Studies on the nematode fauna and biodiversity of Şanlıurfa

The study conducted to examine the biodiversity of terrestrial nematodes in agricultural and nonagricultural areas of Sanlıurfa, Turkey. The area is defined with the semi-arid features. The area, consists of irrigated and dry cultures, has been divided into 5 sub-regions regarding the geographic and ecological boundaries. Samples were taken twice a year, one in the mid-spring and second in the mid-fall for 3 years, in 2003-2005. Nematode fauna has been represented by 26 species, 28 genus, and 4 families, belonging to 8 orders. The proportions of plant parasitic and free-living nematodes are % 39 and % 61, respectively. Plant parasitic nematodes are represented by 26 species and 6 genera belonging to 2 orders (Tylenchida and Dorylaimida); bacterivores are represented by 4 families and 10 genus belonging to 4 orders (Rhabditida, Cephalobida, Diplogaterida and Monhysterida); fungivores are represented by 3 genus belonging to 2 orders (Aphelenchida and Tylenchida); predators are represented by 2 genus belonging to 2 orders (Mononchhida and Aphelenchida) and the omnivores 7 genus belonging to 1 order (Dorylaimida). Diversity of nematode communities has been influenced by the ecosystem?s plant cover (crop plant) more than any other diversity drivers such as soil type and geographical differences. The mean values of Maturity index (MI), Shannon diversity (H?) and Evenness indices were calculated 2.3, 2.1 and 0.8, respectively; suggesting a somewhat poor free-living nematode faunal structure of Sanlıurfa. Key Words: Sanlıurfa, biodiversity, nematode fauna, plant-parasitic nematodes and free-living nematodes.