THE INFLUENCE OF THE REGION AND THE HOST PLANT ON POPULATION DYNAMICS OF PARLATORIA ZIZIPHI (LUCAS) (HEMIPTERA: DIASPIDIDAE) IN MITIDJA (ALGERIA).Khaoula Aroua, Mehmet Bora Kaydan, Tange Denis Achiri and Mohammed Biche
The aim of this work is to study the influence of the regions and the host plants on some bioecological aspects of the black parlatoria scale, Parlatoria ziziphi (Lucas) (Hemiptera: Diaspididae). The monitoring of the biological cycle of this pest was made by periodic counting of the populations on different part of the tree such as branches and leaves from January to December 2017 in the region of Rouiba [36Â° 432 N 3Â°162 E] and in the region of Oued El Alleug [36Â°332 N 2Â°472 E]. The scale insect, had three generations in a year on Clementine and orange trees (Citrus orange, Washington Navel) which corresponded with the three sap thrust on spring, summer, and the autumn. The three periods of activity and laying in Oued El Alleug Region started earlier compared to Rouiba Region. The average egg laid varied from 8.44 to 10.02 eggs per female on the Clementine tree and from 6.98 to 7.93 eggs per female on the orange tree. For each season, the crawlers migrated to the places that offer them favorable conditions. The analysis of the varieties showed that the workforces and the fecundity were influenced by date, variety and region. The distribution of the active larvae of the black Parlatoria scale was statistically significantly (P= 0.05) affected by the different cardinal directions of the plants in different seasons. The findings of this study have huge implications for Parlatoria scale insect control.