Integrative Morphometric and Molecular Approach to Update the Impact and Distribution of Potato Cyst Nematodes and (Tylenchida: Heteroderidae) in Algeria.

Morphological and molecular studies were conducted to characterize the specific identity of 36 isolates of potato cyst nematodes (PCNs) recovered from soil samples collected in several potato producing areas of Algeria. Morphometric data revealed that 44% of isolates contained alone, 28% contained alone and 28% mixtures of the two species. Morphometric values of cysts and second-stage juveniles were generally distributed with slight differences in the expected ranges for both species. Inter- and intraspecific morphometric variability in nematode isolates was noted. Molecular analysis using conventional multiplex PCR with species-specific primers and TaqMan real-time PCR confirmed the morphological identification. In addition, the distribution of both potato cyst nematode species throughout various parts of the country was investigated. In the central areas, the isolates of alone dominate, whereas isolates of alone are more frequent in the southern areas. In the eastern regions, mixed isolates are more representative. Most isolates examined in the western areas are mixtures of the two species or alone. Comparatively, remains the most widely distributed species in its geographic range. This study confirms the presence of two PCN species, and , in Algeria and provides additional information on their biogeographic distribution.