Vol. 9 No. (2): 93 - 101 (2018): SEASONAL ADAPTIVE DISTRIBUTION OF MOSQUITO SPECIES IN RICE FIELDS LARVAL HABITATS IN MINNA, NORTH CENTRAL NIGERIA.

Seasonal adaptive distribution of mosquito species in rice fields was investigated in four
widely spaced sites located in Bosso, Maitumbi, Fadikpe and Chanchaga areas of Minna,
Niger State. Mosquito larvae were collected from the four sites during the rainy season
while soil samples were collected by excavation and flooded with water in plastic
containers to allow aestivating eggs and immature to emerge. Immature mosquitoes
recovered for both seasons were reared to adults and identified in the laboratory using
standard morphological keys. The results revealed three mosquito genera (i.e Aedes,
Anopheles and Culex) species co- existing in rice fields in Minna, with Culex been
dominant. The distribution of the ten species of mosquitoes occurred in the following
order of decreasing abundance during the rainy season; Culex pipiens pipiens
651(21.9%)> Culex quinquefasciatus 421(14.2%)> Anopheles gambiae 400 (13.5%)>
Anopheles funestus 334 (11.2%)> Culex restuans 297 1(10.0%)> Anopheles
maculipalpis 187(6.3%)> Anopheles quardrimaculatus 178(6.0%)> Aedes dorsalis 173
(5.8%)> Aedes aegypti 169 (5.7%)> Aedes vexans 162 (5.5%). While that of dry season
was Cx. pipiens pipiens 78(30%)> An. gambiae 6(23%)> Cx. quinquefasciatus 34
(13%)> An.funestus 32 (12.3%)> Ae. aegypti 20 (7.7%)> An. maculipalpis 10 (3.8%)>
An. quadrimaculatus 9(3.4%)> Cx. restuans 8(3.1%)> Ae. dorsalis 6(2.3%)> Ae vexans
4(1.5%). Findings further revealed a negative correlation between Aedes vs Anopheles
and Anopheles vs Culex mosquitoes in rainy season. But a positive correlation was
exhibited between the three mosquito genera during the dry season. Statistically
however, there was significant difference (P > 0.05) in the distribution of mosquito
species in the studied areas in both seasons. Thus, there is an urgent need for an effective
mosquito larvicidal programme for vector control in rice-fields in Minna, for sustainable
rice production.