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Focuses on the extraction of vibronic bands of the compound SO2 by excitation and measured in a supersonic jet. Classification of five bands obtained based on Franck-Condon patterns; Utilization of a bandwidth dye laser to obtain the bands; Application of the technique coincides with the multilevel vibronic coupling model.

The objective of this study is to investigate the effect of different time and rates of boron (B) foliar application on olive (Olea europaea L.) tree's tissue boron concentration, total phenol, chlorophyll, total soluble sugars, and endogenous hormones. A field experiment was conducted during two successive seasons 2010/2011 and 2011/2012 using 20 years old olive trees cv. Frantoio. The trees are grown in sandy soil planted at 5 x 5 m apart under drip irrigation system at the Nuclear Research Center Experimental Farm, Inshas, El-Qaliubiya Governorate, Egypt. Boron was applied foliarly as boric acid at the following rates (0.0, 100, 200, 300, 400, 500 mg L-1) at flower initiation and after 1 and 2 months from flower initiation. Results showed that boron was significantly effective in increasing leaf, bud, and fruit boron concentration. Total phenol concentration in leaves and buds were significantly highest in the control treatment, significantly decreased as the boron application rate increased. Total chlorophyll, chlorophyll a and b, and total soluble sugars significantly increased as the boron application rate increased and the highest increase was achieved at 200 mg L-1 boron concentration rate. Leaf and bud endogenous indole acetic acid (IAA) and abscisic acid (ABA) were highest in the control treatment; they decreased as the boron application rate increased. However, gibberellic acid (GA3) increased in response to boron treatments compared with the control. The maximum increase was observed at 200 mg L-1 boron rate. We concluded that boron is mobile in olive tree as reproductive organs accumulated more boron than vegetative organs. There is evidence that boron is involved in reduction of phenols, increase in fruit set, and in sugar transport. A balance in endogenous hormones (IAA, GA, ABA) concentrations in olive tree has induced the maximum fruit set and yield. [ABSTRACT FROM AUTHOR]

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 leopard moth, Zeuzera pyrina (L.) (Lepidoptera: Cossidae), is a xylophagous species that has become a serious pest in the olive (Olea spp.) orchards in Egypt. Both chemical and biological control have scored poorly against this pest and additional methods are needed. A simple, but efficient UV-light-pheromone sticky trap ("Hegazi model") was devised for leopard moth mass trapping. Activity of leopard moth and efficiency of pheromone-baited, light, and pheromone and light traps were evaluated. The combination of light and sex pheromone was optimally attractive to leopard moth populations in olive orchards. A comparison between light traps baited with sex pheromone in mass-trapping method and conventional controls (insecticidal and physical removal of larvae) in heavily infested plots was carried out between 2002 and 2005. Leopard moths have long flight period, starting in mid-May and lasting until early November. Females of leopard moths were rarely trapped, but all had eggs. In mass-trapping plot, the seasonal captures and active galleries diminished from one year to the next, which may indicate the effectiveness of the method. From May 2003 to October 2005 greater reduction in total counts of active galleries was observed in mass-trapping plot compared with those recorded in the control field, in which chemical sprays and manual killing were performed. Yield from trees in mass-trapping field was significantly increased in comparison to control trees. The study strongly recommends the use of mass-trapping method instead of pesticides against the leopard moths, not only to control them but also to mass trap and monitor other lepidopterous pests of olive trees. [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]

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]

