Utilization of Quercetin as an Oviposition Stimulant by Lab-Cultured Coleomegilla maculata in the Presence of Conspecifics and a Tissue Substrate

Abstract

Background: The discovery of natural products to improve the reproductive performance of mass-reared predators is an important aim for successful augmentative biological control. We tested the hypothesis that quercetin (a bioflavonoid) stimulates oviposition by the ladybird beetle Coleomegilla maculata in the presence of conspecifics and a tissue substrate. Methods: We conducted bioassays in solitary cages (housing one female) and communal cages (housing 10 females) to estimate daily oviposition site preferences, egg production in response to quercetin in the presence or absence of a tissue paper substrate, and female “resting” positions. Results: Females preferentially oviposited within 1–2 cm of quercetin powder, held in a tiny dish, at the base of cages. When given a choice, females oviposited in the dish with quercetin over a tissue paper substrate. In one of two experiments, they produced more egg clutches, regardless of oviposition site, when the quercetin and tissue were in close juxtaposition. Females “rested” on the tissue in the presence or absence of quercetin. Conclusion: This study provides evidence that quercetin can be utilized as an oviposition stimulant by C. maculata in a rearing system. Future research should determine if quercetin stimulates oviposition in other ladybird beetle species.

Effects of Three Artificial Diets on Life History Parameters of the Ladybird Beetle Stethorus gilvifrons, a Predator of Tetranychid Mites

“…According to our findings, DHBA (a weak oviposition stimulant) increased progeny production in S. gilvifrons. Several phenolic compounds including DHBA, quercetin, taxifolin, and naringenin have stimulated oviposition behavior in the aphidophagous coccinellid, C. maculata, in the laboratory [40,47,48].…”

Volatile and Non-Volatile Organic Compounds Stimulate Oviposition by Aphidophagous Predators

“…In a follow-up study, quercetin altered C . maculata oviposition behavior in 1 L lab cages, housing 10 females, even in the presence of a preferred oviposition substrate, such as white tissue paper [ 18 ]. Lastly, a final study tested the effectiveness of 2,4-dihydroxybenzoic acid (DHBA), which is a degradation product of the flavonoid morin, to stimulate oviposition by C .…”

“…In summarizing this section, the discovery of high molecular weight, non-volatile organic compounds (non-VOCs) such as the flavonoids quercetin and taxifolin as oviposition stimulants for lab-reared C . maculata was novel, because this coccinellid had no prior exposure to either compound [ 17 , 18 ]. Are olfactory receptors important in detection of non-VOCs?…”

“…Are olfactory receptors important in detection of non-VOCs? Female coccinellids must touch or taste non-VOCs such as flavonoids and flavonoid derivatives before oviposition stimulation can occur [ 17 , 18 , 33 ], suggesting that olfactory receptors have a limited role in detection of non-VOCs and oviposition stimulation in coccinellids. Yet, one coccinellid species, H .…”

Potential of 2,4-Dihydroxybenzoic Acid as an Oviposition Stimulant for Mass-Reared Ladybird Beetles

“…A major challenge to mass rearing predators in high quantities is stimulating females to oviposit their full potential of eggs when reared on alternative foods (Riddick 2009; Sun et al 2017; Riddick et al 2018a,b). Also, chemical cues that females use to choose oviposition sites are often associated to natural prey, e.g., aphids and/or host plants under natural conditions in the field (Honĕk 1980, Hodek and Evans 2012).…”