Occurrence of Some Fungal Diseases on Date Palm Trees in Upper Egypt and its Control

Abstract

In 2007, date palm trees surveyed for different symptoms on leaves and fruits in Upper Egypt. The samples were collected from symptomatic rachis, fronds and fruits in four localities (El-Minia, Assiut, Sohag and Qena Governorates). The major diseases noticed were leaf spots, off-shoot decline, black scorch, leaf basal rot and fruit spots. Seven different fungal species were isolated from date palm exhibited different symptoms. The results of pathogenicity test proved the ability of Thielaviopsis paradoxa, Alternaria alternate and Negrospora oryza to infect date palm rachis, fronts and fruits, respectively. Helminthosporium sp. and Epicocum nigrum were associated with the leaf spots. E. nigrum was associated with off-shoot decline, black scorch and leaf basal rot, while Fusarium proliferatum and Aspergilus niger were associated with fruit spots. Antagonistic effect of E. nigrum against A. alternate and T. paradoxa was examined by dual culture technique which leads to clear inhibition zone. Calcium chloride (CaCl2) and E. nigrum filtrates effectively controlled the leaf spot (as major disease) when applied at suitable time (when disease severity was low).