INVESTIGATION AND MOLECULAR IDENTIFICATION OF CUCUMBER DAMPING-OFF FUNGI UNDER GREENHOUSE CONDITION

Abstract

A disease survey was done from the cucumber greenhouses in four locations (Qushtapa, Tandura, Daraban, and Choman) of Erbil province from July to October (2021) were obtained; the highest disease incidence was recorded in Daraban 57.44%, Tandura 45.76%, Qushtapa 21.88%, and the lowest disease incidence were recorded in Choman 18.3%. Different damping off fungi Isolated from soil, seeds, roots, and stem samples of cucumber plants. In all samples were isolated, Pythium aphanidermatum, Globiporangium ultimum, Phytophthora parasitica, Phytophthora melonis, Fusarium solani, and  Rhizoctonia solani and identified confirmed molecularly, in all isolates Rhizoctonia solani is the most virulent fungus with 110 isolates, Fusarium equiseti 99 isolates, Globiporangium ultimum 90 isolates, Fusarium solani 88 isolates, Pythium aphanidermatum 63 isolates, Phytophthora melonis 61 isolates, and the lowest isolates was Phytophthora parasitica 46 isolates. Also isolated important bio-agent Trichoderma citrinoviride. Five isolated fungi were the first recorded in Iraq that isolated in cucumber seedlings caused damping-off, there are Globiporangium ultimum (Accession Numbers OP235917), Fusarium equiseti (Accession Numbers ON665765), Phytophthora parasitica (Accession Numbers ON665761), Phytophthora melonis (Accession Numbers ON665763), and Trichoderma citrinoviride (Accession Numbers ON665764).

Keywords

• cucumber
• damping-off fungi
• molecular identification