Earlier research has shown that the koinobiont parasitoid, Microplitis rufiventris, attacks and can develop on early instars of Spodoptera littoralis larvae with preference to third instars. However, the present study was carried out using the newly moulted sixth instar larvae at two different temperatures (20 ± 1 and 27 ± 1°C) to study the developmental interaction between the parasitoid and the last instar host larvae. Parasitoid eggs laid in singly parasitized host larvae invariably died. As the number of parasitoid eggs/host larvae increased, the proportion of eggs that hatched and number of viable parasitoid larvae successfully reached to their final instar increased. The effect of superparasitization seems to be dose (no. of eggs + parasitoid factors)-temperature-dependent. The results demonstrate a kind of‘Allee effect’ suggesting that superparasitized last instar S. littoralis larvae provide a better host environment than singly parasitized hosts for the parasitoid, M. rufiventris. This may be due to host's hormone and/or low dose of factors injected with parasitoid eggs. The supernumerary individuals of wasp larvae developed normally to the point of emergence but most did not successfully emerge from the host. The improvement of both hatchability and post-embryonic development of parasitoid wasp was significantly (P < 0.01) greater at 20°C than at 27°C. The results of the present study are useful in understanding the evolution of life-history strategies and host range in parasitic hymenoptera. [ABSTRACT FROM AUTHOR]

The solitary endoparasitoid,Microplitis rufiventris, attacks and can develop in earlier instars ofSpodoptera littoralislarvae with preference to third-instar larvae. We used the last stadium (sixth instar), a stage which is not naturally parasitized. The newly moulted larvae (0–3 h old) of this stadium were more acceptable for parasitization by the wasp females than the older ones (24 h old). Parasitization byM. rufiventriswasp of last instarS. littoralislarvae leads to dose (no. of eggs + parasitoid factors)-dependent effects which were more pronounced at 20°C than at 27°C. A single oviposition into a sixth instar host larva resulted in normal development of the host. However, superparasitization increased the proportions of developmentally arrested hosts and number of live wasp larvae. Development of supernumerary individuals of the parasitoid in the host larva leads to dose-related adverse effects on host growth and development. The present study may provide interesting opportunities for studying the physiological bases of host–parasitoid interactions and parasitoid intra-specific competition in the biological system considered. [ABSTRACT FROM AUTHOR]

A method for measuring the refractive index of low-transparent crude oils using a capillary tube interferometer is described. The method is based on analyzing the resulting transverse interference fringe patterns in terms of their positions with respect to the lens/capillary tube interferometer. The refractive indices of seven blended crude oils of low transparency were measured with accuracy of up to six decimal digits and were related to the API gravity of the oils. The ray tracing inside the capillary tube is explained and the transverse bell-shaped interference fringes are interpreted. [Copyright &y& Elsevier]

Time-resolved fluorescence (TRF) spectra of six crude oils from the eastern province of Saudi Arabia were excited using a pulsed laser radiation at 250 nm and measured at specific time gates (TG) within the leading and trailing edges of the laser temporal pulse. The spectra showed the presence of a shoulder near 380 nm that systematically decreased in intensity from high-grade to low-grade crudes, and also from earlier to later TGs. The intensities of these shoulders are shown to be useful in estimating the grades of crude oils, particularly when the TRF spectra are measured at TGs within the leading edge of the laser temporal pulse. Contour diagrams depicting the shapes of the TRF spectra as function of TG (within the leading and trailing edges) are also presented to serve as true fingerprints of the crudes. [Copyright &y& Elsevier]

The effect of temporary host deprivation on parasitization rates of Trichogramma cacoeciae Marchal and T. dendrolimi Matsumura was investigated. The study was conducted with females that we allowed to engage in 3 days of oviposition after various periods of host deprivation. It seems that the production and management of eggs by the two species is completely different. During the first day of oviposition, parasitization by T. cacoeciae was almost unaffected after 1 to 5 days of host deprivation. As deprivation time increased, however, the number of parasitized hosts decreased from an average of 28.6 ± 2.0 hosts provided at emergence to an average of 12.5 ± 2.3 hosts when the waiting time was 10 days. The number of hosts parasitized on the first day of parasitization by T. dendrolimi were not affected whatever the waiting test period. During the second or third days of oviposition, the lack of suitable hosts for T. cacoeciae did not depress egg-laying potentiality, whereas a strong reduction in parasitization rates by T. dendrolimi occurred in the next 2 days of oviposition whatever was the waiting period. This leads to ca. 50% reduction in total activity of 3 days of oviposition. Only in T. cacoeciae was it possible to distinguish between ageing and host deprivation. The data suggest that T. dendrolimi is a typical proovigenic species, while T. cacoeciae is neither definitely proovigenic nor synovigenic. A slight decrease in rate of emergence of offspring of T. cacoeciae females that had waited 8 to 10 days for their hosts was observed. As far as biological control is concerned, the efficiency of T. dendrolimi females may be more sensitive to host deprivation than T. cacoeciae. [ABSTRACT FROM AUTHOR]

