22 research outputs found
Locust and grasshopper outbreaks in Zululand sugarcane, Kwazulu-Natal, South Africa
Thesis (MScConEcol)--Stellenbosch University, 2014.ENGLISH ABSTRACT: The aim of the research presented in this dissertation was to investigate localised acridid outbreaks causing damage to sugarcane in Empangeni, Kwazulu-Natal, South Africa. Reports of outbreaks with increasing severity have occurred for the last six or seven years, which prompted this research. In general, little is known about acridid outbreaks in sugarcane due to their sporadic nature, therefore this project set out to identify morphologically and molecularly, all species associated with Empangeni sugarcane and to determine the ecology and population dynamics of the most important species, to provide baseline data for the development of an integrated pest management (IPM) plan against these crop pests.
A year-long population survey was conducted on a number of affected farms and adjacent grassland sites to determine the life cycles, population density and composition of this acridid complex on these farms. Surveys showed that this complex comprised five species: Nomadacris septemfasciata, Petamella prosternalis, Ornithacris cyanea, Cyrtacanthacris aeruginosa and Cataloipus zuluensis. Observed damage was recorded throughout the year in order to correlate with species densities. It was found that damage was closely associated with two species, namely Petamella prosternalis and Nomadacris septemfasciata, therefore these two species are of particular concern due to their higher densities and large body size resulting in them being the biggest threat to Empangeni sugarcane. All five species are univoltine but two different life cycle strategies were discovered, 3 species exhibit a winter egg diapause while 2 species exhibit a winter adult reproductive diapause, an important finding considering the knowledge intensive method of control which has been proposed. Population surveys revealed a large difference in species composition among farms (sugarcane sites) and among grassland sites. Nomadacris septemfasciata and Petamella prosternalis showed a significant preference for sugarcane while species such as Cyrtacanthacris aeruginosa, Zonocerus elegans and Orthocta sp. seemed to prefer grassland sites. Feeding potential trials were completed on the two most economically important species, Nomadacris septemfasciata and Petamella prosternalis. The results showed that Petamella prosternalis has a significantly higher feeding potential (% leaf damage) compared to Nomadacris septemfasciata even though in terms of dry weight and length, it is a smaller specimen. Feeding data were used to determine the voracity of these two species under laboratory conditions. Petamella prosternalis eats roughly 1.83 grams of fresh sugarcane per day while Nomadacris septemfasciata eats approximately 1.16 grams per day. These results were then compared to observed field damage data in order to gauge their accuracy and applicability within a field setting, which showed that although sugarcane field damage is significantly correlated with the population fluctuations of both these species, it is more closely associated with Petamella prosternalis resulting in a correlation coefficient of 0.429143 while Nomadacris septemfasciata had a correlation coefficient of 0.250.
Phase polyphenism in the red locust Nomadacris septemfasciata was investigated using three methods including traditional morphometrics (Elytra/Femur (E/F) ratio), hopper colouration and eye stripe data. The E/F ratio indicated that the majority of the Empangeni population sampled is in the transiens and gregarious phase with a mean E/F ratio of 2.0063 and that they seem to be becoming more gregarious over time, with populations in 2012 having a mean E/F ratio of 1.9973 and in 2013 a mean E/F ratio of 2.01315. Hopper colouration also indicates that populations are generally showing gregarious tendencies with the majority of hoppers exhibiting gregarious type colouration. Eye stripe data showed that the majority of adult specimens observed had seven eye stripes, an indication of gregarious individuals. Geometric morphometrics, a relatively new, software based technique which has not been used in phase polyphenism studies before was used as a means to accurately measure variations among populations of N. septemfasciata by measuring the variation in forewing shape according to allocated landmarks. The resulting shape variation were compared to traditional morphometrics in an attempt to relate the two techniques so that geometric morphometrics can possibly be used as a tool to study phase polyphenism in locusts in the future. The results indicate that similarities in terms of location and gender exist between the two methods, however the exact same individuals should be used for both methods which will improve the accuracy of comparisons.
