Aideé González-Ruíz ◽  
Julio C. Chacón-Hernández ◽  
Jerónimo Landeros-Flores ◽  
...  

AbstractThe effect of the insecticide endosulfan on the predatory efficiency of the green lacewing, Chrysoperla carnea Stephens (Neuroptera: Chrysopidae) on the eggs of tobacco budworm, Heliothis virescens (Fabricius) (Lepidoptera: Noctuidae) and fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) was measured with Holling’s disc equation. Though the type II functional response was maintained in C. carnea exposed to endosulfan, the functional response parameters: attack rate (a′), handling time (Th), total handling time (Tht), searching time (Ts), and search efficiency (E) were affected for both prey offered. The predator took more time to identify, pursue, capture, consume, and digest the prey, and in general, the efficiency of the predator as a biological control agent was adversely affected.


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