Host defensive response against an egg parasitoid involves cellular encapsulation and melanization

Quality assessment of Riptortus pedestris (Hemiptera: Alydidae) eggs cold-stored at different temperature and relative humidity regime

“…O. nezarae showed lower parasitism on host eggs stored at 10°C, and their progeny showed longer development times and a higher male proportion as compared to eggs stored at 2 or 6°C. Lower parasitism of eggs stored at 10°C could be due to viability of the host, causing a loss of nutrients for parasitoids to exploit, or may be due to a defense mechanism of the viable host embryo (Reed et al, 2007). Storage temperature also affected the body size of adult progeny, with a decrease in body size at 10°C.…”

Innate immunity: Eggs of Manduca sexta are able to respond to parasitism by Trichogramma evanescens

“…Nevertheless, we cannot exclude that also some parasitoid eggs commit suicide and die, but also this parasitoid apoptosis might be induced by host factors. Interestingly, a very recent study of an encyrtid egg parasitoid of two closely related cerambycid beetles revealed by microscopic analyses that one of the cerambycid species could encapsulate the parasitoid larva inside the host egg within 72 h after parasitization, while the other one was unable to do so (Reed et al, 2007). Both this study of parasitism of cerambycid eggs and our study of parasitism of Manduca eggs show that insect eggs do not always surrender once they are attacked by parasitoids, but instead have means to cope with parasitoid attack.…”

Development of a Strategy for Selective Collection of a Parasitoid Attacking One Member of a Large Herbivore Guild

“…However, the parasitoids obtained from the marked P. recurva egg masses used in this study carried out in southern New South Wales must be a different strain from the wasps that were collected from southern Victoria in the early and mid-1990s, and mass reared and released in California to control P. semipunctata, because the latter strain has a strong innate preference for P. semipunctata over P. recurva eggs from our laboratory colonies, and it has much higher survival rates in P. semipunctata eggs than in P. recurva eggs (Luhring et al 2000(Luhring et al , 2004Reed et al 2007). Host egg preference and suitability experiments comparing the two strains are in progress under quarantine condi- a Number of egg masses and number eggs laid are the numbers of egg masses and numbers of eggs found when the cages were opened.…”

“…During investigations into the possible causes of this remarkable replacement of one species by a congener, we discovered that the strain of the egg parasitoid A. longoi that had been so effective for control of P. semipunctata in California was apparently poorly adapted to and much less effective against P. recurva (Luhring et al 2000(Luhring et al , 2004Paine et al 2004;Reed et al 2007). In particular, when given a choice, A. longoi from our mass-rearing colonies showed a strong preference for eggs of P. semipunctata.…”

“…In particular, when given a choice, A. longoi from our mass-rearing colonies showed a strong preference for eggs of P. semipunctata. Furthermore, eggs of P. recurva were frequently able to encapsulate and kill the parasitoid eggs and produce a beetle larva, whereas eggs of P. semipunctata showed no sign of encapsulation of the parasitoid eggs, nor did any P. semipunctata egg ever survive parasitism and produce a neonate larva (Luhring et al 2000, Reed et al 2007). The preference and suitability were innate, because even after forced rearing of this A. longoi strain exclusively on P. recurva eggs for Ͼ15 generations, when given a choice, the wasps still preferred and had much greater rates of survival on eggs of P. semipunctata (Luhring et al 2004).…”