Alternaria phoenicis sp. nov. and Alternaria ouedrighensis sp. nov. (Pleosporales, Pleosporaceae): Two new species associated with leaf spot and blight diseases of date palm (Phoenix dactylifera L.)

Date palm (<i>Phoenixdactylifera</i> L.) is one of the oldest fruit crops grown in the semi-arid and arid regions, playing significant ecological, environmental and socio-economic roles. Recently, palm leaf spot and blight diseases have indeed emerged as significant threats to phoeniciculture. They reduce yield and quality of dates leading to economic losses. Therefore, a survey was conducted in four palm groves located in the Biskra and Ghardaia provinces of Algeria. This investigation revealed two new <i>Alternaria</i> species associated with leaf spot and blight symptoms on date palm. These newly identified species are designated as <i>A.phoenicis</i> <b>sp. nov.</b> and <i>A.ouedrighensis</i> <b>sp. nov.</b>, which belong to the <i>Ulocladioides</i> and <i>Embellisia</i> sections, respectively. The isolates were phylogenetically identified using the key genetic markers of the genus including the large subunit ribosomal DNA (LSU), internal transcribed spacer region of the ribosomal RNA (ITS), glyceraldehyde-3-phosphate dehydrogenase (<i>GAPDH</i>), RNA polymerase II subunit (<i>RPB2</i>), translation elongation factor (<i>TEF1</i>) and plasma membrane (<i>ATPase</i>) genes and illustrated based on the morphological characteristics.