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ABSTRACT In a study of predation on ground-nesting birds at South San Francisco Bay (South Bay), California, USA, we analyzed stomach contents and stable isotopes of carbon and nitrogen to identify commonly consumed prey. We obtained the stomach contents from 206 nonnative red foxes (Vulpes vulpes regalis) collected in the South Bay area and Monterey County during 1995–2001 and from 68 feral cats (Felis silvestris) from the South Bay area during 2001–2002. We determined prey identity, biomass, and frequency, described seasonal diet trends, and derived an Index of Relative Importance. Avian species were the most frequent prey we found in the stomachs of red foxes from South Bay (61%), whereas small rodents were most frequent for red foxes from Monterey County (62%). Small rodents were the most frequent prey we found in feral cats (63%). Carbon and nitrogen isotopic signatures for foxes supported stomach content findings. However, isotope results indicated that cats received a majority of their energy from a source other than rodents and outside the natural system, which differed from the stomach content analysis. We demonstrated the utility of both stable isotope and stomach content analyses to establish a more complete understanding of predators' diets. This information aids natural resource managers in planning and evaluating future predator-removal programs and increases our understanding of the impacts of nonnative foxes and cats on native species.  相似文献   
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In investigation was conducted annually from 2002 to 2005 between the second week of May and the end of September on the incidence of scarab beetle, Schizonycha ruficollis (Fabricius) in a teak (Tectona grandis L.f.) nursery at Ramdongari, Nagpur, India. The immature stages, that is white grubs of the scarab beetle damaged 14%-52% of teak seedlings in the nursery beds, whereas the adult of the species, that is scarab beetles, were recorded on three new host trees ( Ziziphus xylopyra, Acacia catechu and A. leucophloea) in addition to the reported hosts such as ziziphus (Z. jujuba and Z. mauritiana). Beetles of the S. ruficollis started emerging from the nursery beds just after the pre-monsoon showers and continued for 10-18 days. While beetle of S. ruficollis defoliated tree hosts available in the surroundings, the immature stages of the beetle caused major damage by feeding on root systerfls of teak seedlings with symptoms of wilting and mortality in forest nursery beds. The result of chemical and biological treatments for the management of grubs of S. ruficollis in nursery beds indicated phorate 10% granular at the rate of 20 g/m^2 and chlorpyriphos 20% emulsifiable concentrate at the rate of 5.0 mL/m^2 to be effective. Grubs of S. ruficollis have not been recorded previously as a major pest of teak (T. grandis). This is also the first report on occurrence of S. ruficollis adults on tree hosts such as Z. xylopyra, A. catechu and A. leucophloea. White grubs being pests of economic importance and the toughest insects to manage, information given in this paper on incidence, pest status and management of Schizonycha ruficollis is of importance to researchers and forest nursery managers.  相似文献   
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Studies on the initiation of adventitious roots on mung bean hypocotyl   总被引:2,自引:0,他引:2  
During the early stages of root induction in hypocotyls of mungbean cuttings, four new peroxidase isoenzymes are formed inthat part of the cutting that produces roots. These isoenzymesare in addition to and different from the three already presentin the hypocotyl. Forty-eight hr is required for the changeto take place from the original three to seven isoenzymes. Thechange in isoenzyme pattern and root initiation itself are retardedwhen streptomycin is applied during the very early stages ofroot induction. However, during the latter part of the first24-hr period after the cutting is made and when some of thenew isoenzymes have already been formed, the rooting processbecomes insensitive to this antibiotic. Cytologically, the occurrenceof cell division is paralleled by the formation of the fournew peroxidase isoenzymes. The delay in the occurrence of celldivision caused by the presence of streptomycin is paralleledby a similar delay in the formation of the four new isoenzymes. (Received November 27, 1970; )  相似文献   
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Epidemiological studies of Colletotrichum gloeosporioides disease of cocoa   总被引:2,自引:0,他引:2  
