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1.
A survey of two-year studies (2001-2003) was carried out in two olive groves sited at two representative olive growing areas, namely Paradise Park (arid area) and Burg E1-Arab farm (semi-arid area) to monitor the frequency of endemic Trichogramma species on olive moth (Prays oleae) and jasmine moth (Palpita unionalis). The suspended host bait traps were found to be a more practical and effective tool for collecting Trichogramma wasps than the attached ones. Four naturally occurring Trichogramma species were collected for the first time in Egypt from the olive groves, where releases have never been conducted. T.bourarachae was collected exclusively from Burg El-Arab farm. It seems that this wasp species adapts well to the semi-arid area. Three species, namely T. cordubensis, T. nr.pretiosum and T. cacociae were isolated from Paradise Park farm. All of these wasps were also bred from naturally parasitized host eggs during favorable and even at unfavorable temperature conditions of June-August. However, these endemic species did not occur naturally in sufficient numbers to keep the pest populations from reaching damaging levels.The excessive usage of insecticides and the oophagous predators (e.g., ants and lacewing larvae) are some factors that affect the performance of Trichogramma wasps in olive farms.The presence of warm weather wasp strains suggests the existence of well-adapted wasp species or swains which may be appropriate candidates for the control of target pests in olive groves. Additional study is required to determine the best “habitat-specific” species/strains of Trichogramma for augmentative release of naturally occurring wasps and to incorporate them into integrated pest management programs. Efforts should be made to conserve these endemic species from oophagous predators, hot weather and insecticides.The olive and jasmine moth-larvae and pupae found under tree canopies were bred and emerged parasitoids were listed.  相似文献   
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The Apteranthes europaea complex (Apocynaceae–Asclepiadoideae–Ceropegieae–Stapeliinae) distributed from Morocco/southern Spain along the North African coast of the Mediterranean Sea up to Sinai, Negev and southern Jordan is studied with emphasis on stem and flower morphology by SEM, chromosome sizes and flavonoid compounds. Apteranthes europaea was found to be rich in rather uncommon flavone glycosides. Of these, luteolin 4'-neohesperidoside represents the major flavonoid of all samples; luteolin-3'- O -(6'- O -sinapoylglucoside)-4'- O -neohesperidoside and luteolin-3'- O -(6'- O -feruloylglucoside)-4'- O -neohesperidoside are reported here for the first time. Flavonol glycosides also occur, but in much smaller quantities. The different flower morphs, variation in stem and corolla epidermal structures, slight variations in the length of the 2 n  = 22 chromosomes and in quantitative flavonoid composition are taxonomically best reflected by subdividing the complex into a western var. europaea (Europe and Africa) and an eastern var. judaica (Sinai, Arabia).  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 419–432.  相似文献   
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Light and temperature are two environmental factors that deeply affect bud outgrowth. However, little is known about their impact on the bud burst gradient along a stem and their interactions with the molecular mechanisms of bud burst control. We investigated this question in two acrotonic rose cultivars. We demonstrated that the darkening of distal buds or exposure to cold (5 °C) prior to transfer to mild temperatures (20 °C) both repress acrotony, allowing the burst of quiescent medial and proximal buds. We sequenced the strigolactone pathway MAX‐homologous genes in rose and studied their expression in buds and internodes along the stem. Only expressions of RwMAX1, RwMAX2 and RwMAX4 were detected. Darkening of the distal part of the shoot triggered a strong increase of RwMAX2 expression in darkened buds and bark‐phloem samples, whereas it suppressed the acropetal gradient of the expression of RwMAX1 observed in stems fully exposed to light. Cold treatment induced an acropetal gradient of expression of RwMAX1 in internodes and of RwMAX2 in buds along the stem. Our results suggest that the bud burst gradient along the stem cannot be explained by a gradient of expression of RwMAX genes but rather by their local level of expression at each individual position.  相似文献   
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An antibiotic resistant staphylococcus with bacteriophage pattern 52/42B/80/81* is frequently responsible for infectious outbreaks in the newborn nursery. Some time after an outbreak had occurred in the University of California's hospital nursery, family members of the infants were found to be infected with this strain. Two families were studied in detail. In one of them, infection developed in six of the seven members within eight months after the infant's arrival. In the other, half of the family members had recurrent infections during a 13-month period.Infants who left the nursery as asymptomatic carriers were found as likely to transmit the infectious strain as those with clinical infection. Considerable time sometimes elapsed before infection developed in either the infant or the family members. In one instance the first familial infection occurred six months after the infant had left the nursery as an asymptomatic carrier. Newborn infants are quite likely to disseminate antibiotic resistant staphylococci which they may acquire from a hospital nursery. Infections developing among persons in contact with a young infant must be treated with the possibility of a resistant hospital staphylococcus in mind.  相似文献   
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Sexually transmitted disease in a promiscuous insect, Adalia bipunctata   总被引:1,自引:0,他引:1  
Abstract.
  • 1 Sexually transmitted diseases (STDs) have rarely been reported in insects and other invertebrates. The majority of those reported involve organisms where sexual transmission is augmented by either vertical (i.e. inherited) transmission, or horizontal transmission, independent of host sexual activity.
  • 2 We here demonstrate the existence of an STD in the coccinellid beetle Adalia bipunctata. This species bears a parasitic mite of the genus Coccipolipus. We show that, like many other podapolipid mites, this mite is transmitted between host individuals at a high rate during copulation. It also appears to be transmitted at a low rate between non-copulating individuals.
  • 3 We show that infected female A.bipunctata produced eggs at a reduced rate, and that the eggs produced by infected females have highly decreased viability. However, no effect of infection upon host longevity was observed.
  • 4 The results are discussed in relation to the incidences of sexually transmitted disease in invertebrates in general, the causes of disease symptoms, and the importance of this disease in the evolution of A.bipunctata.
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The phenology of Fagus sylvatica was unaffected by exposure to an atmosphere of elevated CO2 (600 μL L-1) after two years of fumigation. Non-significant changes in nitrogen and phenolic content of the leaves decreased the nutritional status of beech for female larvae in elevated CO2 such that they responded by eating in a compensatory manner; males were unaffected. Rates of development, mortality and adult biomass of Rhynchaenus fagi were no different from those in ambient CO2 concentrations (355 μL L -1). It is possible that, with the changes in leaf chemistry affecting the females, fecundity will be altered, with important consequences for populations of beech weevil.  相似文献   
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