FACTORS INFLUENCING FLY DEVELOPMENT | MARTINS LIBRARY

·                     Temperature, Humidity and Light

            Generally, the period of development for each stage decreases as the temperature rises. At  24⁰c , the eggs of M. domestica requires 17hrs before hatching whereas at 37 ⁰C  the period was 7.6 hrs (Davidson, 1994). This is compared to the eggs of M.D.vicina hatched in 6 hours at 35-38⁰c and in 11 hrs at 25-30⁰c (Hafez, 1941). Adult M .domestica are active from 7⁰-43⁰C with the optimum at 33-33.5⁰C (Nieschulz, 1935). At 15.5⁰C, adults survived up to 91 days (Dove, 1916). The effect of humidity is usually combined with temperature. However, excessive moisture is detrimental to larval development. The significance of light in rearing procedures for M .domestica appears minor, but

with M .autumnalis strong artificial light or sunlight is necessary for Oviposition (Fales, 1963).

·                     Crowding

            Too many larvae for a given supply of food results increased larval mortality and smaller adults. Adult crowding causes excessive activity, competition, decreased longevity, and greater mortality. An increase in the diameter of the rearing container from 4cm-7-10cm resulted in the period between Oviposition and the emergence of female M.D.vicina declining from 17.3-13.1 to 12.0 days (Nagasawa and kishino,1959).

·                     Biological State

The age of the female at the time a batch of eggs is laid influences the percentage hatched and the longevity of adults in succeeding generations (Meister, 1962). Any selection of a developmental stage on a continuous basis will eventually segregated certain characteristics that could enhance or handicap the survival and propagation of the species.

·                     QUALITY OF FOOD

            The addition of small amount of vitamin A, thiamin, riboflavin, panthenic acid, pyridoxine and RNA to fly media was not beneficial, but at high dosages they were harmful (Sawicki and Holbrook, 1961).cholesterol also had no effect on M. domestica has been reared on a synthetic medium (Monroe, 1962) and the weight of larva, pupa and adult approached those of flies by CSMA method. Acidity (Meister, 1962) amount of yeast and ratio of water to media (Hirakoso, 1962) influence production.