This study, for the first time identified the acridid complex causing damage to Empangeni sugarcane and provided a broad summary of the potential impact the complex has on the crop as well as what may be causing them to occur in this area such as optimal habitat conditions and sugarcane as a preferable host plant being two factors which are likely to be having an influence. The findings of this study provide the baseline data needed in order to develop a more integrated and sustainable approach to controlling these acridids pests. Understanding the biology of the species enables practitioners to make more effective management decisions which is clearly needed as the current techniques being used have not solved the ‘grasshopper problem’.AFRIKAANSE OPSOMMING: Die doel van die navorsing wat in hierdie verhandeling was om ondersoek in te gelokaliseerde acridid uitbrekings veroorsaak skade aan suikerriet in Empangeni, KwaZulu-Natal, Suid-Afrika. Verslae van die uitbreek met toenemende erns plaasgevind het vir die laaste 6-7 jaar, wat gelei het tot hierdie navorsing. In die algemeen, is min bekend oor acridid uitbreek in suikerriet as gevolg van hul sporadiese aard, daarom is hierdie projek uiteengesit morfologies en molekulêre identifiseer, al die spesies wat verband hou met Empangeni suikerriet en die ekologie en bevolkingsdinamika van die belangrikste spesies te bepaal, te voorsien basislyn data vir die ontwikkeling van 'n geïntegreerde plaagbestuur (GPB) plan teen hierdie oes peste.
'N jaar lank bevolking opname is uitgevoer op 'n aantal plase wat geraak is en aangrensende grasveld plekke om die lewensiklus te bepaal, bevolkingsdigtheid en samestelling van hierdie acridid kompleks op die plase . Opnames het getoon dat hierdie komplekse bestaan uit vyf spesies: Nomadacris septemfasciata, Petamella prosternalis, Ornithacris Cyanea, Cyrtacanthacris aeruginosa en Cataloipus zuluensis Waargeneem skade is aangeteken deur die jaar ten einde te ooreenstem met spesie digtheid. Daar is gevind dat die skade was nou verbind met twee spesies, naamlik P. prosternalis en N. septemfasciata, dus is die twee spesies van besondere belang as gevolg van hul hoër digtheid en 'n groot liggaam grootte lei daartoe dat hulle die grootste bedreiging vir die Empangeni suikerriet. Al vyf spesies is univoltine maar twee verskillende lewensiklus strategieë ontdek, 3 spesies toon 'n winter eier diapouse terwyl 2 spesies toon 'n winter volwasse reproduktiewe diapouse, 'n belangrike bevinding oorweging van die kennis intensiewe metode van beheer wat is voorgestel. Bevolking opnames openbaar 'n groot verskil in spesies samestelling onder plase (suikerriet webwerwe) en onder grasveld webwerwe. Nomadacris septemfasciata en Petamella prosternalis het 'n beduidende voorkeur vir suikerriet, terwyl spesies soos Cyrtacanthacris aeruginosa, Zonocerus elegans en Orthocta SP. gelyk grasveld webwerwe te verkies. Voeding potensiaal proewe is op die twee mees ekonomies belangrike spesies voltooi, Nomadacris septemfasciata en Petamella prosternalis Die resultate het getoon dat Petamella prosternalis het 'n aansienlik hoër voeding potensiaal(% blaarskade) in vergelyking met Nomadacris septemfasciata selfs al in terme van droë gewig en lengte, is dit is 'n kleiner model. Voeding data is gebruik om die gulzig van hierdie twee spesies onder laboratorium toestande te bepaal. Petamella prosternalis eet ongeveer 1.83 gram vars suikerriet per dag, terwyl Nomadacris septemfasciata eet ongeveer 1,16 gram per dag. Hierdie resultate is dan in vergelyking met waargeneem veld skade data om die akkuraatheid en toepaslikheid in 'n veld omgewing, wat getoon het dat hoewel suikerriet veld skade beduidend gekorreleer met die bevolking skommelinge van beide hierdie spesies, is nouer dit verband hou met Petamella prosternalis te meet lei tot 'n korrelasie koëffisiënt van 0.429143 terwyl Nomadacris septemfasciata het 'n korrelasie koëffisiënt van 0.250408 Fase polyphenism in die rooisprinkaan Nomadacris