The influence of sublethal dietary levels (0.4 p.p.m.) of a chitin synthesis inhibitor lefenuron {N-[2,5dichloro-4-(1,1,2,3,3,3,-hexafluoropropoxy)-phenylaminocarbonyl]-2 ,6-difluorobenzamide} on the development of Microplitis rufiventris teratocytes was investigated. Observations and data were taken on maturing teratocytes, i.e. at the end of parasitoid development. When embryogenesis of the parasitoid eggs was initiated in treated hosts, the dissociated cells of the embryonic membrane of some of the parasitoid larvae did not liberate in the haemolymph of the host, whereas in the other hosts, the released ones as individual cells scored the largest mean number per host larva. When young teratocytes were exposed to the treatment they were found in some cases clumping in masses or clustered around the parasitoid larvae. In treated hosts, different size classes of teratocytes co-existed. Larger and morphological abnormal cells were more common in hosts which contained older teratocytes at the time of treatments. Abnormal teratocytes were associated with developmental abnormalities of parasitoid larvae, possibly due to deterioration of the host environment. This observation was common in treated hosts and in few cases of untreated ones. A significant decrease in teratocyte size occurred 24 h after parasitoid emergence. Observations and results obtained in the present work suggested that: (1) teratocyte may function in controlling the growth and successful development of parasitoid larvae; (2) they might have a protective function through sequestering abnormal materials issuing in the haemolymph of the host either during the course of parasitoid development or due to external stress; and (3) number of teratocyte cells liberated from the embryonic membrane of parasitoid egg is not constant. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated whether application of Precocene II, an insect antiallototropin, to parasitized Spodoptera littoralis larvae can influence their total counts and differential haemocyte counts. Methodology of the study; Results and discussion on the study.

Presents information on a study which examined mature teratocytes in the body cavity of Spodoptera littoralis that was attacked by Microplitis rufiventris Kok. wasp. Methodology; Results and discussion.

Single vibronic level fluorescence spectra of bands in the 31120-32 160 cm- region of SO were measured under low rotational temperature conditions in an expanded supersonic jet. Eight weak bands were confirmed as belonging to the S O system : their resonance vibrational transitions were found to match the term energies of this isotope. The correlating bands in the S O system were identified by noting that the Franck-Condon patterns of their dispersed fluorescence spectra were similar to those of the S O bands. The analysis of the spectra also concludes that some of the weak bands in the above region can be due to S O ev e v bands whose upper levels have B B a vibronic symmetry. [ABSTRACT FROM AUTHOR]

The spectral region of the F band of SO2 was investigated in crossed supersonic jet and laser beams under conditions of low rotational temperatures. Eight major vibronic bands were identified within the region and their fluorescence spectra were selectively excited and measured. In each spectrum, the relative intensities of the vibrational resonance transitions, particularly for the (n,0,0) progressions, were found to change considerably when measured after different time delays following the exciting laser pulse. This indicated efficient collision-induced relaxation processes among the upper vibronic levels, which accounted for the unusual very strong transition into the (1,0,0) level. The non-resonance background fluorescence spectrum, which becomes present at the high rovibronic temperatures, was also investigated and discussed in the light of our findings. [ABSTRACT FROM AUTHOR]

Focuses on a study which examined the effects of superparasitism on the size and number of teratocytes found in the host Spodoptera littoralis at the completion of development of the solitary endoparasitoid Microplitis rufiventris. Major functions of teratocytes; Materials and methods; Results and discussion.

