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1.
ITS1 sequence data was obtained for fireweed (Senecio madagascariensis) andS. lautus from Australia,S. madagascariensis andS. inaequidens from South Africa andS. madagascariensis from Madagascar. Despite the low level of variation (0.0–3.4%), these data further resolve the controversy concerning the identity and origin of fireweed. They confirm that fireweed is part of the South AfricanS. madagascariensis/S. inaequidens complex, and indicate that the infestation in Australia originated from South Africa as opposed to Madagascar. This will facilitate a resumption of biological control efforts in Australia and will direct surveys for control agents to South Africa.  相似文献   

2.
The Malagasy big‐headed turtle (Erymnochelys madagascariensis) is the only Erymnochelys species living in lakes, rivers and watersheds of western Madagascar. This species is endangered due to over harvesting of natural populations for human consumption. Eleven nuclear microsatellite loci were isolated from a genomic DNA library derived from a free‐ranging Malagasy big‐headed turtle from the Beroboka Classified Forest, Madagascar. Population genetic parameters were estimated on 10 individuals sampled from Ampijoroa and Andranohobaka River, Madagascar, to determine marker utility and as preliminary baseline values to study future populations in these locations.  相似文献   

3.
Twenty-two nuclear microsatellite loci were isolated from a genomic DNA library derived from Madagascar’s Rousettus madagascariensis. Marker characteristics were determined from a single population (37 individuals) from Fort Dauphin (southeastern Madagascar). Sixteen of the 22 loci were within Hardy–Weinberg expectations. These loci are highly informative with polymorphic information content values ranging between 0.757 and 0.916. These loci will provide valuable information for the study of population genetics and gene flow within this species of bats. Due to the dramatic reduction and alteration of their habitat, data generated utilizing this marker suite will potentially provide additional information for the effective long-term management of this near-threatened bat species.  相似文献   

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I describe distinctive feeding signs in living tree-bamboo (Ochlandra capitata) in two rain forest areas of Madagascar, for which aye-ayes (Daubentonia madagascariensis) are almost certainly responsible. Aye-ayes are present in both sites.  相似文献   

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Secusio extensa (Lepidoptera: Arctiidae) was evaluated as a potential biological control agent for Madagascar fireweed, Senecio madagascariensis (Asteraceae), which has invaded over 400 000 acres of rangeland in the Hawaiian Islands and is toxic to cattle and horses. The moth was introduced from southeastern Madagascar into containment facilities in Hawaii, and host specificity tests were conducted on 71 endemic and naturalized species (52 genera) in 12 tribes of Asteraceae and 17 species of non‐Asteraceae including six native shrubs and trees considered key components of Hawaiian ecosystems. No‐choice feeding tests indicated that plant species of the tribe Senecioneae were suitable hosts with first instars completing development to adult stage on S. madagascariensis (78.3%), Delairea odorata (66.1%), Senecio vulgaris (57.1%), Crassocephalum crepidioides (41.2%), and at significantly lower rates on Emilia fosbergii (1.8%) and Erechtites hieracifolia (1.3%). A low rate of complete larval development also was observed on sunflower, Helianthus annuus (11.6%), in the tribe Heliantheae. However, sunflower was rejected as a potential host in larval‐feeding and adult oviposition choice tests involving the primary host S. madagascariensis as control. Although larvae died as first instars on most test species, incomplete development and low levels of feeding were observed on nine species in the tribes Heliantheae, Cardueae and Lactuceae. Larvae did not feed on any non‐Asteraceae tested, including species with similar pyrrolizidene alkaloid chemistry, crops, and six ecologically prominent native species. Because all species of Senecioneae are non‐native and weedy in Hawaii, these results indicate that S. extensa is sufficiently host‐specific for introduction for biological control. High levels of feeding damage observed on potted plants indicate that S. extensa can severely impact the target fireweed as well as D. odorata, a noxious weed in native Hawaiian forests.  相似文献   