septemfasciata is ondersoek met behulp van drie metodes, insluitend tradisionele Morphometricsveld (Elytra/Femur (E/F) verhouding), hopper kleur en oog streep data. Die Elytra te Femur verhouding (E/F -verhouding) het aangedui dat die meerderheid van die bevolking is Empangeni in die transiens en gesellige fase met 'n gemiddelde E/F verhouding van 2,0063 en dat dit lyk asof hulle meer kuddedier met verloop van tyd, met bevolkings in 2012 met 'n gemiddelde E/F verhouding van 1,9973 en in 2013 'n gemiddelde E/F verhouding van 2,01315 . Hopper kleur dui ook aan dat die bevolking in die algemeen toon kuddedier neigings Thye meerderheid van hoppers uitstal gesellige tipe kleur. Oog streep het getoon dat die meerderheid van die volwasse eksemplare waargeneem het sewe oog strepe: 'n aanduiding van die gesellige individue. Geometriese Morphometricsveld, 'n relatief nuwe, sagteware gebaseer tegniek wat nie gebruik is in fase polyphenism studies voor was gebruik as 'n middel tot verskille tussen bevolkings van die rooisprinkaan akkuraat te meet deur die variasie meet in voorvlerk vorm volgens toegeken landmerke Die gevolglike vorm variasie is in vergelyking met die tradisionele Morphometricsveld in 'n poging om die twee tegnieke in verband te bring , sodat meetkundige Morphometricsveld kan moontlik as 'n instrument fase polyphenism om te studeer in sprinkane in die toekoms gebruik kan word. Die resultate dui daarop dat die ooreenkomste in terme van ligging en geslag bestaan tussen die twee metodes is egter presies dieselfde individue moet gebruik word vir beide metodes wat die akkuraatheid van vergelykings verbeter.
Hierdie studie, wat vir die eerste keer geïdentifiseer die acridid kompleks om skade aan Empangeni suikerriet en verskaf 'n breë opsomming van die potensiële impak van die kompleks het op die gewas sowel as wat kan veroorsaak word om hulle te kom in hierdie gebied soos optimale habitat toestande en suikerriet as 'n beter gasheer plant. Die bevindinge van hierdie studie verskaf die basislyn data wat nodig is om 'n meer geïntegreerde en volhoubare benadering tot die beheer van hulle as die begrip van die biologie van die spesie in staat stel om praktisyns meer effektiewe bestuur besluite wat duidelik nodig is as 'n die huidige tegnieke gebruik moet maak om te ontwikkel nie opgelos die "sprinkaan probleem"
Acridid ecology in the sugarcane agro-ecosystem in the Zululand region of KwaZulu-Natal, South Africa
CITATION: Bam, A., Addison, P. & Conlong, D. 2020. Acridid ecology in the sugarcane agro-ecosystem in the Zululand region of KwaZulu-Natal, South Africa. Journal of Orthoptera Research, 29(1):9–16, doi:10.3897/jor.29.34626.The original publication is available at https://jor.pensoft.netGrasshoppers and locusts are well known crop and pasture pests throughout the world. Periodically they cause extensive damage to large areas of crops and grazing lands, which often exacerbate food shortage issues in many countries. In South Africa, acridid outbreaks rarely reach economic proportions, but in sugarcane plantations, localized outbreaks of native acridid species have been reported for the last eight years with increasing frequency and intensity in certain areas. This study was undertaken from May 2012 to May 2013 to identify the economically important acridid species in the sugarcane agroecosystem in these outbreak areas, to monitor seasonal activity patterns, to assess sampling methods, and to determine the pest status of the major species through damage ratings. Five acridid species of particular importance were identified: Nomadacris septemfasciata (Serville), Petamella prosternalis (Karny), Ornithacris cyanea (Stoll), Cataloipus zuluensis Sjötedt, and Cyrtacanthacris aeruginosa (Stoll). All species are univoltine. Petamella prosternalis was the most abundant species and exhibited a winter egg diapause, while N. septemfasciata, the second most abundant species, exhibited a winter reproductive diapause. Petamella prosternalis and N. septemfasciata