Hassan, A.S., Hammad, K.A.A., Shahem, A.A., & Nabil, H.A. 2008 The equilibrium point between Hemiberlesia lataniae (Signoret) and its two associated parasitoids under field conditions on guava trees.. Proceedings of the XI International Symposium on Scale Insect Studies, Oeiras, Portugal, 24-27 September 2007. ISA Press Lisbon, Portugal 322 pp.

Notes: Studies were carried out on guava tress (Psidium guajava L.) at Kafer Saker district, Sharkia Governorate, Egypt, in three successive years (1999, 2000 and 2001) to determine the equilibrium point between Hemiberlesia lataniae (Signoret) and its associated parasitoids Aphytis sp. and Aspidiotiphagus sp. (Hymenoptera: Aphelinidae) under field conditions. The point at which the increase of parasitoids numbers leads to the decrease in the insect pest (the equilibrium point) was calculated and gave means of 0.806 parasitoid/ insect in 1999, 0.280 in 2000 and 0.863 in 2001. The mean of these equilibrium points was 0.65 parasitoid scale insect.