SOME BIOLOGICAL ACTIVITIES, FIELD OBSERVATIONS AND DETERMINATION OF DAMAGE OF EUCALYPTUS STEM BORER, PHORACANTHA SEMIPUNCTATA F.

Follow-up of biological activities of eucayptus stern borer. Phora­cantha somipunclata F. (Colecotora:Cerambyddard showed that pre. oviposition, oviposibon. post-oviposition and Incubation periods recorded 2.25 (1-5) . 6.45 (2-12) . 405 (2-10) and 9.3 (6-13) days, respective­ly. Durations of pre-pupa and pupa listed 9.5 (3-17) and 15.65 (12-19) days. respectively. The number of pupal chambers and emerged beetles mother female were 22.8 (8-38) eharnbOrs and 19 (7-32) beetles. re­specttvety. Adult hardness recorded 6.55 (4-9) days, the female Wool 13.7 (4.25) days. while the mat r lived 11.25 (419) days. The female laid 42.7(1241) eggs, the percentage of egg death was 21.8 % (6.1­37.5 %). Field observations revealed that attack density represented by number of egg batches varied from 4 to 11 batches per eucalyptus log ( 45- I lOcm.long).The number of eggs 1 batch was 24.48 (6-68) eggs. Hatching percentage (75.71%) differed from 50 % to 93.9 %. Larval densIty(428.03 larvae An²) resulted 68.36 %death in number of hatch­ing larvae. 280 full grown larvae (135.42 pupal chamber /m² ), 217 emerged beetles (104.95 adult /m² & 22.5 % death in pupae) and 75.48 % reduction In the broods. Three pedods ci emergence were ob­served horn stored infested logs during Juno 1999 to June 2000, the first was alter 18 weeks during 3rd week of October to 2nd week of No­vember (21.06 % emergence), the second occurred after 30 weeks dur­ing 3rd week of January to 3rd week of February (73.68% emergence) and the third was noticed after 48 weeks during 1st week of Juno (5.26 % emergence). The estimated damage of lost wood volume average 263.06cm' / maturity terra or pupal chamber and each one female can be destroyed about 5998.22 cm³ (average) from attacked wood by her brood.