Objective:To demonstrate a noninvasive large mammalian genetic sampling method using blood meal obtained from a tabanid fly.Methods:Blood meal was recovered from the abdomen of an engorged tabanid fly(Haematopota sp.)...Objective:To demonstrate a noninvasive large mammalian genetic sampling method using blood meal obtained from a tabanid fly.Methods:Blood meal was recovered from the abdomen of an engorged tabanid fly(Haematopota sp.)which was captured immediately after biting a Sumatran rhino in captivity.The blood was applied on to a Whatman FTAblood card.Subsequent laboratory work was conducted to extract,amplify and sequence the DNA from the sample.Validation was done by sampling the hair follicles and blood samples from the rhinoceros and subjecting it to the same laboratory process.Results:BLAST search and constructed phylogenetic trees confirmed the blood meal samples were indeed from the rhino.Conclusions:This method could be used in the field application to noninvasively collect genetic samples.Collection of tabanids and other haematophagous arthropods(e.g.mosquitoes and ticks)and other blood-sucking parasites(e.g.leeches and worms)could also provide information on vector-borne diseases.展开更多
The majority of wild Sumatran tigers are believed to live in 12 Tiger Conservation Landscapes covering approximately 88000 km^(2).However,the actual distribution of tigers across Sumatra has never been accurately mapp...The majority of wild Sumatran tigers are believed to live in 12 Tiger Conservation Landscapes covering approximately 88000 km^(2).However,the actual distribution of tigers across Sumatra has never been accurately mapped.Over the past 20 years,conservation efforts focused on the Sumatran tigers have increased,but the population continues to decline as a result of several key threats.To identify the status of the Sumatran tiger distribution across the island,an island-wide questionnaire survey comprised of 35 respondents from various backgrounds was conducted between May and June 2010.The survey found that Sumatran tigers are positively present in 27 habitat patches larger than 250 km2 and possibly present in another 2.In addition,a review on major published studies on the Sumatran tiger was conducted to identify the current conservation status of the Sumatran tiger.Collectively,these studies have identified several key factors that have contributed to the decline of Sumatran tiger populations,including:forest habitat fragmentation and loss,direct killing of tigers and their prey,and the retaliatory killing of tigers due to conflict with villagers.The present paper provides management authorities and the international community with a recent assessment and a base map of the actual distribution of Sumatran tigers as well as a general overview on the current status and possible future conservation challenges of Sumatran tiger management.展开更多
65 km Semangko Fault is part of southern segments of Sumatran Fault Zone(SFZ)which is complex corresponds to the transition from the strike-slip regime of the SFZ to the normal faulting tectonics of the Sunda Strait.T...65 km Semangko Fault is part of southern segments of Sumatran Fault Zone(SFZ)which is complex corresponds to the transition from the strike-slip regime of the SFZ to the normal faulting tectonics of the Sunda Strait.The recent publication showed branches of Semangko Fault:West Semangko Fault(WSF)and East Semangko Fault(ESF).This study estimated geodetic slip rate and locking depth of ESF using Global Positioning System(GPS)time series data from 2007 to 2019 from all available GPS sites.GPS velocities refer to Sundaland Plate were used to estimate the fault parameters of the WSF and ESF simultaneously.Non-uniformity of velocity direction shows the complexities of Semangko Fault possibly caused by the contribution of all faults around ESF.An ESF geodetic slip rate,which is 12.5±2 mm/yr was lower than WSF,which is 16.5±2 mm/yr.It is consistent with the rigid block nature of the SFZ system as northern segment slip rates have similar value.Small slip rates are possibly leading to lower generated seismic moment than the major segment of SFZ.展开更多
We aimed to study the response of Conyza sumatrensis to different doses of glufosinate, intrapopulation variation in sensitivity to the herbicide, and the heritability of phenotypic response, and model the evolution o...We aimed to study the response of Conyza sumatrensis to different doses of glufosinate, intrapopulation variation in sensitivity to the herbicide, and the heritability of phenotypic response, and model the evolution of resistance. Three studies were conducted in the greenhouse with two repetitions. First, we tested doses of glufosinate (0, 50, 100, 200, 400, 800 g a.i. ha-1) plus a nontreated check, with four replications. Second, we examined the range in sensitivity of 44 plants to 200 g a.i. ha-1 glufosinate. Third, we evaluated the sensitivity of the progeny of six glufosinate-treated plants to 200 g a.i. ha-1 glufosinate. Plant response was evaluated visually and the ammonium content in leaf tissues was measured. Glufosinate at 400 g a.i. ha-1 caused the highest injury to C.sumatrensis plants. Ammonia accumulation occurred in response to glufosinate treatment, regardless of dose. Ammonia accumulation was correlated strongly with the level of visible plant injury;thus, it is a good indicator of herbicide efficacy. Sensitivity to glufosinate was highly variable within the population. Plants with high ammonia concentration (high injury) after treatment with glufosinate produced progenies that also had high ammonia concentrations after herbicide treatment. The variation in ammonia accumulation among siblings was high. Simulating the exclusion of plants that accumulated more ammonia produced a population that is expected to be less sensitive to glufosinate in the next generation. The stronger the selection pressures by a simulated treatment with glufosinate, the greater the reduction in ammonia accumulation in the progeny and expected sensitivity to glufosinate.展开更多
基金supported by the Sime Darby Foundation(Grant code:P23 071000490001)
文摘Objective:To demonstrate a noninvasive large mammalian genetic sampling method using blood meal obtained from a tabanid fly.Methods:Blood meal was recovered from the abdomen of an engorged tabanid fly(Haematopota sp.)which was captured immediately after biting a Sumatran rhino in captivity.The blood was applied on to a Whatman FTAblood card.Subsequent laboratory work was conducted to extract,amplify and sequence the DNA from the sample.Validation was done by sampling the hair follicles and blood samples from the rhinoceros and subjecting it to the same laboratory process.Results:BLAST search and constructed phylogenetic trees confirmed the blood meal samples were indeed from the rhino.Conclusions:This method could be used in the field application to noninvasively collect genetic samples.Collection of tabanids and other haematophagous arthropods(e.g.mosquitoes and ticks)and other blood-sucking parasites(e.g.leeches and worms)could also provide information on vector-borne diseases.
