Soil nematode communities associated with hazelnut orchards in Turkey

Abstract

The study was conducted to investigate the status of soil nematode communities in hazelnut orchards in Ordu province, Turkey. Nematodes were identified to genus level and allocated to trophic groups. A total of 50 taxa were found from hazelnut growing areas including 19 plant parasites, 12 bacterivorous, 4 fungivorous, 4 predators and 11 omnivorous. Genera Tylenchus (94.5%), Gracilacus (79.1%) and Helicotylenchus (56.4%) as plant parasites, Acrobeloides (68%) as bacterivores and Aphelenchoides (68.2%) as fungivorous were widespread and found in all districts. The highest abundance of plant parasites was in Kabataş (277 individual/ 100 cm 3 soil) followed by Gölköy (196.6 ind./ 100 cm 3 soil) district. Criconemella, Meloidogyne, Paratylenchus and Pratylenchus were found as important genera by means of the damage potantial on hazelnut as plant parasitic group. The other trophic groups were at desirable level for an healthy soil system.

Description of Paratylenchus (Gracilacus) straeleni (De Coninck, 1931) Oostenbrink, 1960 (Nematoda: Criconematoidea, Tylenchulidae) from hazelnut in Turkey and its comparison with other world populations

“…Hazelnut (Corylus avellana L.) is a main perennial crop in Turkey and the country is fi rst-ranked in worldwide hazelnut production and exportation (Akyazi et al 2014). Ordu is the top province among the provinces producing hazelnut in Turkey but nematode fauna in hazelnut orchards is only partially known.…”

“…Kepenekci (2002) reported plant parasitic species from the soil and root samples of hazelnut in the West Black Sea region of Turkey without fi nding any species of the genus Paratylenchus. Akyazi et al (2014) surveyed 110 hazelnut orchards for nematode assemblages and found representatives of both subgenera, Paratylenchus and Gracilacus. Paratylenchus straeleni was described from moss and soil from Baraque Michel, Liége, Belgium.…”