Identification of Different Fungal Fruit Rot Pathogens of Date Palm (Phoenix dactylifera L.) using ITS and RAPD Markers.

Abstract

The fungal diseases of date palm (Phoenix dactylifera L.) are one of the most serious pathogens attacking different parts of date palm trees and causing significant reduction in date palm growth; development and production. Recently, the infection of date palm fruit with rot disease in Basra province/ Iraq is raising concern for the workers in dates production. The goal of present study was to isolate and identify these pathogens using molecular approaches. Four genera were isolated from infected Barhee cv fruits which were: Alternaria; Cladosporium, Epicoccum and Ulocladium, most abundantly genus was Alernaria (35%), followed by Cladosporium (25%). The high virulence affects of these pathogens were approved at laboratory on dates fruits. Molecular identification using internal transcribed spacer primers (ITS1 and ITS2) were performed, ITS DNA sequences of each examined fungi were applied into BLAST (NCBI) and the species identities were proven as A. tenuissima; C. herbarum; E. sorghinu, and U. atrum. Further, five different RAPD markers were applied to show the genetic variation among these pathogens, results showed that dendrogram cluster analysis elucidated a genetic distance of 83-94% among fungal species, which separated into different clusters. Additionally, the observations of extracellular enzyme activity of examined fungi were followed, results showed a good activity of both cellulase and protease enzymes, but no lipase activity was observed with all tested fungi.