SUSCEPTIBILITY OF SELECTED DATE PALM CULTIVARS TO Parlatoria blanchardi INFESTATION IN SAUDI ARABIA

The current study examined the response of date palm cultivars in the Al-Qassim region of Saudi Arabia to infestation by the date palm scale insect, Parlatoria blanchardi (Targioni Tozzetti) (Hemiptera: Diaspididae), over two consecutive years (2021/2022 and 2022/2023). In addition, we evaluated the relationship between the total number of P. blanchardi individuals and the concentration of essential nutrients in date palm leaflets. The findings demonstrated that P. blanchardi populations were present throughout the year across all palm cultivars. The sensitivities of these cultivars to P. blanchardi were as follows: the Rashodia cultivar was categorized as highly susceptible to infestation because it had the highest number of pests; Red Sukary and Shakrah cultivars were found to be susceptible; Barhi was found to be relatively resistant in both years; the Nabtet Ali cultivar was moderately resistant during the first year and susceptible to infestation during the second year; while the Sajae cultivar exhibited the lowest number of P. blanchardi in both years, and was relatively resistant to pests. Over the two years, P. blanchardi numbers were adversely associated with the potassium content of date palm cultivars and positively correlated with nitrogen and phosphorus concentrations. According to principal component analysis, six date palm cultivars were significantly affected by P. blanchardi number.