Morphometric characterization of the pine processionary, Thaumetopoea pityocampa in the Tlemcen area, Algeria

The pine processionary (Thaumetopoea pityocampa) is the most important defoliator of coniferous forest of the Mediterranean basin. The pine processionary also caused real public health problems. The urticat property is the origin of its health problems. It is still the subject of several studies to this day in order to develop friendly control strategies that respect the environment. The study carried out about the characterization of the pine processionary populations in two stations of pine forests located at the area of the Tlemcen. The caterpillars were collected in January 2016 in the Tlemcen region. Measurements were performed on L5 larvae and male and female nymphs. The statistical analyses were carried out using the SAS 9 software. The results obtained show that the females have an average length of 11.51 ± 1.07 mm and an average width of 7.87 ± 0.33 mm. Males have an average length and width of 11.51 ± 1.07 mm and 6.48 ± 0.29 mm, respectively. The length and width of the head capsule is 43.28 ± 6.63 mm and 4.50 ± 1.35 mm respectively. The GLM procedure of the SAS.9 software allowed us to observe that the Sebdou station is more attacked by this insect compared to the Ghazaouet station despite that there is a similarity between the biometric characters of the pine plants. Our statistical analyses have also shown that trees with the longest needles are the most resistant against   insect attack.