Integrated Pest Management for Stored Grain: Potential Natural Biological Control by a Parasitoid Wasp Community

Abstract

Insect contamination of stored grain is a major concern for the grain industry. Phosphine is currently the standard fumigant used to control insect pests in stored grain. However, some species and populations of insects that infest stored grain exhibit resistance to this fumigant and consumers are concerned about pesticide residues. Therefore, alternative methods of effective pest control are needed to partially or completely replace the use of phosphine. There is growing interest in biological control via parasitoid wasps. However, there is evidence that biological control will succeed only if used alongside other pest-management measures. Integrating biological control with the use of chemical insecticide is challenging and may lead to severe reductions in parasitoid survival and success. The main aim of the current study is to shed light on a greatly overlooked issue: the parasitoid community found in stored grain before and after phosphine treatment. The current study results indicate that there is a high level of parasitoid biodiversity within grain stores. We found common parasitoids at both semi-arid and Mediterranean sites, suggesting that those parasitoids can be active across a wide range of abiotic conditions. This research indicates that the community may recover even though phosphine has an immediate negative effect on a parasitoid community. Nevertheless, the parasitoid wasps seem to reduce the host population insufficiently. In light of the findings presented here, those interested in implementing pest-management strategies that include both phosphine treatment and biological control should consider conservation and augmentation of the naturally occurring parasitoid population. These studies should take into account interactions between and within parasitoid populations and phosphine distribution within the grain storage. To limit the effect of phosphine on the parasitoids, pest-management strategies should also reflect careful consideration of the timing of phosphine treatment and the need for sufficient refuge for the parasitoids.

Study on natural enemy composition and effectiveness to control pupa and adult of Oriental fruit fly (Bactrocera dorsalis) in star apple (Chrysophyllum cainito) using entomopathogenic fungi

“…It has already been applied to reducing the population of Ceratitis capitata in mangoes (Wong et al, 1991; Sanchez et al, 2016) [22,18] . Bactrocera dorsalis (Hendel) (Vargas et al, 2012) [20] , Anastrepha obliqua (Macquart), and Anastrepha ludens (Loew) (Montoya et al, 2000) [15] , and it proposed as a potential natural biological control (Harush et al, 2021) [11] . The investigation results showed that the natural enemies of fruit flies in the orchard were abundant (Fig.…”

Genome assembly of the ectoparasitoid wasp Theocolax elegans

“…In comparison, biological control using natural enemies presents a safer and more biorational approach. Currently, parasitoid wasps from Pteromalidae, Bethylidae, Braconidae and Ichneumonidae have been reported as natural enemies of many important stored product pests, and several species have been sensibly utilized in the control of insect pests in storehouses 6 – 8 . Parasitoids suppress host immunity by injecting virulence factors including venom during oviposition, and the progeny consume and eventually kill the hosts, effectively, sustainably and safely controlling the host population 9 , 10 .…”

Dynamic Economic Thresholds for Insecticide Applications Against Agricultural Pests: Importance of Pest and Natural Enemy Migration

“…Warehouses are generally fumigated with phosphine once per year (Vidan et al 2020). The pests support a community of several species of naturally occurring parasitoid wasps (Harush et al 2021). Based on local economic parameters (Supp Table 1 [online only]), and local insecticide efficiency of 99%, the EIL (Eq.…”