No abstract

The objective of this study is a morphometric characterization of local goats in western of Algeria. With the use of 19 quantitative variables, we carried out a discriminant analysis on 119 goats and 32 bucks divided into 4 Wilayas (Tlemcen, Adrar, Naama and Bechar). The discriminant analysis on males was not significant. As for the female population, the analysis of variance (ANOVA) on the region effect was highly significant p=1.32 x 10-11. A clear separation has been found between the populations, with the exception of Naama and Tlemcen, which are overlapped. Measurements belonging to chest width ( LP),chest circumference ( TP), chest depth ( PP), rump width (LB), ischium width (LI), withers height( HG), ear length LO) and hair length (LPI).are the best variables that separate between regions in the female population, with a very high significance level (p<0.01). The area under the ROC curve (AUC) is 82.04%. This study can serve as a basis for more precise genetic characterization studies of this species.

No abstract

In Mazagran, Mostaganem Province, Algeria, the seasonal variation in abundance of the scale insects (Hemiptera: Coccomorpha) Coccus hesperidum LINNAEUS, 1758 (Coccidae) and Icerya purchasi MASKELL, 1879 (Monophlebidae) was studied in an orchard on two host plant species, orange (Citrus sinensis) and lemon (C. limon) between December 2018 and November 2019. Every ten days, samples of leaves were collected for monitoring insect numbers. In C. hesperidum on orange and lemon trees respectively, there were three or four population peaks annually (P<0.0001). In I. purchasi, there were three generations annually (P<0.0001). In both scale insect species their abundance was correlated with temperature (P<0.0001 for C. hesperidum, and P=0.010 for I. purchasi) but not with relative humidity levels. Lemon trees had the higher scale insect abundance on 50% of days sampled, for both C. hesperidum and I. purchasi (P<0.005), whereas orange had lower numbers of both scale species. C. hesperidum and I. purchasi occurred on all three sample plots; numbers of both species (particularly C. hesperidum) showed a positive relationship with wind speed (P<0.0001 and P=0.002, respectively), as strong winds probably picked up and carried crawlers into the sample plots situated downwind.

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.