Provides information on a study which examined the effect of Precocene II, an anti-juvenile hormone, to the different development ages of Microplitis rufiventris Kok. teratocytes. Information on Microplitis rufiventris Kok; Materials and methods used in the study; Results and discussion.

Precocenes I & II (PI & PII) and juvenile hormone I (JHI) were topically tested on unparasitized and Microplitis rufiventris parasitized Spodoptera littoralis larvae. Parasitism interferes with normal host response to these compounds, decreasing their effectiveness. In all cases, the effect was dose-dependent. In contrast to PII or JHI, the lower dose of PI was more effective than the higher one. Application of JHI to S. littoralis larvae was less harmful to parasitoid development than either PI or PII. It is therefore emphasized that the commercial utilization of insect growth regulators should be undertaken carefully to minimize possible disruptive effects on developing parasitoids. [ABSTRACT FROM AUTHOR]

Studies the relative mixing coefficients of zero-order [sup 1]B[sub 1](n,0,0) levels in the [sup 1]B[sub 1]-A[sub 2] hybrid wave functions of the vibronic bands of SO[sub 2] in the 32184-34040 cm[sup -1] region. Dispersed fluorescence spectrum of the vibronic band.

The effect of mating status and age of the female of Microplitis rufiventris parasitoid on the growth pattern of its teratocytes during the larval development is described as well as the changes in the number of these cells. The growth pattern of teratocytes derived from haploid eggs significantly differed from that of eggs deposited by mated females. Both cell diameter and the number of maturing M. rufiventris teratocytes was fertilization-dependent. Following the parasitization of Spodoptera littoralis larvae with virgin parasitoid females, the host larvae hosted a large number of cells of smaller size at the end of parasitoid development. The opposite effect was seen when the host larvae contained female parasitoid larvae. The age of the female at parasitization had an effect on the maximum cell size attained prior to parasitoid emergence. It seems that there are two factors other than mating which affect the number of teratocytes: degeneration inside the host haemolymph and to some degree accidental ingestion by parasitoid larva. [ABSTRACT FROM AUTHOR]

1 IntroductionMicroplitis rufiventris Kok. (Hym., Braconidae) is an internal solitary parasitoid of many noctuid caterpillars including the cotton leafworm Spodoptera littoralis (Boisd.) (Kokujev 1914; Hammad et al. 1965; Gerling 1969), the lesser cotton worm S. exigua Hbn. (Meier 1929; Thompson 1946; El-Minshawy 1963); S. latebrosa Lederer (Hammad et al. 1965) and American bollworm Heliothis armigera Hbn. (Meier 1929; Ibrahim & Tawfik 1975). When the egg of M. rufiventris hatches in its host, S. littoralis, spherical cells from the serosa that envelope the parasitoid embryo are released into the host’s haemolymph. Approximately 400 cells are liberated from an egg of the parasitoid. These cells increase in size, reaching a maximum average diameter of 137 μm at the completion of parasitoid development (Khafagi 1997). These cells are most frequently called ‘teratocytes’ (— 1968, 1971; Vinson 1970). It is reported that the presence of large numbers of the teratocytes is indicative of superparasitism but their number does not give an indication to the exact number of parasitoid eggs from which the cells have been derived (—, — Khafagi et al. 1998). Therefore, it was of interest to initiate prediction studies on egg and teratocyte numbers in superparasitized host larvae. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study about the effects of sugar malabsorption of the effectiveness of standard glucose-based and reduced-osmolarity maltodextrin (MD)-based oral rehydration solutions (ORS). Boys with noncholera diarrhea and moderate dehydration were randomly assigned to either standard ORS or MD-ORS. Children given with standard ORS develop osmotic diarrhea due to the combined effect of transient sugar malabsorption and slight hypertonicity of the ORS. Reduced-osmolarity glucose-based ORS is found to be superior to both standard and reduced-osmolarity solutions.