LAUSR

Meloidogyne chitwoodi Golden, O’Bannon, Santo & Finley, 1980 and M. hapla Chitwood, 1949 are important pests of potato in Turkey. This study was conducted in three experimental areas where conventional agronomic practices have been done in Nigde (Center district) and Nevsehir (Center and Derinkuyu districts) provinces. Nematodes were extracted by modified Oostenbrink dish from soil samples taken from 0 to 30 cm depths every month between 2014 and 2017 to assess the population fluctuations of these root-knot nematodes under field conditions. The whole suspension was checked for Meloidogyne juveniles which were counted under an inverted microscope. Morphological and molecular identification results showed that two experimental areas were infested by M. chitwoodi while one experimental area (Derinkuyu) was infested with both M. chitwoodi and M. hapla. Our study showed that M. chitwoodi population level decreased during wheat cultivation and were maintained under rye cultivation, whereas M. chitwoodi and M. hapla population levels increased rapidly under potato and bean cultivation. It was found that M. chitwoodi population increased more when potatoes were planted, while M. hapla increased more in bean. The best sampling time for M. chitwoodi and M. hapla was observed to be right after harvest, when the population was highest, but both could be detected in soil samples even when the ambient temperature was below zero. These results demonstrated that farmers should be careful in their choice of rotational crop with potatoes in areas infested with M. chitwoodi and M. hapla.