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Effect of host deprivation on reproductive potential of the arrhenotokous species (Trichogramma euproctidis Girault and T. bourarachae Pinturaeau and Babanlt) and Thelytokous species (T. cordubensis Vargas and Cabello) (Hymenoptera: Trichogrammatidae), originated from strains collected from olive farms in Egypt, was studied. Upon emergence, females were deprived of hosts for one to four days and were subsequently provided daily with unlimited eggs of Sitotroga cerealella Olivier (Lepidoptera: Gelechiidae) for parasitisation. As deprivation time increased, total number of parasitized hosts by T. euproctidis, T. borarachae and T. cordubensis decreased from an average of 73.2±2.7, 80.1±3.5 and 61.7±2.6, when hosts were provided on emergence, to an average of 37.6±0.7, 38.4±0.5 and 34.5±1.2, when waiting time was 4 days, respectively. This reduction was mainly due to the reduction in the parasitisation, following the first laying peak, which was not affected when deprivation lasted fewer than 2 days. The longer deprivation, is the lower daily parasitisation. The arrhenotokous females produced significantly more progeny than thelytokous females, regardless to the period of host deprivation. Obtained results indicated that the efficacy of Trichogramma females as biological control agents may be sensitive to host deprivation which is likely to occur in nature. [ABSTRACT FROM AUTHOR]

The agromyzid leaf miners, Liriomyza trifolii (Burgess) and L. bryoniae (Kaltenbch) (Diptera: Agromyzidae) were found as major pests attacking faba bean (Vicia faba) in Alexandria, Egypt. A survey of their parasitoid species was carried out in 2012/13 and 2013/14 faba bean growing seasons. Parasitoid adults emerged from infested samples with the leaf miners were collected. Seven hymenopterous parasitoid species, belong to the families Braconidae and Eulophidae, were recorded; two braconids; Pseudopzomochus masii Nixon and Opius basalis (Fischer) and five eulophids; Diglyphus isaea (Walker), Chrysocharis pentheus (Kamijo), Halticoptera circulus (Walker), Halticoptera sp. and Zagrammosoma sp. Among the parasitoids surveyed , P. masii was recorded for the first time from Liriomyza spp. in Egypt; its sex ratio was female biased in all collected samples. D. isaea was the most predominant parasitoid species found, accounting 68.3 and 41.4% of the total parasitoids emerged in 2012/13 and 2013/14 seasons, respectively. It was active throughout the growing season and increased in number as the leaf miners' population increased. P. masii came next after D. isaea, particularly in the second season. Natural suppression of Liriomyza spp. by parasitoids seemed to be important for maintaining Liriomyza populations below damaging levels. [ABSTRACT FROM AUTHOR]

Comparative study of parasitic capacity and longevity of three local Trichogramma spp.; T. cordubensis and T. euproctidis from arid area and T. borarachae from a semi-arid area, collected from olive groves in Egypt, was carried out under laboratory conditions at 25±0.5°C. Significant differences were found among the parasitic capacity of the tested Trichogramma spp. It was 80.1±3.5 for T. borarachae versus 60.2±2.5 for T. cordubensis and 73.2±2.7 for T. euproctidis. In all species, parasitism was highest in the first day. Longevity of Trichogramma females was studied by exposing freshly emerged wasps to different feeding regimes as follows: 1) combination of honey and host eggs, 2) honey only and 3) no honey or hosts. The longevity experiments indicated that feeding conditions significantly affected the survival period of the wasp females. In all species, the longevity of honey-fed non ovipositing females was significantly longer. In the absence of food source all species showed the shortest longevity. In general, parasitoid longevity under each feeding condition was species dependent. [ABSTRACT FROM AUTHOR]

The poor survival of EPNs storage is one of the main factors that prevent them from realizing their full potential as bioinsecticides. Of several EPNs isolates, two effective Heterorhabditis spp. isolates and/or strains (N169 and 195) were selected to study the storage stability of their infective juveniles (IJs) and conducting bioassay test of the EPNs during storage period at room temperature (23±2°C) (February-April). Survival rate of IJs in control (water) was significantly lower compared with those stored in vermiculite or calcium alginate granules (gel granules) and significantly higher in calcium alginate granules than in vermiculite. Both isolates had higher survival rates in calcium alginate granules than in vermiculite. At room temperature, both storing methods of IJs had no effect on the mortality rate of G. mellonella larvae during the first two weeks of storing period. However, both storing methods and isolates affected the IJs during longer storing periods. Longer shelf-life could be improved in refrigerated containers than at room temperature. The results suggest that storing in calcium alginate granules was more suitable for storage of large quantities of nematode for commercial use in biological control programs. [ABSTRACT FROM AUTHOR]