Effect of climate and aspect on the population dynamics of the olive scale (Parlatoria oleae: Hemiptera, Diaspididae) under arid conditions [Effet du climat et de lexposition sur la dynamique des populations de la cochenille violette, Parlatoria oleae Colvée (Hemiptera: Diaspididae), en conditions arides]
Chafaa S.,University of Batna |
Biche M.,Ecole Nationale Superieure Agronomique El Harrach |
Chenchouni H.,University of Tebessa |
Sellami M.,Ecole Nationale Superieure Agronomique El Harrach |
Si Bachir A.,University of Batna
Annales de la Societe Entomologique de France | Year: 2013
This work aims to study some bio-ecological aspects of the olive scale Parlatoria oleae: Colvee 1880, bio-aggressor of olive cultures in arid area. The monitoring of biological cycle and the demo-ecology of this pest have been achieved through periodic population counts on different parts of the tree (method of Vasseur and Schvester) from December 2010 to December 2011 in the region of Ain Touta (north-eastern Algeria). In the region of study, the species had two generations a year: a spring generation that occurred from April to July and a fall generation that evolved from August to October. Egg laying began in April and lasted until the end of September. The most favourable exposition for this insect was North. Egg laying average was 8 to 9 eggs per female. Statistical analysis showed that the effects of the studied climatic conditions (minimum, maximum and average temperatures, precipitation, frost and De Martone's aridity index) on population size during the different stages were very variable. The number of individuals showed statistically highly significant variations according to the exposition on the trees. 2013 © Société entomologique de France.