Rhizosphere and Rhizoplane Mycoflora of Date Palm (Phoenix dactylifera) from Saudi Arabia

Abstract

This is the first comparative study of the rhizosphere and rhizoplane mycoflora of Phoenix dactylifera (date palm) from three different regions of Saudi Arabia. Samples of roots and  rhizosphere soil from the date palm were collected from Jeddah, Jizan and Riyadh. A total number of eighteen samples were collected. Three samples from each region were collected and screened for mycoflora during the month of May 2017. The mycoflora was aseptically cultured on Potato Dextrose Agar plates and Czapek Dox agar plates. A qualitative and quantitative assessment of mycoflora was carried out from the fungal cultures on the petri plates. Slides were identified by microscopic and macroscopic morphological characteristics. A total of 48 fungal isolates represented by 11 fungal genera were isolated from the samples belonging to the three classes of fungi i.e. Oomycotina, Zygomycotina and Ascomycotina. The rhizoplane and rhizosphere mycoflora was represented by Aspergillus Chaetomium, Cunnighamella, Fusarium, Mucor, Nigrospora, Oidiodendron, Penicillium, Phytopthora, Rhizopus and Syncephalastrum. The most predominant genera were Aspergillus followed by Rhizopus. The rhizoplane mycoflora was lesser than the rhizosphere mycoflora in Jeddah and Jizan. Riyadh recorded equal number of both rhizoplane and rhizosphere mycoflora. The fungal genera isolated are soil borne saprophytic, antagonistic or phytopathogenic fungi of the date palm. The information on the phytopathogenic mycoflora is important to plant pathologists and date growers in these regions so that they can take up necessary phytosanitary measures to prevent damage to the date crop. This study can help in controlling the diseases, damage and economic losses to the date crop.