Documented plants with mosquito repellent properties
Although several plant species with insect-repelling properties exist in the tropics [21], they have mostly remained unexplored, with only a few studies documenting the medicinal plant species used as repellents in Africa in general and in Uganda specifically. Limited documentation has prevented most of these plant species from being scientifically evaluated for thier effectiveness.
Compared with our study, where 42 plant species were documented as being used traditionally for repelling mosquitoes in the West Nile Subregion, uganda, Pavela and Benelli [31] conducted a review of plants used to repel mosquitoes across Africa and reported that natives in Africa (Ethiopia, kenya, Nigeria, South Africa, and Tanzania) traditionally used 64 plants from 30 families. In addition, six plant species specifically used for repelling mosquitoes were previously documented in Cegere, northern Uganda [32]. Similarly, Shibeshi et al. [20] documented 19 plant species used by the local community as mosquito repellents in Seweyna district, Ethiopia, whereas Mavundza et al. [33] documented 23 plant species used in the uMkhanyakude district of KwaZulu-Natal province, South Africa. Moreover, Pålsson and Jaenson [34] documented eight plant species used for repelling mosquitoes in the Oio region of Guinea-Bissau. Seyoum et al. [35] reported eight plant species from Kenya, and Havyarimana et al. [36] reported 12 from Burundi. Kweka et al. [37] reported essential oils from two plant species,Ocimum suave and Ocimum kilimandscharicum,from Northeast Tanzania,which are used as mosquito repellents.
The most commonly used plants for repelling mosquitoes in our study were Azadirachta indica A., Boswellia papyrifera (Caill.), Aeschynomene americana L., Mesosphaerum suaveolens (L.) Kuntze (Syn: Hyptis suaeolens), and Ocimum gratissimum L.These plants contain phytochemicals that exhibit mosquito-repelling properties. such as, two different Boswellia species, Boswellia microphylla and Boswellia neglecta, are among the most commonly used mosquito repellent plants in Ethiopia [20]. The same boswellia species documented in our study (Boswellia papyrifera) was also used by the Oromo people in Ethiopia [38]. Another interesting overlap was the use of a different species of Ocimum (Ocimum ellenbeckii) and two different Acacia species (now Vachellia), Acacia mellifera benth and Acacia bussei Harms.ex.Joste in Ethiopia, whereas V.seyal and V. siberiana were documented in this study.
In Kenya, other than L. camara, the other commonly documented mosquito repellent medicinal plant species (Ocimum americanum L., Tagetes minuta, A. indica, and H. suaveolens) [35] or members of the same genus (O. americanum) were also used as mosquito repellents in this study. In addition, M. azedarach as well as Balanites maughamii Sprague and Balanites aegyptiaca, were documented in South Africa as mosquito repellents [33], and M. azedarach was used among the Oromo people in Ethiopia [38].The similarity in usage across countries supports the ethnobotanical use of these medicinal plants for mosquito repellency by the West Nile community in Uganda.
Similarly, in Guinea-Bissau, Pålsso