The intensities of foliar infection (leaf blight and shot hole) and pod rot, caused by Colletotrichum gloeosporioides, were recorded from a cocoa-areca mixed garden and a cocoa-monocrop garden during 2 years. The intensity of pod rot was recorded from both the gardens. The intensities of leaf blight and shot hole gradually increased from July, reached a peak during September-November, decreased thereafter and reached the lowest level during April-June. Increase in leaf infection was associated in both plantings and in both years with the period of rain (June-November). The phylloplane population of C. gloeosporioides also increased during June-November when the temperature tended to be low and constant with high rainfall and relative humidity. During this period there were few susceptible stages of pods (cherelles and young pods) and pod infection was very low. Nearly mature pods were free from infection. I n both years, pod infection was more in the cocoaareca mixed garden than' in the cocoa-monocrop; it was observed during January-May, when the susceptible stages were mostly prevalent but when the C. gloeosporioides population was low and the climatic factors appeared to be relatively unfavourable. This may be one reason for the lesser incidence of pod rot when compared to foliar disease.  相似文献   
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The Asian endemic dobsonfly genus Nevromus Rambur is revised. Six species of Nevromus are described or re‐described, and illustrated. Nevromus aspoeck Liu, Hayashi & Yang sp.n. , Nevromus austroindicus Liu & Viraktamath sp.n. and Nevromus gloriosoi Liu, Hayashi & Yang sp.n. are described from southernmost Yunnan of China and northern Thailand, southern India, and Borneo, respectively. A new combination Nevromus intimus (McLachlan) comb.n. is also identified. An interspecific phylogeny of Nevromus is reconstructed based on the adult morphological data, resulting in identification/recognition of two main clades, i.e. the mainland clade and the insular clade. Combining this phylogeny and the updated geographical distribution, an Indian origin and a historically widespread distribution in southern Eurasia is proposed for Nevromus. The deep divergence between the mainland and insular clades within Nevromus might have happened during the separation of Sundaland from Eurasia. The Tertiary orogenic events after the collision between the Indian subcontinent and Eurasia probably affected the speciation within the mainland clade of Nevromus, whereas the island formation of Borneo, Java and Sumatra shaped the fauna within the insular clade of this genus. The biogeographical pattern of Nevromus revealed in this study appears to have more general significance for understanding the faunal origin and diversification of the habitat‐specific or poorly dispersing insects from the Oriental realm.  相似文献   
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This guidance details the needs of children, and the qualities of parenting that meet those needs. Parental mental disorders can damage the foetus during pregnancy through the action of drugs, prescribed or abused. Pregnancy and the puerperium can exacerbate or initiate mental illness in susceptible women. After their birth, the children may suffer from the social disadvantage associated with severe mental illness. The parents (depending on the disorder, its severity and its persistence) may have intermittent or prolonged difficulties with parenting, which may sometimes result in childhood psychological disturbance or child maltreatment. This guidance considers ways of preventing, minimizing and remedying these effects. Our recommendations include: education of psychiatrists and related professions about the effect of parental mental illness on children; revision of psychiatric training to increase awareness of patients as caregivers, and to incorporate relevant assessment and intervention into their treatment and rehabilitation; the optimum use of pharmacological treatment during pregnancy; pre-birth planning when women with severe mental illness become pregnant; development of specialist services for pregnant and puerperal women, with assessment of their efficacy; community support for parenting by mothers and fathers with severe mental disorders; standards of good practice for the management of child maltreatment when parents suffer from mental illness; the importance of multi-disciplinary teamwork when helping these families, supporting their children and ensuring child protection; the development of child and adolescent mental health services worldwide.  相似文献   
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Selection of high yielding genotypes to be carried over to subsequent selection cycles in a breeding programme can sometimes be accomplished using a suitable index of secondary traits that may be relatively less sensitive to genotype‐by‐environment interactions than yield. We used the concept of correlated response to selection to measure the relative efficiency of nine selection indices. The results showed that the selection index, based on median and semi inter‐quartile range, which was actually used in identifying high yielding genotypes, had an efficiency that is comparable to the best index, the latter being a modification of the Elston index.  相似文献   
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