Intraguild predation and cannibalism among Dicyphini: Dicyphus cerastii vs. two commercialized species

Abstract

Dicyphine mirids are one of the most important groups of predators on tomato. In the Mediterranean region, several species in the genera Dicyphus, Macrolophus, and Nesidiocoris (Hemiptera: Miridae, Bryocorinae, Dicyphini) colonize protected horticultural crops. In Portugal, Nesidiocoris tenuis (Reuter) is increasingly abundant in the mirid species complex of tomato crops and appears to be displacing the native Dicyphus cerastii Wagner. In order to know whether intraguild predation (IGP) can explain the decreasing abundance of D. cerastii, we evaluated predatory interactions between adult females and first instars of D. cerastii vs. N. tenuis but also D. cerastii vs. Macrolophus pygmaeus (Rambur), as this species is also naturally present in horticultural crops in Portugal. Cannibalistic interactions were also tested for the same three species. All experiments were performed under laboratory conditions, in Petri dish arenas, in the presence or absence of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs as alternative prey. Predation on both heterospecific and conspecific nymphs occurred only in the absence of alternative food. Intraguild predation was mutual and symmetrical between D. cerastii and M. pygmaeus. However, IGP was asymmetrical between D. cerastii and N. tenuis, favouring the first. Cannibalism was not significantly different among these mirid species. Our results show that D. cerastii has a greater capacity to feed on intraguild prey than N. tenuis. Therefore, IGP on small nymphs does not explain the abundance shift between D. cerastii and N. tenuis.

Functional Response and Predation Rate of Dicyphus cerastii Wagner (Hemiptera: Miridae)

“…Therefore, an insight into predator preferences may help to understand and predict the efficacy of D. cerastii in multiple prey situations. Dicyphines can also present cannibalistic and intraguild predatory interactions [87,88]. Both these direct, and indirect interactions such as competitive displacement [31], may also affect the success of biological control programs with these predators.…”

Egg Cannibalism Varies With Sex, Reproductive Status, and Egg and Nymph Ages in Arma custos (Hemiptera: Asopinae)

“…Many Hemiptera insects are known for their cannibalistic behavior, such as Arizona backswimmers Frank (Zalom, 1978), Triatoma infestans Klug and Triatoma sordida Stal (Ryckman, 1951), Arctocorisa carinata and Callicorixa producta (Pajunen and Pajunen, 1991), Xylocoris flavipes Reuter (Richard, 1979), Notonecta hoffmanni (Orr et al, 1990), Dicyphus cerastii Wagner, and Macrolophus pygmaeus Ranmbur (Goncalo et al, 2020) which would prey on its immature offspring. Our previous research showed that female A. custos were more active predators (ate more eggs than males) (Wu et al, 2020), while males did not participate in egg cannibalism.…”

Entomophagous insects – an introduction

“…Aspects of predator behavior are addressed by Duarte et al (2021) who report on intraguild predation (IGP) and cannibalism within Dicyphini (Hemiptera: Miridae). Predaceous mirids are common in horticultural crops and some species are also released for biological control, which might displace naturally occurring species.…”