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Cryptostegia madagascariensis is a plant native from Madagascar, belonging to the Apocynaceae that is invading the native vegetation in Northeast Brazil and threatening the unique riverine formations dominated by the carnauba palm. Individuals of C. madagascariensis cultivated in the campus of the Universidade Federal de Viçosa, state of Minas Gerais, Brazil, showing leaf spot symptoms of unknown etiology were observed. Two fungal species were found associated to such leaf spots: Colletotrichum gloeosporioides and a new species of Pseudocercospora. The latter was named Pseudocercospora cryptostegiae-madagascariensis and described herein. The discovery of those two fungal pathogens on C. madagascariensis coincide with the recognition that the weedy vine that is involved in the infestations in the Northeast of Brazil is not Cryptostegia grandiflora as formerly reported. These mycological findings are of greater importance now since C. madagascariensis is likely to become a target for biological control together with its former status in Brazil of an ornamental plant of limited relevance.  相似文献   

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The aye-aye (Daubentonia madagascariensis) is an endangered prosimian primate found only on the island of Madagascar. It is the only extant representative of its family Daubentoniidae. The phylogenetic relationship of this species with other prosimians is unclear. Because a G-banded karyotype forDaubentonia has not previously been reported, blood for preparation of lymphocyte cultures was obtained from one of the four aye-ayes in captivity in the United States. The diploid chromosome number was 30. The karyotype consisted of 14 autosomal metacentrics, 10 autosomal submetacentrics, and 4 autosomal acrocentrics. The similarities between the G-banded chromosomes ofDaubentonia and those ofPropithecus, a member of the Indriidae, support the notion thatDaubentonia has a closer relationship with the Indriidae than with other Lemuriformes or the lorisoids.  相似文献   

12.
Understanding the habitat preferences of a species is critical to the management and conservation of its population. The Critically Endangered greater bamboo lemur, Prolemur simus, is patchily distributed across its geographic range, using a very limited fraction of its total area of occurrence. The ecological basis for this patchy distribution remains largely unexplained. We analyzed the local habitat factors affecting the habitat use of Prolemur simus and densities of one of its primary food sources Madagascar giant bamboo, Cathariostachys madagascariensis. We sampled vegetation and site characteristics along belt transects in mid-altitude rain forest areas of the Ankeniheny–Zahamena rain forest corridor in eastern Madagascar, with (N?=?10) and without (N?=?16) evidence of habitat use by Prolemur simus. In our study site the preferred habitat type of Prolemur simus appears to be primary forest stands with moderate to low levels of human disturbance, greater natural disturbance, high densities of large diameter bamboo, and high structural diversity in tree heights. Cathariostachys madagascariensis appears to exploit canopy gaps created by natural disturbances, and similarly often exploits areas of anthropogenic disturbance. We found the highest densities of bamboo to occur in areas of moderate anthropogenic disturbance, whereas larger diameter culms were associated with lower levels of disturbance and smaller culms with areas of high anthropogenic disturbance. Human use of the forest and protection of the habitat of Prolemur simus are not necessarily incompatible, but our data indicate that the severity and frequency of use should probably be relatively low. Our results suggest that in our study site management strategies that minimize human disturbances, promote structural diversity in tree heights, and maintain relatively high densities of large-culmed bamboo may benefit populations of Prolemur simus.  相似文献   

13.
We tested four reforestation techniques in tropical forest fragments that were damaged by fire in upland Madagascar. We conducted a full‐factorial experiment on the survival of transplanted seedlings of five native tree species in grassland plots adjacent to the forest fragments in the Ambohitantely Forest Reserve. The species studied were Dodonaea madagascariensis, Filicium decipiens, Olea lancea, Podocarpus madagascariensis, and Rhus taratana. A total of 480 seedlings were planted; 207 survived the 15 months of the experiment. The factors examined were distance of the reforestation plots from the forest, mixing of forest soil into the plots, application of chemical fertilizers, experimental shading of plots, and the cover of naturally establishing shrubs. Both increasing the distance of plots from the forest edge and adding chemical fertilizers significantly reduced the survival of all seedlings. The surprising negative effects of fertilization may be partly due to increased competition from naturally establishing shrubs that are adapted to exploit high nitrogen levels. Mixing soil from the forest areas into the plots did not change seedling survival. Shading reduced the survival of D. madagascariensis seedlings and did not increase the survival of any species. These findings suggest that the success of reforestation projects can be increased by planting seedlings close to the existing forest fragments. Reforestation of similar tropical forests is likely to be more successful if efforts are focused on expanding the size of existing fragments of tropical forest, rather than on establishing new fragments in grassland openings.  相似文献   

