Selectivity of Insecticides Against Adult Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) on Cassava

Abstract

In this study, the effects of various chemical and biological insecticides on adults of the parasitoid species Trichogramma pretiosum (Riley) were examined in cassava. The chemical insecticides zeta-cypermethrin, lufenuron + profenofós, imidacloprid, thiamethoxam, and teflubenzuron and the biological agents Bacillus thuringiensis and Baculovirus erinnyis were evaluated. For each treatment group, the effects were evaluated using T. pretiosum mortality rates, longevity of females, the number of eggs parasitized by the F0 generation, and number of emergent F1 parasitoids. The insecticides were classified using the International Organization for Biological Control categories. The tested insecticides had little effect on longevity and survival of adults, but all affected parasitism (F0) and were moderately harmful to the parasitoid. In relation to the emergent (F1) generation, the pesticides were either harmless or slightly harmful, except for zeta-cypermethrin which was classified as harmful with a 100% reduction in parasitoid emergence. The results indicate that the tested insecticides were moderately harmful to T. pretiosum in the laboratory; future studies will examine the effects of the insecticides under semi-field and field conditions to confirm their toxicity.

Compatibility between Entomopathogenic Fungi and Egg Parasitoids (Trichogrammatidae): A Laboratory Study for Their Combined Use to Control Duponchelia fovealis

“…Previous research has shown that confirmed fungus-related mortality depends on the virulence of fungal strains, EF species, Trichogramma species, and the application period (pre- or post-parasitism) [ 22 , 27 , 39 ]. Furthermore, the interactions between the EF and Trichogramma species were minimal for all biological parameters considered in this study, especially when compared with chemical insecticides [ 11 , 43 , 44 , 45 ].…”

“…Indeed, they are involved in pest control programs for over 200 insect species [8]. In particular, members of the Trichogrammatidae family have considerable potential as cost-effective control agents against Lepidoptera pests due to their ability to be easily mass-produced [8][9][10][11][12]. However, the use of non-selective pesticides in agricultural production systems limits the successful implementation of biological control programs that use Trichogrammatidae species due to the sensitivity of these organisms [11].…”

“…In particular, members of the Trichogrammatidae family have considerable potential as cost-effective control agents against Lepidoptera pests due to their ability to be easily mass-produced [8][9][10][11][12]. However, the use of non-selective pesticides in agricultural production systems limits the successful implementation of biological control programs that use Trichogrammatidae species due to the sensitivity of these organisms [11]. Moreover, pesticide application can negatively affect beneficial arthropods, cause toxicity to humans, and may contaminate the final crop products, thus becoming especially relevant for those that are consumed in fresh, such as fruits and vegetables, including strawberries [13].…”

Selectivity of mycoinsecticides and a pyrethroid to the egg parasitoid Cleruchoides noackae (Hymenoptera: Mymaridae)

“…Natural enemies are important in pest control in planted forests, justifying the search for compatible microbial and chemical products 18 . The mycoinsecticides and chemical insecticides must have selectivity to the pest natural enemies 19,20 in order to maintain the effectiveness of the combined use of these methods.…”

Selectivity of insecticides with two active ingredients on the parasitoid >i<Trichogramma pretiosum>/i< (Hymenoptera: Trichogrammatidae)

“…The best way to reduce their population to a noneconomic-injury level is through a combination of control methods, as in Integrated Pest Management (IPM). It is important to guarantee that the control methods, when used together, do not compromise the effectiveness of each other(Oliveira et al 2013, Torres and Bueno 2018, Feltrin- Campos et al 2019. Therefore, an important step for integrating biological and chemical control is the evaluation of the pesticide selectivity.…”