The influence of weather variables on mango fruit flies abundance and their management in selected agro-ecological zones of Uganda

Abstract

Mango fruit flies pose a considerable challenge to mango production, considerably impacting both yield and fruit quality. Despite the recognized importance of weather variability as a key determinant of pest populations and their associated damage, the existing literature on the relationship between local meteorological conditions and the population dynamics of mango fruit flies in Uganda is limited. This study was set out to assess (i) the influence of weather on the abundance of mango fruit flies in two different agro-ecological zones of Uganda, (ii) assess mango farmers’ knowledge and perceptions towards the management of mango fruit flies, and (iii) to examine farmers’ management practices of mango fruit flies. Two agro-ecological zones of Kyoga Plains and Para savannah with representative districts of Soroti and Nwoya respectively were used for this study. A case study design was used to conduct in-depth investigations on the mango fruit flies’ population of two genera, including Bactrocera, and Ceratitis, under different weather conditions. Four mango farms, 2 in each district, were selected based on fruit fly monitoring guidelines and used as case studies. The stud y also utilized a descriptive cross-sectional research design to collect quantitative data from 192 farmers. The study found that the genus Bactrocera was more abundant with 98.6% of total individuals captured as compared to Ceratitis in both districts. There were significant positive relationships between the abundance of Bactrocera and weather variables of temperature 6and surface pressure in both Nwoya and Soroti districts. However, wind speed showed significant relationship with the abundance of Bactrocera, but not Ceratitis, and only in Nwoya district. There was no observed significant influence of any weather variable on Ceratitis. It was noted that while the majority of mango fruit farmers had good knowledge of managing mango fruit flies, their perception on mango fruit fly management is neutral across all agro-ecological zones. It was revealed that mango fruit farmers employed various methods to control the mango fruit fly such as removing and destroying infested mangoes, using synthetic pesticides and use of traps. Additionally, mango fruit farmers faced challenges such as financial constraints, limited knowledge of pesticides, among others. The study concluded that some, but not all, weather variables can influence the abundance of mango fruit flies, and that the influence may vary among different agro-ecological zones. It is also concluded that farmers’ management practices of mango fruit flies and challenges vary with agro-ecological zones implying that strategies to support farmers in managing the mango fruit flies should consider the specific dynamics of each agro-ecological zone.