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Investigation of the endemic Madagascar plant Leptadenia madagascariensis Decne. (Apocynaceae) for antiproliferative activity against the A2780 ovarian cancer cell line led to the isolation of the four new cardenolides 1-4. The structure elucidations of these compounds were based on analyzes of their 1D and 2D NMR spectra and mass spectrometric data. The cardenolides were strongly antiproliferative to the A2780 ovarian cancer cell line, with IC50 values of 0.18, 0.21, 0.17, and 0.29 ??M line, and to the H460 human lung cancer cell line, with IC50 values of 0.16, 0.68, 0.37, and 0.48 ??M, respectively.  相似文献   

16.
Abstract The potential distribution of the herbaceous weed Senecio madagascariensis Poir. (fireweed) in Australia was estimated using the Bioclimate Prediction System, BIOCLIM. Climate profiles for S. madagascariensis predicted that suitable areas occurred only in the south-eastern region of Australia. Its potential to spread outside these areas was assessed by comparing the present African and South American distributions of this species with that observed in Australia. The rate of spread of S. madagascariensis in New South Wales was exponential, although in some regions, such as the Gloucester River Valley, the rates had decreased because all farms had become infested. The results indicate that S. madagascariensis may spread and increase in abundance along the far south coast of New South Wales and in south-eastern Queensland. Coastal areas in eastern Victoria and as far north in Queensland as the Tropic of Capricorn may be invaded.  相似文献   

17.
The aye-aye, Daubentonia madagascariensis, uses its middle digit to tap on woody sources in search of subsurface cavities containing prey. The acoustical properties of these cavities are thought to be important to this percussive foraging, but the contributions of cavity size, configuration, and contents to efficient prey capture are not known. The purpose of this study was to characterize these cavities and their residents. An analysis of foraged trees at two sites in Madagascar revealed that many of the foraged cavities are mines bored by large cerambycid beetle larvae. Apparently cerambycids, as well as inquiline residents of their mines, are major targets of aye-aye foraging behavior. The larvae bore extended mines that course approximately parallel to the long axes of the trees in which they reside. The orientation and large size of the mines offer an acoustical trail that the aye-aye may follow to its prey. © 1995 Wiley-Liss, Inc.  相似文献   

18.
Ten polymorphic microsatellite loci were isolated and characterized from invasive fireweed (Senecio madagascariensis) populations in the Hawaiian archipelago. These loci provided markers with polymorphism of six to 24 alleles per locus within 96 individuals collected from two populations from the island of Maui. The expected and observed heterozygosities ranged from 0.31 to 0.91 and from 0.056 to 1. These markers should be useful to study the importance of genetic diversity in invasion success of this species.  相似文献   

19.
In August 1992 an aye-aye Daubentonia madagascariensis (Primates) was bred in captivity for the first time. This species is the only living representative of a monotypic family and is endangered in its native Madagascar. A brief history of the captive breeding effort and a summary of the conservation problems facing the fauna, flora, and people of Madagascar is given. The role that a captive breeding programme for aye-ayes can fulfil as an aid to preserving biodiversity is discussed.  相似文献   

20.
In the course of a 4-day expedition to the island of Nosy Mangabe in northeastern Madagascar, two aye-ayes were separately sighted, observed feeding and moving, and photographed. These observations confirm recent reports of the continued existence of aye-ayes on the island following the translocation of nine individuals from the mainland in 1967. An adult male aye-aye was seen feeding on the gall-like growths covering much of the bark surface of an Afzelia bijugatree and eating the insects these contained. The same individual also fed briefly on shoots of the bamboo Bambusa vulgaris.  相似文献   

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