Laboratory developmental traits and functional response of Pseudapanteles dignus (Hymenoptera: Braconidae) attacking Tuta absoluta (Lepidoptera: Gelechiidae) in eggplant.

SALAS GERVASSIO N.G; LUNA M.G; PEREYRA P.C; D´AURO F.; SÁNCHEZ N.E

Congreso; XVIII International Plant Protection Congress; 2015

Laboratory studies were carried out to investigate some developmental traits and functional response of Pseudapanteles dignus (Muesebeck), a larval endoparasitoid of Tuta absoluta (Meyrick) in eggplant, Solanum melongena L., other crop attacked by this pest. Stage specific developmental times were evaluated by exposing 10 2nd and 3rd T. absoluta larvae to P. dignus wasps. Egg-pupal developmental time was similar for males ((13.74 ±0.66 d ) and greater for females (13.57 ± 0.4 d) than when reared on T. absoluta in tomato. Pupal stage was longer for both sexes (~ 13 d) in eggplant, yielding a longer total preimaginal period for this parasitoid in eggplant than in tomato crops. To determine P. dignus potential efficiency to control T. absoluta in eggplant crops, the parasitoid functional response to varying host densities (3, 7, 10, 15 and 20 2nd and 3rd ?instars larvae; 24 h- exposition period, 8 replicates per host density) was assessed. As in tomato, P. dignus showed a density independent type I response in laboratory (only significant p0 = -1.39 ± 0.4 SE) in S. melongena, but attacked a lower number of hosts per day (attack rate (a?) =0.19 ± 0.03 SE, 95 % CI 0.13-0.24). These results suggest that P. dignus has an inferior performance when reared on S. melongena, which could have implications for use in biological control of T. absoluta in eggplant.