The involvement of the vital secondary metabolites of the pathogen Alternaria alternate (Fr.) Keissl. in the occurrence and progression of Alternaria leaf spot disease in date palm (Phoenix dactylifera L.) Review Article

Abstract

Leaf spot disease is one of the most significant and pervasive date palm diseases in the Basrah region of Iraq. The symptoms appear on the leaves of the fronds and on the medial veins of the fronds of the date palm trees. Different colors and shapes of spotting symptoms depend on the causative fungus and the environmental conditions. There are several potential causes of leaf spot disease, but one of the most significant is the fungus Alternaria alternata (Fr.) Keissl. A. alternata is essentially a saprophytic, global fungus that enters epidermal cells directly due to its ability to be pathogenic. It is crucial to research how their pathogenicity has developed within the host plant. A. alternata isolates directly attack the host plants by piercing the fungal hyphae using small infection pegs that enter the susceptible host plant, such as the fronds (rachis) of date palm trees, and the infection symptoms have shown as erratic brown dots. These spots enlarge throughout this time, turning the tissue brown and possibly turning the core of the spot pale white, and in cases of severe infection, the death of leaves occurs. Alternaria alternate is a highly metabolically active fungus, and as a result, the metabolic by-products of this fungus are strongly related to plant disease. Metabolic products play a crucial role in the ability of fungi to withstand a variety of adverse environmental circumstances. From these starting points, the following review seeks to shed some light on certain specifics about the biolog