Effect of three insecticides on the life cycle of Aphidius uzbekistanicus Luz. (Hym., Aphidiidae)

Abstract

The effects of two pyrethroids and one organophosphorous broad s ectrum insecticides were tested in laboratory conditions on the main European parasitoid of the cereafaphids at the recommended rates. The 3 compounds were found to kill both the host aphid and its parasitoid when living parasitized aphids were sprayed. When the mummies were sprayed, the number of emergences was significantly reduced by dimethoate and deltamethrin. The longevity and the percentage of females in the F1 offsprings was reduced by all 3 insecticides and the number of offsprings from emerged adults was only reduced by dimethoate. When adults were in contact with either pyrethroid during one hour, their longevity was reduced and the sex ratio of their offsprings became unbalanced in favour of males.

Effect of Contact Pesticides on Vine Mealybug Parasitoids, Anagyrus sp. near pseudococci (Girault) and Coccidoxenoides perminutus (Timberlake) (Hymenoptera: Encyrtidae)

“…Consequently, parasitoid mortality could result or their performance adversely affected (Wang et al, 2008). Mortality of parasitoids at the time of emergence has been documented for adults of aphid parasitoids (Hsieh & Allen, 1986;Krespi et al, 1991;Lingren et al, 1991;Islam & Copland, 1997;Walton & Pringle, 1999). Low mortality of C. perminutus when exposed to fipronil and α-cypermethrin could be due to a different mechanism of exiting the mummy case.…”

The influence of unspraying on diversity of soil‐related hymenopteran parasitoids in cereal fields

“…Furthermore it has been shown that access to food sources of nectar and pollen may increase the longevity, fecundity and attack rates of adult parasitoids (SYME. 1975;FOSTER and RUESINK, 1984), and in this respect flowering weeds have shown to increase the number of parasitized host (ALLEN and SMITH, 1958;LEIUS, 1967;TOPHAM and BEARDSLEY, 1975;FOSTER and RUESINK, 1984;BARCZAK, 1991).…”

“…The use of pesticides is an integrated part of the agricultural routines, and since parasitoids in general are regarded as beneficials some attention has been payed to the influence of pesticides on these non-target invertebrates. The susceptibility of such insects to pesticides has been shown in laboratory experiments (HAS-SAN 1983;NATON, 1983;KRESPI et al, 1991). Similarly, comparisons between pesticide treated and untreated fields or plots have revealed reduced numbers of parasitoids in treated areas (POWELL et a]., 1984;GREIG-SMITH, 1990).…”

Evidence of potential long term effects in (aquatic and terrestrial) invertebrates after short term pulsed exposure. Literature reviews on ecotoxicology of chemicals with special focus on plant protection products

“…Brachonidae) to the OP dimethoate at a concentration equivalent to 400 g a.s./ha reduced adult parasitoid longevity by more than 90%, and resulted in the decrease of successful aphid infection to 0, as did a 10-minute exposure of adults to the same concentration (Krespi, et al 1991).…”