Boufaroua (Oligonychus afrasiaticus) in Tolga palm groves in 2021

Abstract

Global warming, which has affected the entire globe, has increased the activity of crop pests. The Boufaroua (Oligonychus afrasiaticus) is among the serious threats to date production in Algeria. Through regular monitoring, field surveys and recording of temperature and relative humidity data within the Tolga palm grove (known for the famous 'Deglet Nour' date), it was found that the spider of this date palm in 2021 has expanded in the study area. This spider, in addition to half-soft cultivars, has exceptionally attacked soft and dry cultivars during this year. The multiplication of this tiny spider increases when the average air temperatures follow an upward trend (above 30 °C) and the relative air humidity registers a perpetual decrease (below 35 %); two important waves of Boufaroua propagation were recorded, the first one during the second dekad of June and the second one at the beginning of August. Farmers in the study area did not apply preventive control of Oligonychus afrasiaticus and resorted to curative control, when the pest appeared; where chemical treatments were most frequent. Nevertheless, a part of the farmers uses inherited (traditional) practices, while a minority uses household detergents.