Cereal cyst nematodes are one of the most important soil-borne pathogens of cereals throughout the world. This group of nematodes is considered the most economically damaging pathogens of wheat and barley in Iran. In the present study, a series experiments were conducted during 2007-2010 to determine the distribution and population density of cereal cyst nematodes and to examine the biology of Heterodera latipons in the winter wheat cv. Sardari in a microplot under rain-fed conditions over two successive years in Markazi province in central Iran. Results of field survey showed that 40% of the fields were infested with at least one species of either Heterodera filipjevi or H. latipons. H. filipjevi was most prevalent in Farmahin, Tafresh and Khomein, with H. latipons being found in Khomein and Zarandieh regions. Female nematodes were also observed in Bromus tectarum, Hordeum disticum and Secale cereale, which are new host records for H. filipjevi. Also, H. filipjevi and H. latipons were found in combination with root and crown rot fungi, Bipolaris sorokiniana, Fusarium culmorum, F. solani and Gaeumannomyces graminis, in some fields. Results of the biology study showed that H. latipons developed only one generation in each wheat growing season and its developmental stages are closely related to the climate conditions and the host plant growth. Immature females were first evident on roots in the third week of March to early April, with soil temperatures of 11.8-13.3degreesC. The mature females containing eggs with embryo were observed in third week of April until early May, when the soil temperature was 14.2-15.3degreesC. H. latipons completed its life-cycle in about 145-150 days in wheat.
