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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 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]

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]

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 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.

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]

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.