THE ANNUAL PRESENCE AND THE AGE SPISIFIC FECUNDITY LIFE TABLE FOR CoccinellaundecimpunctctaL IN BAGHDAD
journal of kerbala university,
2013, Volume 9, Issue 2, Pages 256-263
AbstractThe annual presence were studied for the adults of “Coccinellaundecimpunctata L” for a full year in a field of Alfa Alfa var. Hairy pervian and it was done by making 100 sweep weekly by insects standard net mesh. The results obtained indicates that the adult ladybirds are found on the plants throughout the whole year but with fluctuated population, with very low densities when thereare high temperatures and lack of preys in the hot summer days; to reach 10 adults/ 100 sweep in the first week of July and continued to decline until it reached the 1 adult/100 sweep in the fourth week of July and continued its decline during the month of August until the last week of September, where mild temperatures and humidity begin to appear, low densities population of adults were recorded from the last week of September last week of December and then it began increasing gradually during the months of February and March and continued During the month of April, where mild temperatures and relative humidity and frequent prey were recorded, especially from alfalfa trout “Therioaphis maculate” and fabaebeans “Acrythosiphonpisum” where there were quick increasing in the population density peaked in the mid-March (36 adults / 100 sweep) then began to decline gradually up to 12 adults / 100 sweep at the end of June. The results shown in the tables explainsthe susceptibility to reproduction of the adults whenit is cultured on an “Aphis fabae”at temperature of 28 ±1oC and relative humidity of 60 ± 5% ; the survival ratio of adults began to decline at the beginning of day 40, and it needs 10 days to make its first breeding, and its total age is 62 days. Each female can lay an average of 1257.24 eggs per cycle, and the value of the Net reproduction rate(R0) for one female is 410.83 Female / Female / generation, which proves that the populationis of the unstable kind, as the rate of the Intrinsic increase (rm) was 0.118 Female / Female, while the average length of generation (T) was 50.74 days.
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