NEMATOLOGY, cilt.14, ss.839-854, 2012 (SCI-Expanded)
The distribution of important plant-parasitic and free-living nematodes in the cereal production areas of the Central
Anatolian Plateau (CAP) of Turkey was investigated with systematic surveys. Two important plant-parasitic nematode groups were
found widely distributed; cereal-cyst nematodes (78.3%) and root-lesion nematodes (42.6%). Cereal cyst nematodes (CCN) were
identified as
Heterodera filipjevi in 18 provinces. Heterodera latipons was found in only one province. Pratylenchus thornei and P.
neglectus
were the most widely distributed species of root-lesion nematodes. Other frequently recorded plant-parasitic nematodes
belonged to the genera
Geocenamus (52.4%), Pratylenchoides (35.6%), Helicotylenchus (29.7%) and Paratylenchus (19.2%). Konya
on the southern CAP had a significantly high incidence of
P. neglectus as well as free-living nematodes. The incidence of CCN was
greatest in areas of sandy soils on the CAP, with densities of up to 95 cysts (100 g soil)
−1. Population densities of Geocenamus,
Pratylenchus
and Pratylenchoides were high in some locations. Soil physicochemical properties were investigated for their relationship
to nematode distribution. There was a slight positive correlation of
P. thornei and clay content; conversely, there was a significant
negative correlation of
P. neglectus with clay and a positive correlation with sand. Electrical conductivity (EC) was positively correlated
with
P. neglectus. Nematodes in the genera Helicotylenchus, Paratylenchus, Trophurus and Tylenchorhynchus were only recorded at low
population densities in the sampled area. By contrast, nematodes in the genera
Aphelenchus, Aphelenchoides, Ditylenchus, Dorylaimus,
Tylenchus
and bacterivorous genera had relatively high populations. Total free-living nematodes were positively correlated with EC and
zinc (Zn) concentration. The Zn content of soil was generally at a level deficient for plant growth.
Keywords –
barley, electrical conductivity, Heterodera filipjevi, Heterodera latipons, iron, nematode survey, organic matter, pH,
Pratylenchus
spp., texture, wheat, zinc.