ECOLOGICAL STUDIES ON THE SCALE INSECjT PULVINARIA PSIDII (MASK) INFESTING COFFEE TREES (COFFEA ARABICA) AT QALUOIYA GOVERNORATE, EGYPT.

EcOlogical aspects of Pu/Vinaria psidii attacking coffee trees (Coffeae
arabica) in Qaluobiya Governorate in Egypt was sludied during the two success ve
season of 2000/2001 and 2001 12002 .
The obtained results denoted all stages of P. psidii succeeded to settled on
coffee trees and expoded aU over the year.
Atso. data gathered during first year of study fOf population density was
detected four distlnC1 peaks and three annual peaks. In the second year. Also,
ecological data showed thai:                                                                              I

During the first and second years P. psidii had three overlapping generations.

Also, results proved that there were positive correlation between maxi urn
temperature and 1" & 3rd generation while there was a negative correlation wilh the



    2"" generation.                                                     .

Minimum temperature had positive corralation with ," generation but it appeared
negative correlation with the 3·^J generation. The data proved a negalive correl~tion
between R.H. % with aU annual generations except second generJlion of the first
year.