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61.
Nymphal development of the predator Macrolophus pygmaeus Rambur (Hemiptera: Miridae) was investigated on two eggplant varieties, Bonica and Black Beauty, in an attempt to identify the possible role that plant variety plays in the development and survival of the predator and to determine whether these biological characteristics are influenced by temperature and prey. The development of nymphs was studied in the presence and absence of the prey, Myzus persicae (Sulzer), at 15, 20, 25, 30, and 35°C, 65 ± 5% RH, and 16:8 h (L:D) photoperiod. Significant differences in the periods of nymphal development were evident in the two varieties at 15°C when M. persicae was offered as prey, and at 15 and 30°C, when there was no prey, significantly shorter periods of development were recorded on Bonica than on Black Beauty. Mortality rates of the nymphs were similar in the presence of prey on both varieties but, in the absence of prey, higher mortality rates were recorded on Black Beauty than on Bonica. In both presence and absence of prey, at 35°C, a small number of nymphs reached adulthood on Bonica, whereas no nymphs did so on Black Beauty. Therefore, the less suitable variety, Black Beauty, had a significant effect on the development and survival of nymphs of this predator, mainly in the absence of prey and at lower and higher temperatures. It is concluded that the selection of a suitable variety for the development and survival of M. pygmaeus, particularly in the absence of prey, could improve the efficiency of a biological control program in which this predator is going to be used. This is of particular importance for its establishment and effectiveness at the beginning of the growing season when temperature is relatively low and the prey is absent or scarce, as well as in summer when temperatures are high enough (around 30°C or even higher).  相似文献   
62.
The conversion of forest to agriculture continues to contribute to the loss and fragmentation of remaining orang‐utan habitat. There are still few published estimates of orang‐utan densities in these heavily modified agricultural areas to inform range‐wide population assessments and conservation strategies. In addition, little is known about what landscape features promote orang‐utan habitat use. Using indirect nest count methods, we implemented surveys and estimated population densities of the Northeast Bornean orang‐utan (Pongo pygmaeus morio) across the continuous logged forest and forest remnants in a recently salvage‐logged area and oil palm plantations in Sabah, Malaysian Borneo. We then assessed the influence of landscape features and forest structural metrics obtained from LiDAR data on estimates of orang‐utan density. Recent salvage logging appeared to have a little short‐term effect on orang‐utan density (2.35 ind/km 2), which remained similar to recovering logged forest nearby (2.32 ind/km 2). Orang‐utans were also present in remnant forest patches in oil palm plantations, but at significantly lower numbers (0.82 ind/km 2) than nearby logged forest and salvage‐logged areas. Densities were strongly influenced by variation in canopy height but were not associated with other potential covariates. Our findings suggest that orang‐utans currently exist, at least in the short‐term, within human‐modified landscapes, providing that remnant forest patches remain. We urge greater recognition of the role that these degraded habitats can have in supporting orang‐utan populations, and that future range‐wide analyses and conservation strategies better incorporate data from human‐modified landscapes.  相似文献   
63.
R Labonte J 《ZooKeys》2010,(56):207-218
In 2003, an Asian bark beetle, Scolytus schevyrewi Semenov (Coleoptera: Curculionidae: Scolytinae), the banded elm bark beetle, was detected for the first time in North America. This paper modifies the Wood (1982) key to the species of Scolytus Geoffroy to enable identification of Scolytus schevyrewi in North and Central America. Variation of diagnostic characters in Scolytus schevyrewi is discussed.  相似文献   
64.
A method is described for the culture of larvae of Scolytus multistriatus and Scolytus scolytus on an artificial medium following exposure to cultures of microorganisms. In control cultures, a natural mortality rate of 21.2% was found for S. multistriatus and 17.6% for S. scolytus. The effects of Trichoderma harzianum, T. polysporum and Scytalidium lignicola on fifth instar larvae of S. scolytus and S. multistriatus reared on the artificial medium were studied. The fungi were larvicidal and larval mortality was increased to more than 80% by inoculation of the larvae with the fungi. Another fungus, Phomopsis oblonga, had little effect on larvae of S. scolytus. The results are discussed in relation to mechanism of pathogenicity of the fungi and their potential use in the control of Dutch elm disease. It is proposed that with modifications, the method is applicable to other bark beetle pests.  相似文献   
65.
