Occurrence, identification, and diversity of parasitic nematodes in apple (<i>Malus domestica</i> Borkh.) orchards in the Central Anatolia Region of Turkiye

Root lesion nematodes (RLNs) (Pratylenchus spp.) are one of the most economically important plant parasitic nematodes (PPNs) and are considered one of the leading causative agents of apple diseases that severely decrease yield and quality in apple (Malus domestica Borkh.) orchards. Occurrence, identification, and diversity of PPNs in apple orchards in central Anatolia region of Turkiye have not been well understood. Therefore, in this study, a field survey was conducted in this region to reveal the occurrence, distribution, and diversity of mainly RLNs. The primary analysis of soil and root samples based on morphology revealed that 8 PPN species were present in sampled areas, the most prevalent of which was RLNs. As a result of morphological, morphometric, and molecular studies, a total of 5 species of RLNs [Pratylenchus crenatus Loof, 1960; Pratylenchus neglectus (Rensch, 1924) Filipjev & Schuurmans-Stekhoven, 1941; Pratylenchus penetrans (Cobb, 1917) Filipjev & Schuurmans-Stekhoven, 1941; Pratylenchus thornei Sher & Allen, 1953 and Pratylenchus vulnus Allen & Jensen, 1951] were identified. Phylogenetic analysis with the D2-D3 domain of LSU-rDNA sequences further confirmed the identification. The results indicated that P. thornei was the predominant species in surveyed areas, followed by P. neglectus. The results confirmed the host status of apples for RLNs and demonstrated that RLNs were the most threatening PPNs in the surveyed apple orchards. The necessity of determining the damage caused by plant parasitic nematodes to apple production emerges as an important factor to be done as a future study.