The egg age of the host Leptoglossus zonatus Dallas (Hemiptera: Coreidae) does not interfere with the parasitism of Gryon gallardoi Brèthes (Hymenoptera: Platygastridae)

Abstract

The age of the host's eggs plays an important role in the reproductive behavior of several species of parasitoids of the genus Gryon. This study investigated whether the age of the eggs of the host Leptoglossus zonatus (Dallas) interferes with the parasitism and emergence of its parasitoid Gryon gallardoi (Brethes). For this, a “cord” of L. zonatus eggs with: 1) 24 hours of age (n=14); or 2) 48 hours of age (n=14) was individually inserted into a test cage. Then, 10 females of G. gallardoi, 24 hours old, mated, without oviposition experience, were released inside the test cage, where they remained for 48 hours. Afterwards, the “cord” of eggs was removed from the cage and inserted into a glass tube and sealed, where it remained for 20 days. Then, the eggs were evaluated for parasitism and adult emergence of the parasitoid. All “cords” of eggs of L. zonatus (n=28 cords), both 24 hours (n=14) and 48 hours of age (n=14), were parasitized by G. gallardoi. Thus, the parasitism rate of G. gallardoi in L. zonatus eggs (n=140 eggs) at 24 hours (88%) and in eggs at 48 hours of age (86%) was similar (χ2 test =0.1 ; gl=1; ns). Similarly, the parasitoid emergence rate also occurred similarly between 24-hour L. zonatus eggs (88%) and 48-hour-old eggs (89%) (χ2 test =0.0; gl =1; ns). Therefore, the age of L.zonatus eggs does not interfere, under laboratory conditions, in the parasitism and emergence of its parasitoid G. gallardoi.