Occurrence and abundance of nematodes in almond growing areas in Karaman, Türkiye and their relationships with almond characteristics

Almond, Prunus dulcis Rouchy (Rosales: Rosaceae) is an economically important plant species widely grown in Türkiye. Plant parasitic nematodes have been known to affect the economical production of almond. In this study, the occurrence and abundance of plant parasitic and free-living nematodes were determined in almond-growing areas in Karaman province in 2024. The soil samples were collected from 40 almond orchards and two wild almond production areas. Each orchard was represented by 20 subsamples collected in a zigzag pattern with 20-25 footsteps in between using a 2.5 cm diameter soil corer from the projection area of the trees. The nematodes were extracted from soil samples using petri dish technique for 72 hours. The most prevalent plant parasitic nematodes were Ditylenchus spp. Filipjev, 1936 (Rhabditida: Anguinidae) (97.6%), Tylenchus spp. Bastian, 1865 (Rhabditida: Tylenchidae) (88.1%) and Pratylenchus spp. Filipjev, 1936 (Rhabditida: Pratylenchidae) (83.3%). The populations of most prevalent nematode species Ditylenchus spp. and Pratylenchus spp. ranged between 0-143.9 and 0-197.4 nematodes per 100 g dry soil, respectively. The population of bacterivorous nematode Cephalobus spp. Bastian, 1865 (Rhabditida: Cephalobidae) was positively correlated with 10-year-old, seed rootstocks almonds cultivated under rainfed conditions.