Archive \ Volume.7 2018 Issue 2

Annual and Stationary Variation of Black Rat Rattus Rattus (Linnaeus, 1758) Damage On Date Palm Inflorescences in Southeastern Algeria

Zeïd Alia , Djilani Ghemam Amara , Ahmed Elkhalifa Chemsa , Amar Eddoud , Karim Souttou , Makhlouf Sekour

The estimated damages caused by Rattus rattus on Phoenix dactylifera (L. 1753) involved 25 sites distributed equally over 5 stations in the Souf region (south-east of Algeria). The first traces of the damages could be summed up in a deterioration of the inflorescences (spathes) before and after their openings. However, a five-year follow-up (from 2012 to 2016) revealed that 2014 (63.7±8.0 %) was the year with the highest loss rates ranging from 51.4 % to 81.2 %. On the other hand, the lowest rates were recorded in 2016 (20.5±5.4 %) with values varying between 9.5 % and 21.9 %. Depending on the stations, the highest attacks were observed in station 5 with 39.7±16.6%. On the other hand, the lowest rates were recorded in station 3 with 23.1±11.3%. Regarding the evolution of attacks, open inflorescences (29.7±19.9%) were relatively more attacked than the closed inflorescences (20.4±14.9%).