were significantly correlated with the damage-rating index, suggesting that these two species were responsible for most of the feeding damage found on sugarcane. This study, for the first time, identified the acridid species complex causing damage to sugarcane in the Zululand area of KwaZulu-Natal, South Africa, and documented their population characteristics and related damage. These data are important information on which to base sound integrated pest management strategies.SASRINational Research Foundation of South Africahttps://jor.pensoft.net/article/34626/element/8/64680//Publisher's versio
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation
Locust and grasshopper outbreaks in Zululand sugarcane, Kwazulu-Natal, South Africa
Thesis (MScConEcol)--Stellenbosch University, 2014.ENGLISH ABSTRACT: The aim of the research presented in this dissertation was to investigate localised acridid outbreaks causing damage to sugarcane in Empangeni, Kwazulu-Natal, South Africa. Reports of outbreaks with increasing severity have occurred for the last six or seven years, which prompted this research. In general, little is known about acridid outbreaks in sugarcane due to their sporadic nature, therefore this project set out to identify morphologically and molecularly, all species associated with Empangeni sugarcane and to determine the ecology and population dynamics of the most important species, to provide baseline data for the development of an integrated pest management (IPM) plan against these crop pests.
A year-long population survey was conducted on a number of affected farms and adjacent grassland sites to determine the life cycles, population density and composition of this acridid complex on these farms. Surveys showed that this complex comprised five species: Nomadacris septemfasciata, Petamella prosternalis, Ornithacris cyanea, Cyrtacanthacris aeruginosa and Cataloipus zuluensis. Observed damage was recorded throughout the year in order to correlate with species densities. It was found that damage was closely associated with two species, namely Petamella prosternalis and Nomadacris septemfasciata, therefore these two species are of particular concern due to their higher densities and large body size resulting in them being the biggest threat to Empangeni sugarcane. All five species are univoltine but two different life cycle strategies were discovered, 3 species exhibit a winter egg diapause while 2 species exhibit a winter adult reproductive diapause, an important finding considering the knowledge intensive method of control which has been proposed. Population surveys revealed a large difference in species composition among farms (sugarcane sites) and among grassland sites. Nomadacris septemfasciata and Petamella prosternalis showed a significant preference for sugarcane while species such as Cyrtacanthacris aeruginosa, Zonocerus elegans and Orthocta sp. seemed to prefer grassland sites. Feeding potential trials were completed on the two most economically important species, Nomadacris septemfasciata and Petamella prosternalis. The results showed that Petamella prosternalis has a significantly higher feeding potential (% leaf damage) compared to Nomadacris septemfasciata even though in terms of dry weight and length, it is a smaller specimen. Feeding data were used to determine the voracity of these two species under laboratory conditions. Petamella prosternalis eats roughly 1.83 grams of fresh sugarcane per day while Nomadacris septemfasciata eats approximately 1.16 grams per day. These results were then compared to observed field damage data in order to gauge their accuracy and applicability within a field setting, which showed that although sugarcane field damage is significantly correlated with the population fluctuations of both these species, it is more closely associated with Petamella prosternalis resulting in a correlation coefficient of 0.429143 while Nomadacris septemfasciata had a correlation coefficient of 0.250.
