Population Fluctuation and Control of the Citrus Rust Mite , Phyllocoptruta Olievora ( Ashmead ) ( Arachnida : Prostigmata : Eriophyidae )

Abstract

Studies on the population fluctuation and control of the citrus rust mite Phyllocoptruta olievora were carried out on Washington Navel Orange trees in Nubaria, Bohaira, Egypt an important citrus producing area during 2013. The results showed that the citrus rust mite was present on Orange trees throughout the year. The lowest population occurs in December, January and February. Later the population was slowly and gradually increased until June. The period of maximum infestation usually occurs during late July or August or even September. Three annual peaks of seasonal abundance were observed. The first peak occurred in late June being 28.4 and 35.2 individuals per leaf and fruit respectively when temperature and relative humidity averaged 31.5°C & 48.12%. The second peak in late July being 35.5 and 42.9 individuals per leaf and fruit when temperature and relative humidity averaged 30.13°C &58.30%. The third peak, which was the highest, happened in mid-August being 48.6 and 70.5 individuals per leaf and fruit, when temperature and relative humidity averaged 32.16°C & 60.58%. Five acaricides: Abamectin, Challenger, Ortus, Antimite and Sulphur were selected to control P. olievora and their side effects on the predatory mite, Amblyseius swirskii Athias-Henriot. The results indicated that the selected acaricides caused a reduction percentage of the mite population ranged from (73.33-95.12% and (75.30-94.66%) when used on leaves and fruits respectively. The selected acaricides displayed different side effects on the predatory ite where abamactin was the less harmful with a reduction percentage of 12.5% while Ortus was the most harmful with a reduction percentage of 33.33%.