Morphological and Molecular Diagnosis of Fungi Causing Root Rot and Death of Date Palm Offshoots in Karbala

The study aimed to isolate and identify the fungi causing root rot and death of date palm offshoots (Phoenix dactylifera L.) in orchards of the Al-Husseiniya area in Karbala Governorate, based on morphological and molecular diagnosis, with evaluation of their pathogenicity on radish seeds and palm seedlings. The field survey included 12 orchards, and its results showed a clear spread of the disease condition, as the deterioration percentages ranged between 14–28% and the death percentages between 13–42%, indicating the presence of influential pathological causes in the success of offshoot cultivation. Laboratory isolation resulted in the diagnosis of four fungi: Alternaria alternata, Fusarium graminearum, Pythium aphanidermatum, and Rhizoctonia solani, where the fungus A. alternata recorded the highest frequency and the most severe pathogenic effect, causing a significant decrease in the germination percentages of radish seeds and palm seedlings to 15–17%. The molecular diagnosis of the most pathogenic isolate was confirmed using amplification of the ITS region and the Actin gene, and the genetic comparison via the GenBank database showed a high match with global isolates. The A. ‎alternata sequence was deposited under the number PV803540, and the phylogenetic tree showed a ‎clear evolutionary convergence with internationally registered isolates. The results indicate that ‎the severity of fungal infection is a major factor in the deterioration and death of date palms offshoots in ‎the region, and highlight the importance of early diagnosis and the application of integrated ‎management programs based on preventive agricultural practices to reduce losses and improve ‎the sustainability of production.‎