Phase polyphenism in the red locust Nomadacris septemfasciata was investigated using three methods including traditional morphometrics (Elytra/Femur (E/F) ratio), hopper colouration and eye stripe data. The E/F ratio indicated that the majority of the Empangeni population sampled is in the transiens and gregarious phase with a mean E/F ratio of 2.0063 and that they seem to be becoming more gregarious over time, with populations in 2012 having a mean E/F ratio of 1.9973 and in 2013 a mean E/F ratio of 2.01315. Hopper colouration also indicates that populations are generally showing gregarious tendencies with the majority of hoppers exhibiting gregarious type colouration. Eye stripe data showed that the majority of adult specimens observed had seven eye stripes, an indication of gregarious individuals. Geometric morphometrics, a relatively new, software based technique which has not been used in phase polyphenism studies before was used as a means to accurately measure variations among populations of N. septemfasciata by measuring the variation in forewing shape according to allocated landmarks. The resulting shape variation were compared to traditional morphometrics in an attempt to relate the two techniques so that geometric morphometrics can possibly be used as a tool to study phase polyphenism in locusts in the future. The results indicate that similarities in terms of location and gender exist between the two methods, however the exact same individuals should be used for both methods which will improve the accuracy of comparisons.
This study, for the first time identified the acridid complex causing damage to Empangeni sugarcane and provided a broad summary of the potential impact the complex has on the crop as well as what may be causing them to occur in this area such as optimal habitat conditions and sugarcane as a preferable host plant being two factors which are likely to be having an influence. The findings of this study provide the baseline data needed in order to develop a more integrated and sustainable approach to controlling these acridids pests. Understanding the biology of the species enables practitioners to make more effective management decisions which is clearly needed as the current techniques being used have not solved the ‘grasshopper problem’.AFRIKAANSE OPSOMMING: Die doel van die navorsing wat in hierdie verhandeling was om ondersoek in te gelokaliseerde acridid uitbrekings veroorsaak skade aan suikerriet in Empangeni, KwaZulu-Natal, Suid-Afrika. Verslae van die uitbreek met toenemende erns plaasgevind het vir die laaste 6-7 jaar, wat gelei het tot hierdie navorsing. In die algemeen, is min bekend oor acridid uitbreek in suikerriet as gevolg van hul sporadiese aard, daarom is hierdie projek uiteengesit morfologies en molekulêre identifiseer, al die spesies wat verband hou met Empangeni suikerriet en die ekologie en bevolkingsdinamika van die belangrikste spesies te bepaal, te voorsien basislyn data vir die ontwikkeling van 'n geïntegreerde plaagbestuur (GPB) plan teen hierdie oes peste.
