Identity of Fusarium species associated with collar rot and wilt in passion fruit (Passiflora edulis)

Background: Despite the immense contribution of passion fruits to people’s livelihood on a global scale, the crop’s productivity remains low owing to fungal diseases causing up to 100% loss. Fungi are highly variable and the identity of species or variates responsible for recently devastating passion fruit wilt and collar rot diseases had not been characterized. This study was aimed at identifying pathogens causing wilt and collar rot symptoms in passion fruits. Methodology: Fungi were isolated from diseased samples collected from three locations in Central Uganda to identify Fusarium spp associated with collar rot and wilting of passion fruit. This was established by differentiating mycelium pigmentation on Potato Dextrose Agar (PDA), examining slides at X40 magnification under a light microscope for specific macro and microconidia, and amplification with specific Transcription Elongation Factor-1α, TEF 1α primers for identification of Fusarium spp. Results: It was revealed that wilting was associated with a single species, out of 6 selected isolates from the suspected wilted plant, 3 were Fusarium spp associated with the disease in the field but only one of these isolates was proved to be a pathogenic type Fusarium oxysporium. Collar rot was associated with one pathogenic Fusarium spp out of the 6 selected isolates. Conclusion: The results indicate that collar rot and Fusarium wilt are each caused by specific strains of Fusarium pathogens. Recommendation: The identification of pathogenic Fusarium in farmers’ orchards is a starting point for designing effective disease management measures against the predominant fungal pathogenic variants in passion fruits. 

Soil Mineral Status, Plant Ionome and Agro-Morphological Traits of Schkuhria Pinnata (L.), An Antimalarial Herb: Implications for Cultivation

Background: Schkuhria pinnata L., is an antimalarial plant that is highly threatened by the destructive harvesting methods and its collection largely relies on wild sources, that are also exposed to over-exploitation and habitat destruction.Aim of the study: The study aimed at figuring out where S. pinnata grows best and what its growth requirements are; in order to promote the informed cultivation practices and soil selection as a viable alternative to wild harvesting. The agronomical soil nutrient status of S. pinnata, and how it relates to the agro-morphological traits and plant ionome, clues on fertiliser formulations for soils where S. pinnata does not shrive were reported.Methods: A randomised complete block design was employed in agronomical experimental plots in different agro-ecological zones that host Bushenyi, Ntungamo and Kasese districts. Standard procedures for soil and plant analysis were used to analyse soil physicochemical and plant ionome parameters while agro-morphological traits were physically evaluated.Results: Results demonstrated that soil physicochemical characteristics differed significantly across the study sites (p ≤.05). S. pinnata significantly performed better in slightly acidic to neutral soils (pH between 5.87-7.25) in Kasese than in other sites. S. pinnata harvested from Kasese had the largest total leaf area (mean = 31.43 ± 2.41cm2) and the highest plant biomass (mean = 7.65 ± 0.64 g).Conclusion: The study concluded that S. pinnata grew best in slightly acidic to neutral, sandy loam, non-saline soils of Kasese in Western Medium-High Farmlan

Intestinal Schistosomiasis and Giardiasis Co-Infection in Sub-Saharan Africa: Can a One Health Approach Improve Control of Each Waterborne Parasite Simultaneously?

Both intestinal schistosomiasis and giardiasis are co-endemic throughout many areas of sub-Saharan Africa, significantly impacting the health of millions of children within endemic areas. While giardiasis is not considered a neglected tropical disease, intestinal schistosomiasis is formally grouped within the NTD umbrella and, as such, receives significant advocacy and financial support for large-scale control, annually. Given the many epidemiological similarities between intestinal schistosomiasis and giardiasis, in this review, we critically discuss why disease surveillance and control activities for giardiasis are largely absent within low- and middle-income countries. With advances in new methods of parasite diagnostics and provision of existing anti-parasitic medications, better management of intestinal schistosomiasis and giardiasis co-infection could, not only be better understood but also, more effectively controlled. In this light, we appraise the suitability of a One Health approach for intestinal schistosomiasis, for if adopted more broadly, could also pave a way forward for more inclusive public health actions against giardiasis.</jats:p

