Population Fluctuations of Hemiberlesia lataniae (Signoret) and Survey of Its Natural Enemies in Qaliobiya Governorate.

Document Type : Original Article

Authors

1 Scale Insect and Mealy bug Research Department, Plant Protection Research Institute, Dokki, Giza, Egypt

2 Physiology department, Faculty of Agriculture Cairo University, Giza, Egypt

Abstract

The population fluctuation of the latania scale, Hemiberlisis lataniae (Signoret) was studied for two successive years from (early December, 2012 till mid November, 2014) on guava trees that was obligated to produce its yield in winter to avoid infestation by fruit fly and low price at Shebeen El-Qanater district, Qaliobiya Governorate. The obtained results revealed that H.latania occurred on guava tree all the year round and has three overlapping generations a year. The first generation lasted 120, days (autamn generation), the second generation lasted 90 days, (winter generation) and the third generation (spring generation). It lasted 90 days during the first year. Also the three generation of the second year of investigation were occurred in the same periods where the trees were vigor and full of plant juice (production of green shoots, flowering and fruiting periods). The relationship between the pest fluctuation and three climatic factors (minimum and maximum temperature & R.H. %) were studied where the simple correlation of the Max. and Min temperature were negative and significant but R.H. % gave negative and insignificant. These results is abnormal because the most effective factor is the leaf age in third degree. the combined effect was positive and significant. Also the natural enemies (predators and parasitoids) was surveyed and identified. The surveyed predators were five species of predaceous mites with high, moderate populations and Chrysoperla carnea (stephens), Rodolia cardinalis (mulsant) with low population. Also there were three different parasitoids associated with the scale insect, H. lataniae, Aphytis sp, Comperiella bifasciata Howard (primary parasitoids) and Mariettja vensis (Haward) (hyper parasitoid).

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