'N jaar lank bevolking opname is uitgevoer op 'n aantal plase wat geraak is en aangrensende grasveld plekke om die lewensiklus te bepaal, bevolkingsdigtheid en samestelling van hierdie acridid kompleks op die plase . Opnames het getoon dat hierdie komplekse bestaan uit vyf spesies: Nomadacris septemfasciata, Petamella prosternalis, Ornithacris Cyanea, Cyrtacanthacris aeruginosa en Cataloipus zuluensis Waargeneem skade is aangeteken deur die jaar ten einde te ooreenstem met spesie digtheid. Daar is gevind dat die skade was nou verbind met twee spesies, naamlik P. prosternalis en N. septemfasciata, dus is die twee spesies van besondere belang as gevolg van hul hoër digtheid en 'n groot liggaam grootte lei daartoe dat hulle die grootste bedreiging vir die Empangeni suikerriet. Al vyf spesies is univoltine maar twee verskillende lewensiklus strategieë ontdek, 3 spesies toon 'n winter eier diapouse terwyl 2 spesies toon 'n winter volwasse reproduktiewe diapouse, 'n belangrike bevinding oorweging van die kennis intensiewe metode van beheer wat is voorgestel. Bevolking opnames openbaar 'n groot verskil in spesies samestelling onder plase (suikerriet webwerwe) en onder grasveld webwerwe. Nomadacris septemfasciata en Petamella prosternalis het 'n beduidende voorkeur vir suikerriet, terwyl spesies soos Cyrtacanthacris aeruginosa, Zonocerus elegans en Orthocta SP. gelyk grasveld webwerwe te verkies. Voeding potensiaal proewe is op die twee mees ekonomies belangrike spesies voltooi, Nomadacris septemfasciata en Petamella prosternalis Die resultate het getoon dat Petamella prosternalis het 'n aansienlik hoër voeding potensiaal(% blaarskade) in vergelyking met Nomadacris septemfasciata selfs al in terme van droë gewig en lengte, is dit is 'n kleiner model. Voeding data is gebruik om die gulzig van hierdie twee spesies onder laboratorium toestande te bepaal. Petamella prosternalis eet ongeveer 1.83 gram vars suikerriet per dag, terwyl Nomadacris septemfasciata eet ongeveer 1,16 gram per dag. Hierdie resultate is dan in vergelyking met waargeneem veld skade data om die akkuraatheid en toepaslikheid in 'n veld omgewing, wat getoon het dat hoewel suikerriet veld skade beduidend gekorreleer met die bevolking skommelinge van beide hierdie spesies, is nouer dit verband hou met Petamella prosternalis te meet lei tot 'n korrelasie koëffisiënt van 0.429143 terwyl Nomadacris septemfasciata het 'n korrelasie koëffisiënt van 0.250408 Fase polyphenism in die rooisprinkaan Nomadacris septemfasciata is ondersoek met behulp van drie metodes, insluitend tradisionele Morphometricsveld (Elytra/Femur (E/F) verhouding), hopper kleur en oog streep data. Die Elytra te Femur verhouding (E/F -verhouding) het aangedui dat die meerderheid van die bevolking is Empangeni in die transiens en gesellige fase met 'n gemiddelde E/F verhouding van 2,0063 en dat dit lyk asof hulle meer kuddedier met verloop van tyd, met bevolkings in 2012 met 'n gemiddelde E/F verhouding van 1,9973 en in 2013 'n gemiddelde E/F verhouding van 2,01315 . Hopper kleur dui ook aan dat die bevolking in die algemeen toon kuddedier neigings Thye meerderheid van hoppers uitstal gesellige tipe kleur. Oog streep het getoon dat die meerderheid van die volwasse eksemplare waargeneem het sewe oog strepe: 'n aanduiding van die gesellige individue. Geometriese Morphometricsveld, 'n relatief nuwe, sagteware gebaseer tegniek wat nie gebruik is in fase polyphenism studies voor was gebruik as 'n middel tot verskille tussen bevolkings van die rooisprinkaan akkuraat te meet deur die variasie meet in voorvlerk vorm volgens toegeken landmerke Die gevolglike vorm variasie is in vergelyking met die tradisionele Morphometricsveld in 'n poging om die twee tegnieke in verband te bring , sodat meetkundige Morphometricsveld kan moontlik as 'n instrument fase polyphenism om te studeer in sprinkane in die toekoms gebruik kan word. Die resultate dui daarop dat die ooreenkomste in terme van ligging en geslag bestaan tussen die twee metodes is egter presies dieselfde individue moet gebruik word vir beide metodes wat die akkuraatheid van vergelykings verbeter.
