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The leaf miners, Liriomyza trifolii (Burgess) and L. bryoniae (Kaltenbch), (Diptera: Agromyzidae) are of the major pests that attack faba bean (Vicia faba) in Egypt. The incidence of diapause in larval-pupal parasitoids of these pests was studied by large-scale field samplings of their mature larvae and puparia, which were reared under natural outdoor conditions. The population size of L. trifolii was greater than those of L.bryoniae. Four larval-pupal parasitoids; Pseudopzomachus masii Nixon and Opius basalis Fischer (Braconidae), Halticoptera circulus (Walker) and Halticoptera sp. (Eulophidae) were recorded from the puparia of both leaf miner species between 2012 - 2015 seasons. P. masii was the most predominant parasitoid species in the seasons of study. The onset of pupal diapause was found among paper of the 1st sample, during the favorable weather conditions in the host insect until last collected samples 2 weeks before harvest. So, the diapause in Liriomyza spp. seems to be genetically programmed. Two types of diapause were observed during the season: firstly, a facultative winter diapause of 7-8 months, and secondly, a longer winter diapause of 11-21 months. The diapause intensity was highly variable depended upon the time in the season and the Liriomyza species. It appears that the diapaused wasps were able to maintain close developmental synchrony with the proportion of non-parasitized host puparia. This is the first report of diapause in Liriomyza spp. attacking faba bean plants and their larval-pupal parasitoids from the northern region of Egypt. [ABSTRACT FROM AUTHOR]

Egg laying capacity, sex ratio and adult longevity of males and females of the parasitoid species Bracon hebetor (Say) (Hymenoptera: Braconidae) were studied by exposing the wasps to different larval density of the greater wax moth, Galleria mellonella (L.) (Lepidoptera: Pyralidae). Females of B. hebetor could regulate allocation of eggs among host larvae by decreasing the number of eggs laid on a host as host density increases. Also, the wasp females seemed to regulate sex ratio (male /total) based on the number of eggs on the hosts and number of host larvae they encountered. Survival of B. hebetor adults was significantly different among wasps provided with different types of food. Wasp females lived longer period than males when kept only with wax moth larvae. The wasps laid lower number of eggs than those provided with hosts and honey. Combined use of G. mellonella larvae and honey had significant increase on reproductive capacity and longevity of B. hebetor wasps. [ABSTRACT FROM AUTHOR]

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]

The first application of a recently established method of intensity-normalized time-resolved fluorescence (TRF) techniques in the identification of crude petroleum oils in remote sensing is introduced. The excitation wavelength was that of a pulsed Nd:YAG laser at λ = 355nm, and the resulting TRF spectra, measured at specific time-gates, were used to construct fingerprints that reflect only the shapes of the TRF spectra. The method is found to be sensitive enough to discriminate between crude oils of different grades in remote sensing even though the 355nm wavelength is not the optimum wavelength for fluorescence excitation of crude oil. Fingerprints of four crude oils of different grades have been constructed using TRF spectra measured at 5ns time-gate widths and a trend in the fingerprints relating to the crude oils' grades has been found and described. [ABSTRACT FROM AUTHOR]

Different developmental stages of Microplitis rufiventris Kok. larvae were each exposed to a sublethal dosage (0.4 ppm) of Lefenuron [N-{2,5-dichloro-4-(1,1,2,3,3,3-hexafluoropropoxy)-phenylaminocarbonyl}-2, 6-difluorobenzamide] or Lefenuron/Deltanet [O-n-butylO-(2.2-dimethyl-2, 3-dihydrobenzofuran-7-y1)-N, N'-dimethyl-N-N'-thiodicarbamate] by feeding treated artificial diets to parasitized Spodoptera littoralis (Boisd.) larvae to evaluate their effects on the reproductive potential of resulting parasitoids. Lefenuron treatments caused a great reduction in the reproductive ability of either the host insect or its parasitoid. Ovaries of parasitoid females (1 day old) emerged from Lefenuron/Deltanet treatments contained more ova than those from either Lefenuron or controls. Experienced females from Lefenuron/Deltanet treatments deposited significantly more eggs and contained at death more remaining mature oocytes in their calyx and egg-reservoirs. The combination of carbamate insecticide (Deltanet) and chitin-inhibiting growth regulator (Lefenuron) may enhance the reproductive ability of insect parasitoid and may provide a potential means for developing more effective biological control methods against insect pests. [ABSTRACT FROM AUTHOR]

The fluorescence excitation spectrum of SO in the 32 200-33 300 cm energy region was recorded, at very low rotational temperature, in a pulsed supersonic jet. The band centres and relative intensities of about 60 well-resolved vibronic bands were determined in this region, which extends the previously available data by 800 cm. Single vibronic level fluorescence spectra of two neighbouring vibronic bands in the D-band region along with a few filtered excitation spectra are also presented as an example of the resolution for the listed bands. [ABSTRACT FROM AUTHOR]