Biology of Dineulophus phtorimaeae (Hymenoptera: Eulophidae), and field interaction

LUNA, M.G.; WADA, V.I.; SÁNCHEZ,

ANNALS OF THE ENTOMOLOGYCAL SOCIETY OF AMERICA

ENTOMOLOGICAL SOC AMER

Año: 2010 vol. 103 p. 936 - 942

0013-8746

Some biological characteristics of the ectoparasitoid Dineulophus phtorimaeae (de Santis) (Hymenoptera: Eulophidae) and field interaction with the endoparasitoid Pseudapanteles dignus (Muesebeck), both larval parasitoids of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), were examined. Additionally, we completed the original D. phtorimaeae description. Preimaginal developmental time of the ectoparasitoid was 11. 17 ± 0.60 d for both sexes, and adult life span took 11.73 ± 0.92 d for females, and  8.78 ± 0.93 d for males. The proportion of sexes was equal. In the field, hosts were parasitized at the third-larval instar. On average, a female attacked ca. four hosts throughout its lifetime, and deposited eggs in approximately 50% of cases. The most successful female attacked six hosts, yielding a potential fecundity of ca. 10 eggs. Host paralysis without parasitism was observed, suggesting stinging for host feeding. The daily oviposition curve is compatible with a synovigenic-type parasitoid. Our prediction stating that D. phtorimaeae would succeed when competing for hosts with P. dignus was correct, since it had greater parasitism rates. In the field, both T. absoluta parasitoids were able to coexist at the scale of the individual leaf. Differences in feeding behavior, a narrower host range (third instar) and a lower fecundity of D. phtorimaeae, would be compensated by its better attributes as natural enemy, in comparison to P. dignus, making possible their coexistence.