Ecological studies of california red scale, Aonidiella aurantii (Hemiptera : Diaspididae)‎ infested citrus sinensis in Giza governorate

Abstract EN

The California red scale, Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae) is considered a key pest of citrus that has spread during the last decades up to cover a vast extension of agricultural landscapes.

It was detected in Citrus sinensis var.

balady of a private orchard located at El-Saff, area, Giza Governorate.

During two years 2014 and 2015, A.

aurantii population dynamics and seasonal trends were studied on this Citrus variety.

The results indicated that, population of A.

aurantii recorded three activity peaks of abundance and three overlaping generations/year.

In the first year of study three peaks of infestation were recorded in midMay, mid-August and October first, while in the second year, these peaks were observed during May first, August first and October first.

The first generation of first year started from February first till the mid- May.

The second generation was extended from mid-May till the mid-August, third generation was indicated on mid -August till the mid- December.

A.

aurantii showed the same trend with the second year and had three generations.

The duration of the first one was extended from mid-January to May first and the second generation lasted from May first to August first, while the third generation from August first till mid-December.

The calculated infestation rates of A.

aurantii were high in summer, spring and autumn months, whereas, relatively low rate of infestation were recorded with winter months in both years.

There was positive significant relationship between metrological factors and the total population of A.

aurantii and a simultaneous occurrence of the total population of A.

aurantii, while relative humidity relations was negative in first season and positive in the second season but insignificant in both