EFFECT OF N-P FERTILIZERS AND COW DUNG ON THE LARVAL DEVELOPMENT OF MOSQUITOES IN SIMULATED FIELD IN ALAGAE, CENTRAL ETHIOPIA

Abstract

Objective: This study was conducted to assess the effect of N-P fertilizers and cow dung on mosquito larva development at
Alagae, Central Ethiopia, from January 2007 to February 2007.
Methods: Cow dung, Urea and DAP were applied in thirty-three experimental ponds of 50 cm radius wide and 19 cm deep.
Results: Application of these fertilizers resulted in varied larval count of culicines and anophelines mosquito species. Culicine mosquito larvae count (83.1% and 97.2%) was higher than that of anophelines (16.9% and 2.8%) in manure and N-P
treated ponds respectively. Higher larval number was collected in ponds treated with both cow dung and N-P fertilizers
(87.7%) than the control (12.3%), (P<0.001). Moreover, application of these fertilizers in a pond resulted in three-fold increase in larval population when compared with the number in control ponds. Dose variation in urea and cow dung also
resulted in larva count variation. Accordingly, more larvae were collected from 10 gm urea-treated ponds than 5gm and
15gm treated ones. On the other hand, ponds treated with 300gm cow dung carried higher number of larvae compared to
600gm and 900gm treated ponds.
Conclusion: The current flourishing irrigated agricultural system coupled with the extensive usage of fertilizers in all agroecological zones of Ethiopia may create suitable environmental conditions for the breeding of different mosquito species.