INFLUENCE OF LARVAL DIET AND POPULATION DENSITY ON PRE- ADULT DEVELOPMENTAL RATE OF LABORATORY POPULATIONS OF CULEX QUINQUEFASCIATUS (DIPTERA; CULICIDAE)

摘要

The influence of larval diet and population density on pre-adult developmental rate, adull population sizes, pre-adult survival and sex ratio was investigated. Mean developmental period varied significantly with low larval densities. Similarly, therewere significant variations of developmental periods with different diets. A comparison of the survival rate of larvae fed with the three types of diets showed significant variations (P<0.05). Sex ratio varied significantly from 1:1 ratio in adult raisedfrom larvae fed with milk powder while those raised from liver and liver/milk powder varied non significantly. Mean pre-adult developmental period of larvae fed with milk, liver and milk/liver powder were 15.55±0.76, 9.54±0.32 and 9.68±0.14 days respectively and those for densities of 30L/300ml. 60L/300ml, 150L/300ml and 300L/300ml were 10.60 ±1.36, 11.68 ±2.10, 11.70 ±2.30 and 12.39 ±2.17 days respectively. The mean pre-adult survival for larvae fed with milk, liver and milk/liver powder were 22.88±3.19%, 68.13±6.20% and 66.53±4. 75 respectively and those for densities of 30L/300ml, 601/300ml, 150L/300ml and 300L/300ml were 65.57±17.31%, 49.43±15.68%, 47.4 ± ll.39% and 47.57 +15.21% respectively. Analysis of the results showed that intra-specific competition was high for diet (food) and effect of density was greater at extreme densities.