Genetic diversity of aflatoxin-producing Aspergillus flavus isolated from selected groundnut growing agro-ecological zones of Uganda

Background: Groundnut pre- and post-harvest contamination is commonly caused by fungi from the Genus Aspergillus. Aspergillus flavus is the most important of these fungi. It belongs to section Flavi; a group consisting of aflatoxigenic (A. flavus, A. parasiticus and A. nomius) and non-aflatoxigenic (A. oryzae, A. sojae and A. tamarii) fungi. Aflatoxins are food-borne toxic secondary metabolites of Aspergillus species associated with severe hepatic carcinoma and children stuntedness. Despite the well-known public health significance of aflatoxicosis, there is a paucity of information about the prevalence, genetic diversity and population structure of A. flavus in different groundnut growing agroecological zones of Uganda. This cross-sectional study was therefore conducted to fill this knowledge gap. Results: The overall pre- and post-harvest groundnut contamination rates with A. flavus were 30.0 and 39.2% respectively. Pre- and post-harvest groundnut contamination rates with A. flavus across AEZs were; 2.5 and 50.0%; (West Nile), 55.0 and 35.0% (Lake Kyoga Basin) and 32.5 and 32.5% (Lake Victoria Basin) respectively. There was no significant difference (χ2 =2, p = 0.157) in overall pre- and post-harvest groundnut contamination rates with A. flavus and similarly no significant difference (χ2 =6, p = 0.199) was observed in the pre- and post-harvest contamination of groundnut with A. flavus across the three AEZs. The LKB had the highest incidence of aflatoxin-producing Aspergillus isolates while WN had no single Aspergillus isolate with aflatoxin-producing potential. Aspergillus isolates from the pre-harvest groundnut samples had insignificantly higher incidence of aflatoxin production (χ2= 2.667, p = 0.264) than those from the post-harvest groundnut samples. Overall, A. flavus isolates exhibited moderate level (92%, p = 0.02) of genetic diversity across the three AEZs and low level (8%, p = 0.05) of genetic diversity within the individual AEZs. There was a weak positive correlation (r = 0.1241, p = 0.045) between genetic distance and geographic distance among A. flavus populations in the LKB, suggesting that genetic differentiation in the LKB population might be associated to geographic distance. A very weak positive correlation existed between genetic variation and geographic location in the entire study area (r = 0.01, p = 0.471), LVB farming system (r = 0.0141, p = 0.412) and WN farming system (r= 0.02, p = 0.478). Hierarchical clustering using the unweighted pair group method with arithmetic means (UPGMA) revealed two main clusters of genetically similar A. flavus isolates. Conclusions: These findings provide evidence that genetic differentiation in A. flavus populations is independent of geographic distance. This information can be valuable in the development of a suitable biocontrol management strategy of aflatoxin-producing A. flavus

Farmer knowledge, perceptions and management of maize lethal necrosis disease in selected agro-ecological zones of Uganda

A new disease on the African continent called maize lethal necrosis disease (MLND) that has been reported to cause up to 100% losses in neighbouring Kenya, has since spread to Uganda. Production of maize in Uganda is now under threat from this devastating virus disease. Understanding farmers’ knowledge, perceptions and management practices is a prerequisite to establishing an effective disease nmanagement approach to halt its spread in Uganda. A survey of 396 farmers from 14 major maize growing districts in five agro-ecological zones of Uganda was conducted in 2015 aimed at assessing farmers’ current knowledge of maize lethal necrosis disease and practices for its management. Most farmers (58.1%) had not heard or observed MLN in their fields. The study reveals that 56.6% of the farmers interviewed first experienced MLN in the year 2014. There was uncertainty of the cause of MLN symptoms among 56.6% of the farmers. Most farmers observed MLN symptoms at one month after planting. Only 21.7% correctly identified MLN symptoms observed. The main MLN symptom observed by most farmers (60.6%) was chlorotic mottle on leaves. Up to 55.3% of farmers attempted to control MLN with the majority (77.4%) managing it through uprooting and burning the diseased plants, which they indicated was effective in managing MLN. These results suggest that MLN control could be achieved by enhancing farmers’ knowledge and considering successful farmer MLN management practices when developing and promoting management practices for this disease