Polymer Research Unit , College of Science Al-Mustansiriya University

Abstract

           This study is performed at the gardens of  the  Agriculture College / Baghdad University, from March to August 2016. The aim is  study to create  the  life tables of  the mealy bug Phenacoccus solenopsis, the high density is  in May. It reveals  that the primate  mortality factors  play  a key part  in the  pest population density, these life table expose  that the eggs infertility  give rise to  mortality rate,  then  the photoperiodism and sex ratio, play  the main  role in the hesitation  of the high pest density .The limited effect by biotic factors is on the larvae  stages. though , the significance  of these vital  and not vital  factors  in the population density regularity, below the economic threshold  level, with  carry on  the trend index,  to high values in the highest levels direction up to 1.7-1.34, on the cotton rose Hibiscus mutabilis  ( Malvaceae). The results showed  that the photoperiodism and the adult mortality were the responsible factors in decreasing  the high insect density  . And the trend index during the interval  from March to August 2016, was 1.07, 1.03, 0.93, 0.88,0.30 and 1.34, in Baghdad respectively. so, it has become meaningful  to decrease the insect^,s natural enemies of  from original regions necessary for pest management and decrease  the widespread  of the high insect density.

Keywords: photoperiodism, trend index, adult mortality,