We studied seed germination and seedling growth performance in an economically and socially important fruit tree species <em>Vitellaria paradoxa</em> C.F. Gaertn. subsp. <em>nilotica</em> (shea...We studied seed germination and seedling growth performance in an economically and socially important fruit tree species <em>Vitellaria paradoxa</em> C.F. Gaertn. subsp. <em>nilotica</em> (shea tree) in Uganda. The study aimed at determining variations in germination among five shea tree seed provenances and seedling growth performance based on five growth traits (total height, root collar diameter, leaf length, leaf width and leaf petiole length). Five populations were considered from four agroecological zones comprising of 180 candidate “plus” trees. The seed trees consisted of 16 ethnovarieties selected based on their traits for fast growth and high oil yield. A total of 1,204 biological seeds were collected and sown in a tree nursery at Ngetta Zonal Agricultural Research and Development Institute during the month of June 2018 in a randomized incomplete block design with three replications. Significant variation (χ = 708;p < 0.01) was observed in seedling phenotypic traits within and between populations. Regression equation for height growth and leaf size index were given as y = 0.3787 + 12.671x and y = 0.6483 + 15.413x respectively. Root collar diameter was more correlated to leaf size index (0.425) than to height growth (0.30). Clustering of shea tree seedlings based on phenotypic growth traits revealed one aggregated cluster indicating that most of the seedlings from the five populations were similar (Jaccard index 0.92, p < 0.01). However, clustering based on SNP markers revealed three different populations. We recorded higher growth (χ = 708;p < 0.001) in Arua shea population. Red seeded;thin pulped and hairy fruited shea tree ethnovarieties recorded faster growth than the rest. The results reveal useful traits in selection for tree growth and further identified shea tree ethnovarieties that could be selected for fast growth.展开更多
Background:Human brucellosis is prevalent in both rural and urban Uganda,yet most cases of the disease in humans go unnoticed and untreated because of inaccurate diagnosis,which is often due to the disease not manifes...Background:Human brucellosis is prevalent in both rural and urban Uganda,yet most cases of the disease in humans go unnoticed and untreated because of inaccurate diagnosis,which is often due to the disease not manifesting in any symptoms.This study was undertaken to describe trends in laboratory-confirmed human brucellosis cases at three health facilities in pastoralist communities in South-western,Uganda.Methods:Data were collected retrospectively to describe trends of brucellosis over a 10-year period(2003–2012),and supplemented with a prospective study,which was conducted from January to December 2013.Two public health facilities and a private clinic that have diagnostic laboratories were selected for these studies.Annual prevalence was calculated and linearly plotted to observe trends of the disease at the health facilities.A modified Poisson regression model was used to estimate the risk ratio(RR)and 95%confidence intervals(CIs)to determine the association between brucellosis and independent variables using the robust error variance.Results:A total of 9,177 persons with suspected brucellosis were identified in the retrospective study,of which 1,318(14.4%)were confirmed cases.Brucellosis cases peaked during the months of April and June,as observed in nearly all of the years of the study,while the most noticeable annual increase(11–23%)was observed from 2010 to 2012.In the prospective study,there were 610 suspected patients at two public health facilities.Of these,194(31.8%)were positive for brucellosis.Respondents aged 45–60 years(RR=0.50;CI:0.29–0.84)and those that tested positive for typhoid(RR=0.68;CI:0.52–0.89)were less likely to have brucellosis.Conclusions:With the noticeable increase in prevalence from 2010 to 2012,diagnosis of both brucellosis and typhoid is important for early detection,and for raising public awareness on methods for preventing brucellosis in this setting.展开更多
文摘We studied seed germination and seedling growth performance in an economically and socially important fruit tree species <em>Vitellaria paradoxa</em> C.F. Gaertn. subsp. <em>nilotica</em> (shea tree) in Uganda. The study aimed at determining variations in germination among five shea tree seed provenances and seedling growth performance based on five growth traits (total height, root collar diameter, leaf length, leaf width and leaf petiole length). Five populations were considered from four agroecological zones comprising of 180 candidate “plus” trees. The seed trees consisted of 16 ethnovarieties selected based on their traits for fast growth and high oil yield. A total of 1,204 biological seeds were collected and sown in a tree nursery at Ngetta Zonal Agricultural Research and Development Institute during the month of June 2018 in a randomized incomplete block design with three replications. Significant variation (χ = 708;p < 0.01) was observed in seedling phenotypic traits within and between populations. Regression equation for height growth and leaf size index were given as y = 0.3787 + 12.671x and y = 0.6483 + 15.413x respectively. Root collar diameter was more correlated to leaf size index (0.425) than to height growth (0.30). Clustering of shea tree seedlings based on phenotypic growth traits revealed one aggregated cluster indicating that most of the seedlings from the five populations were similar (Jaccard index 0.92, p < 0.01). However, clustering based on SNP markers revealed three different populations. We recorded higher growth (χ = 708;p < 0.001) in Arua shea population. Red seeded;thin pulped and hairy fruited shea tree ethnovarieties recorded faster growth than the rest. The results reveal useful traits in selection for tree growth and further identified shea tree ethnovarieties that could be selected for fast growth.
基金The authors are grateful for the financial support from the International Development Research Centre(IDRC),Canada,and the participating laboratories for granting access to the records.
文摘Background:Human brucellosis is prevalent in both rural and urban Uganda,yet most cases of the disease in humans go unnoticed and untreated because of inaccurate diagnosis,which is often due to the disease not manifesting in any symptoms.This study was undertaken to describe trends in laboratory-confirmed human brucellosis cases at three health facilities in pastoralist communities in South-western,Uganda.Methods:Data were collected retrospectively to describe trends of brucellosis over a 10-year period(2003–2012),and supplemented with a prospective study,which was conducted from January to December 2013.Two public health facilities and a private clinic that have diagnostic laboratories were selected for these studies.Annual prevalence was calculated and linearly plotted to observe trends of the disease at the health facilities.A modified Poisson regression model was used to estimate the risk ratio(RR)and 95%confidence intervals(CIs)to determine the association between brucellosis and independent variables using the robust error variance.Results:A total of 9,177 persons with suspected brucellosis were identified in the retrospective study,of which 1,318(14.4%)were confirmed cases.Brucellosis cases peaked during the months of April and June,as observed in nearly all of the years of the study,while the most noticeable annual increase(11–23%)was observed from 2010 to 2012.In the prospective study,there were 610 suspected patients at two public health facilities.Of these,194(31.8%)were positive for brucellosis.Respondents aged 45–60 years(RR=0.50;CI:0.29–0.84)and those that tested positive for typhoid(RR=0.68;CI:0.52–0.89)were less likely to have brucellosis.Conclusions:With the noticeable increase in prevalence from 2010 to 2012,diagnosis of both brucellosis and typhoid is important for early detection,and for raising public awareness on methods for preventing brucellosis in this setting.