The medical problems of great apes including gorillas (Gorilla gorilla), orangutans (Pongo pymaeus), and chimpanzees (Pan sp.) published during the last decade are reviewed. Anesthetic techniques, diseases or organ systems, neoplasia, infectious diseases, and reproductive problems are reviewed. Gonadal tumors and atherosclerosis in great apes appear frequently in the literature. Diseases with suspected viral etiology include papillomas in chimpanzees, retrovirus-associated lymphomas in gorillas, and various herpesvirus disease. Technology developed for human medicine has expanded the diagnostic opportunities for clinicians working with great apes.  相似文献   
66.
The SSP program for orangutan (Pongo pygmaeus ssp.) was initiated in 1982. Since that time, the Propagation Group has dealt with issues related to improving captive management of the species. Prior to 1982, most orangutans in North America were managed as a single species, though a number of institutions did house their Bornean and Sumatran specimens separately. However, the determination of race at that time was made largely on the basis of physical appearance, a method subsequently proven imprecise. A major achievement of the SSP has been the refinement of orangutan subspecies determination; SSP-sponsored karotyping has determined, on a chromosomal level, the true subspecies of virtually every orangutan managed by the SSP. The validity of these results has been confirmed by recent fieldwork, also completed under the auspices of the SSP. Since 1985, as a result of these captive and field data, the SSP has held to the policy that subspecific hybrid orangutans should not be produced; to that end, there is a moratorium on the breeding of hybrid animals. Another significant step taken by the SSP group is the completion of the sophisticated demographic and genetic analyses, leading to the development of a Masterplan for this species and its captive management. Goals for the near future include refinement of the Masterplan analyses and publication of a new international studbook for the species.  相似文献   
67.
It is well known that the environment significantly influences the behavior of captive animals. However, the specific nature of the cues that promote speciestypical behavior patterns is not usually known. This study extends an earlier investigation by Wilson (Zoo Biology 1: 201–209, 1982). The objective was to identify and quantify specific environmental components that influence activity levels in orangutans. Six enclosure variables were quantified, and activity levels measured, for 29 orangutans housed in nine zoological parks. Multiple regression analysis indicated that the combination of the number of animals, amount of usable surface area, number of movable objects, and enclosure volume was the best predictor of activity levels, accounting for 58% of the variance in activity levels. It was concluded that the provision of large enclosures, containing large numbers of movable objects and providing social opportunities, would promote higher levels of activity in captive orangutans. © 1992 Wiley-Liss, Inc.  相似文献   
68.
Dental evolution of the orang-utan in China   总被引:1,自引:0,他引:1  
The main focus of this paper is to report the spatial and temporal distributions of fossil and subfossil orang-utans in south and southwest China from the late Miocene through Pliocene and Pleistocene. We will describe fossil samples and their odontometrics in order to estimate their body size through time. Furthermore we will also discuss their taxonomic status and evolutionary changes. Then, we will explore the possible reasons why and how these living fossils retreated to their present habitats.  相似文献   
69.
倭蜂猴的产热及细胞呼吸特征   总被引:5,自引:2,他引:3  
倭蜂猴的最大非颤抖性产热较低,但占调节性产热的比例。交高;褐色脂肪组织BAT)重量也较其他灵长类大,产热生也较强;肝脏线粒体氧化能力较低,与其具有较低的BMR和体温波动较大有关。倭蜂猴相对较低的MST和低水平的RMR对其凭许性和节约能量极为有利。  相似文献   
70.
Echolocation behaviour and the structure of calls of Pipistrellus pygmaeus and Pipistrellus pipistrellus were studied by using a time expansion bat detector. Echolocation signals were recorded in the field in south-eastern Moravia and northern Bohemia (Czech Republic) and in an ad hoc experimental laboratory. For each of the species, multivariate analysis of variance (MANOVA) indicated significant differences in calls produced inside the experimental room and in the open. Paired t -tests and MANOVA were also used to reveal influences of interindividual contacts in each of the cryptic species on the spectral patterns of call variables. Differences were found in the spectral variables of echolocation calls of an individual flying in the room alone and in a group of conspecifics. The possibility that bats use their flexibility to avoid mutual disturbances of echolocation calls was tested. We found that bats flying in a group modify the parameters of their echolocation signals according to the presence of other individuals of the same species. These differences can indicate jamming avoidance and recognition of own echoes. However, they did not change the parameters if individuals of another species were present. Social calls are more numerous when bats fly in a mixed-species group than in a monospecific group.  相似文献   
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