No abstract

Pest rodents remain key biotic constraints to cereal crops production in the East African region where they occur, especially in seasons of outbreaks. Despite that, Uganda has scant information on rodents as crop pests to guide effective management strategies. A capture–mark–recapture (CMR) technique was employed to study the ecology of small rodents, specifically to establish the species composition and community structure in a maize‐based agro ecosystem. Trapping of small rodents was conducted in permanent fallow land and cultivated fields, with each category replicated twice making four study grids. At each field, a 60 × 60 m grid was measured and marked with permanent trapping points spaced at 10 × 10 m, making a total of 49 trapping points/grids. Trapping was conducted monthly at 4‐week interval for three consecutive days for two and half years using Sherman live traps. Eleven identified small rodent species and one insectivorous small mammal were recorded with Mastomys natalensis being the most dominant species (over 60.7%). Other species were Mus triton (16.1%), Aethomys hendei (6.7%), Lemniscomys zebra (5.2%), Lophuromys sikapusi (4.8%), Arvicanthis niloticus (0.9%), Gerbilliscus kempi (0.1%), Graphiurus murinus (0.1%), Steatomys parvus (0.1%), Dasymys incomtus (0.1%), and Grammomys dolichurus (0.1%). Spatially, species richness differed significantly ( p = 0.0001) between the studied field habitats with significantly higher richness in fallow land compared with cultivated fields. Temporally, total species richness and abundance showed a significant interaction effect over the months, years, and fields of trapping with significantly ( p = 0.001) higher abundances during months of wet seasons and in the first and third year of trapping. In terms of community structure, higher species diversity associated more with fallow field habitats but also with certain rare species found only in cultivated fields. Synthesis and applications. Based on these findings, management strategies can be designed to target the key pest species and the most vulnerable habitats thus reducing the impact they can inflict on field crops.

A 2.5-year study was conducted to understand the fitness of Mastomys natalensis in an agroecosystem in relationship with environmental predictors. The study was conducted in Mayuge district, in the Lake Victoria Crescent zone in Eastern Uganda. Fitness was measured in terms of survival, maturation and capture probability and estimated using multi-event capture-recapture models. Survival rates were higher after high rainfall in the previous month and increased with increasing population density of the animals. Maturation rate, on the other hand, showed no significant association with any predictor variables, while capture probability was significantly associated with sex of the animals, with higher capture probability for males. The results demonstrate that the fitness of M. natalensis in an agroecosystem is dependent on rainfall, sex and current population density. The aforementioned results were associated with increasing vegetation which provides cover for animal nesting and abundant food for the animals during rainfall periods and thus increased survival, high mobility in males in search for mates thus exposing animals to high chances of being captured and increased prey saturation at high population density resulting in high animal survival. These results have important implications for the timing of management strategies, i.e. control efforts should be enforced during the rainfall seasons to prevent high population buildup in the succeeding seasons.

The cultivated peanut (Arachis hypogaea L.) is one of the most widely consumed legumes globally due to its nutrient content, taste, and affordability. Nutrient composition and consumer preference were determined for twenty local farmer (landrace) and commercial peanut varieties grown in the Nakaseke and Nakasongola districts of the central wooded savanna of Uganda through sensory and laboratory evaluation. Significant differences in nutrient content (p < 0.05) among peanut varieties were found within and across sites. A significant relationship between nutrient content and consumer preference for varieties within and across sites was also realized (Wilk’s lambda = 0.05, p = 0.00). The differences in nutrient content influenced key organoleptic characteristics, including taste, crunchiness, appearance, and soup aroma, which contributed to why consumers may prefer certain varieties to others. Gender differences in variety selection were significantly related to consumer preference for the crunchiness of roasted peanut varieties (F = 5.7, p = 0.016). The results imply that selecting different varieties of peanuts enables consumers to receive different nutrient amounts, while experiencing variety uniqueness. The promotion of peanut intraspecific diversity is crucial for improved nutrition, organoleptic appreciation and the livelihood of those engaged in peanut value chains, especially for the actors who specialize in different peanut products. The conservation of peanut diversity will ensure that the present and future generations benefit from the nutritional content and organoleptic enjoyment that is linked to unique peanut varieties.

Maize lethal necrosis (MLN) is the latest emerging disease of maize in