Hierdie studie, wat vir die eerste keer geïdentifiseer die acridid kompleks om skade aan Empangeni suikerriet en verskaf 'n breë opsomming van die potensiële impak van die kompleks het op die gewas sowel as wat kan veroorsaak word om hulle te kom in hierdie gebied soos optimale habitat toestande en suikerriet as 'n beter gasheer plant. Die bevindinge van hierdie studie verskaf die basislyn data wat nodig is om 'n meer geïntegreerde en volhoubare benadering tot die beheer van hulle as die begrip van die biologie van die spesie in staat stel om praktisyns meer effektiewe bestuur besluite wat duidelik nodig is as 'n die huidige tegnieke gebruik moet maak om te ontwikkel nie opgelos die "sprinkaan probleem"
Acridid ecology in the sugarcane agro-ecosystem in the Zululand region of KwaZulu-Natal, South Africa
Grasshoppers and locusts are well known crop and pasture pests throughout the world. Periodically they cause extensive damage to large areas of crops and grazing lands, which often exacerbate food shortage issues in many countries. In South Africa, acridid outbreaks rarely reach economic proportions, but in sugarcane plantations, localized outbreaks of native acridid species have been reported for the last eight years with increasing frequency and intensity in certain areas. This study was undertaken from May 2012 to May 2013 to identify the economically important acridid species in the sugarcane agroecosystem in these outbreak areas, to monitor seasonal activity patterns, to assess sampling methods, and to determine the pest status of the major species through damage ratings. Five acridid species of particular importance were identified: Nomadacris septemfasciata (Serville), Petamella prosternalis (Karny), Ornithacris cyanea (Stoll), Cataloipus zuluensis Sjötedt, and Cyrtacanthacris aeruginosa (Stoll). All species are univoltine. Petamella prosternalis was the most abundant species and exhibited a winter egg diapause, while N. septemfasciata, the second most abundant species, exhibited a winter reproductive diapause. Petamella prosternalis and N. septemfasciata were significantly correlated with the damage-rating index, suggesting that these two species were responsible for most of the feeding damage found on sugarcane. This study, for the first time, identified the acridid species complex causing damage to sugarcane in the Zululand area of KwaZulu-Natal, South Africa, and documented their population characteristics and related damage. These data are important information on which to base sound integrated pest management strategies
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A pharmacogenetic candidate gene study of tenofovir-associated Fanconi syndrome
BackgroundTenofovir disoproxil fumarate (TDF) is a widely used antiretroviral agent with favorable efficacy, safety, and tolerability profiles. However, renal adverse events, including the rare Fanconi syndrome (FS), may occur in a small subset of patients treated for HIV infections.ObjectivesThe aim of this study was to identify genetic variants that may be associated with TDF-associated FS (TDF-FS).MethodsDNA samples collected from 19 cases with TDF-FS and 36 matched controls were sequenced, and genetic association studies were conducted on eight candidate genes: ATP-binding cassette (ABC) transporters ABCC2 (MRP2) and ABCC4 (MRP4), solute carrier family members SLC22A6 (OAT1) and SLC22A8 (OAT3), adenylate kinases 2 (AK2) and 4 (AK4), chloride transporter CIC-5 CLCN5, and Lowe syndrome protein OCRL. The functional effects of a single nucleotide polymorphism (SNP) predicted to alter the transport of tenofovir were then investigated in cells expressing an identified variant of ABCC4.ResultsThe case group showed a trend toward a higher proportion of rare alleles. Six SNPs in ABCC2 (three SNPs), ABCC4 (one SNP), and OCRL (two SNPs) were associated with TDF-FS case status; however, this association did not remain significant after correction for multiple testing. Six SNPs, present in OCRL (four SNPs) and ABCC2 (two SNPs), were significantly associated with increased serum creatinine levels in the cases, and this association remained significant after multiple test correction (P < 2 × 10). One synonymous SNP in ABCC2 (rs8187707, P = 2.10 × 10, β = -73.3 ml/min/1.73 m(2)) was also significantly associated with the decreased estimated glomerular filtration rate of creatinine among cases. However, these results were driven by rare SNPs present in a small number of severely affected cases. Finally, a previously uncharacterized, nonsynonymous SNP, rs11568694, that was predicted to alter MRP4 function had no significant effect on tenofovir cellular accumulation in vitro.ConclusionAlthough no single predictive genetic marker for the development of TDF-FS was identified, the findings from our study suggest that rare variants in multiple genes involved in the renal handling of tenofovir, and/or renal cell homeostasis, may be associated with increased susceptibility to TDF-FS