文摘The majority of wild Sumatran tigers are believed to live in 12 Tiger Conservation Landscapes covering approximately 88000 km^(2).However,the actual distribution of tigers across Sumatra has never been accurately mapped.Over the past 20 years,conservation efforts focused on the Sumatran tigers have increased,but the population continues to decline as a result of several key threats.To identify the status of the Sumatran tiger distribution across the island,an island-wide questionnaire survey comprised of 35 respondents from various backgrounds was conducted between May and June 2010.The survey found that Sumatran tigers are positively present in 27 habitat patches larger than 250 km2 and possibly present in another 2.In addition,a review on major published studies on the Sumatran tiger was conducted to identify the current conservation status of the Sumatran tiger.Collectively,these studies have identified several key factors that have contributed to the decline of Sumatran tiger populations,including:forest habitat fragmentation and loss,direct killing of tigers and their prey,and the retaliatory killing of tigers due to conflict with villagers.The present paper provides management authorities and the international community with a recent assessment and a base map of the actual distribution of Sumatran tigers as well as a general overview on the current status and possible future conservation challenges of Sumatran tiger management.
基金funded by Institut Teknologi Sumatera Smart Mandiri 2019 Research Grant Fund No.B/364/IT9.C1/PT.01.03/2019
文摘65 km Semangko Fault is part of southern segments of Sumatran Fault Zone(SFZ)which is complex corresponds to the transition from the strike-slip regime of the SFZ to the normal faulting tectonics of the Sunda Strait.The recent publication showed branches of Semangko Fault:West Semangko Fault(WSF)and East Semangko Fault(ESF).This study estimated geodetic slip rate and locking depth of ESF using Global Positioning System(GPS)time series data from 2007 to 2019 from all available GPS sites.GPS velocities refer to Sundaland Plate were used to estimate the fault parameters of the WSF and ESF simultaneously.Non-uniformity of velocity direction shows the complexities of Semangko Fault possibly caused by the contribution of all faults around ESF.An ESF geodetic slip rate,which is 12.5±2 mm/yr was lower than WSF,which is 16.5±2 mm/yr.It is consistent with the rigid block nature of the SFZ system as northern segment slip rates have similar value.Small slip rates are possibly leading to lower generated seismic moment than the major segment of SFZ.
文摘We aimed to study the response of Conyza sumatrensis to different doses of glufosinate, intrapopulation variation in sensitivity to the herbicide, and the heritability of phenotypic response, and model the evolution of resistance. Three studies were conducted in the greenhouse with two repetitions. First, we tested doses of glufosinate (0, 50, 100, 200, 400, 800 g a.i. ha-1) plus a nontreated check, with four replications. Second, we examined the range in sensitivity of 44 plants to 200 g a.i. ha-1 glufosinate. Third, we evaluated the sensitivity of the progeny of six glufosinate-treated plants to 200 g a.i. ha-1 glufosinate. Plant response was evaluated visually and the ammonium content in leaf tissues was measured. Glufosinate at 400 g a.i. ha-1 caused the highest injury to C.sumatrensis plants. Ammonia accumulation occurred in response to glufosinate treatment, regardless of dose. Ammonia accumulation was correlated strongly with the level of visible plant injury;thus, it is a good indicator of herbicide efficacy. Sensitivity to glufosinate was highly variable within the population. Plants with high ammonia concentration (high injury) after treatment with glufosinate produced progenies that also had high ammonia concentrations after herbicide treatment. The variation in ammonia accumulation among siblings was high. Simulating the exclusion of plants that accumulated more ammonia produced a population that is expected to be less sensitive to glufosinate in the next generation. The stronger the selection pressures by a simulated treatment with glufosinate, the greater the reduction in ammonia accumulation in the progeny and expected sensitivity to glufosinate.
