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1.
Somatic embryogenesis and plantlet formation were obtained from 60–75 day old cell cultures of carnation. Callus was generated on MS basal medium supplemented with 2,4-dichchlorophenoxy acetic acid (2,4-D). Removal of 2,4-D during subsequent subculturing of cell suspensions resulted in formation of embroids. These somatic embryos originated from single cells and their early development proceeded normally with clearly defined apical and root meristems. Some embryos developed into plants and were acclimatized to ex vitro conditions.  相似文献   
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In a competitive sympatric association, coexisting species may try to reduce interspecific interactions as well as competition for similar resources by several ecological and behavioral practices. We studied resource utilization of three sympatric primate species namely, lion-tailed macaques (Macaca silenus), bonnet macaques (M. radiata) and Hanuman langurs (Semnopithecus entellus) in a tropical rainforest of the central Western Ghats, south India. We studied resource use, tree-height use, foraging height, substrate use when consuming animal prey and interspecific interactions. The results revealed that across the year, there was very limited niche overlap in diet between each species-pair. Each primate species largely depended on different plant species or different plant parts and phenophases from shared plant species. Primate species used different heights for foraging, and the two macaque species searched different substrates when foraging on animal prey. We also recorded season-wise resource abundance for the resources shared by these three primate species. While there was low dietary overlap during the dry season (a period of relatively low resource abundance), there was high dietary overlap between the two macaque species during the wet season (a period of high resource abundance for the shared resources). We observed only a few interspecific interactions. None of these were agonistic, even during the period of high niche overlap. This suggests that the sympatric primate species in this region are characterized by little or no contest competition. Unlike in some other regions of the Western Ghats, the lack of interspecific feeding competition appears to allow these primates, especially the macaques, to remain sympatric year-round.  相似文献   
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We assessed the distribution and conservation status of bonnet macaques (Macaca radiata), rhesus macaques (Macaca mulatta) and Hanuman langurs (Semnopithecus entellus) in the state of Karnataka, India. Karnataka is situated in southwest India with an area of 191,791 km2. A total of 9697 km of vehicular survey was made from November 2001 to July 2004. We also visited 107 temples/tourist spots to determine the presence of primates. Bonnet macaques and Hanuman langurs were widely distributed, whereas rhesus macaques were not found in the state. However, bonnet macaques were absent in a few districts in the northern plains and Hanuman langurs were absent in some districts of the southern plains. A total of 205 groups of bonnet macaques and 139 groups of Hanuman langurs were sighted. The relative encounter rate of both species differed across biogeographic zones. Bonnet macaques were largely encountered in the Western Ghats and the Southern Plateau whereas Hanuman langurs were abundant in the Western Ghats and Northern Plains. We found that bonnet macaques have been eliminated from about 48% temples/tourist spots where they occurred in the recent past. The Hanuman langur population of Dharwar–Haliyal Road was assessed during April 2003, and we found that the present population size was about 38% of a previous survey in 1961. Habitat change, hunting/trapping and translocation were the major factors causing a decline in the langur population.  相似文献   
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International Journal of Primatology - Species conservation depends on the needs of the species concerned. For example, obligatory forest-dwelling and typically urban primate species require...  相似文献   
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Resource partitioning in a community of diurnal arboreal mammalsconsisting of the lion-tailed macaque Macaca silenus, bonnetmacaque (BM) Macaca radiata, Nilgiri langur Semnopithecus johnii,and the Indian giant squirrel Ratufa indica of the Western Ghats,southern India, was studied. Differences in their diet, verticalstratification, food resource niche breadth, niche overlap,and behavioral interactions were examined. Resource partitioningwas through differential habitat use, resource use, and verticalstratification. Of the four species, the BM was not a residentspecies and made frequent forays into evergreen forest fromthe adjacent deciduous forest during the flowering season ofCullenia exarillata and fruiting season of Ficus microcarpa.The macaques had narrower niches, and the langur and the squirrelhad wider niches. Niche overlap was highest between the twomacaques. Overlap among the study species was particularly pronouncedduring the flowering of C. exarillata. There was significantcorrelation between niche overlap and intolerance among thestudy species. Certain species pairs showed little or no mutualintolerance despite high overlap. Cooperative interactions suchas alarm calls occurred more frequently among the resident species.Interaction matrices revealed an underlying pattern of interspecificdominance hierarchy, with the BM dominating over the other threespecies. Our study suggests that the BM do not coexist withthe other three because of high overlap with its congener andlow occurrence of cooperative interactions.  相似文献   
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A practical approach to understanding lateral asymmetries in body, brain, and cognition would be to examine the performance advantages/disadvantages associated with the corresponding functions and behavior. In the present study, we examined whether the division of labor in hand usage, marked by the preferential usage of the two hands across manual operations requiring maneuvering in three-dimensional space (e.g., reaching for food, grooming, and hitting an opponent) and those requiring physical strength (e.g., climbing), is associated with higher hand performance in free-ranging bonnet macaques, Macaca radiata. We determined the extent to which the macaques exhibit laterality in hand usage in an experimental unimanual and a bimanual food-reaching task, and the extent to which manual laterality is associated with hand performance in an experimental hand-performance-differentiation task. We observed negative relationships between (a) the latency in food extraction by the preferred hand in the hand-performance-differentiation task (wherein, lower latency implies higher performance), the preferred hand determined using the bimanual food-reaching task, and the normalized difference between the performance of the two hands, and (b) the normalized difference between the performance of the two hands and the absolute difference between the laterality in hand usage in the unimanual and the bimanual food-reaching tasks (wherein, lesser difference implies higher manual specialization). Collectively, these observations demonstrate that the division of labor between the two hands is associated with higher hand performance.  相似文献   
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We carried out a survey on roadside dark-bellied bonnet macaques (Macaca radiata radiata) on the highways around the south Indian city of Mysore. The present survey was the fourth since 1989 on the same populations. We divided the habitats into intensive cultivation (IC), wet cultivation (WC), and scrub forests (SC). The number of groups has significantly reduced from 54 to 31 and the number of animals has declined from 1,207 to 697 from 1989 to 2009. This decline has been recorded only in the IC and WC areas, whereas the population in SC with places of Hindu worship has remained stable. Due to the loss of roadside Ficus trees over the years, the habitat of the monkeys has almost disappeared. Since bonnet macaque is not primarily a forest-dwelling species, the seemingly widespread primate may soon become ‘threatened’ if the non-forest populations continue to decline. Scrub forests in small hillocks housing Hindu temples remain the only prospective places for conservation of bonnet macaques.  相似文献   
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