Cereal cyst nematodes : molecular identification and quantification, and screening for resistance in wheat

A survey was conducted in north-eastern Syria to assess the distribution of the cereal cyst nematodes (CCN). The study revealed that 62% of the fields were infested with three Heterodera species: H. latipons (76%), H. avenae (31%), and H. filipjevi (9%). Molecular identification and quantification is an accurate, rapid and sensitive method. Therefore, the actin-1 gene was successfully used to develop a species-specific PCR assay to detect H. latipons; and the mitochondrial cytochrome oxidase subunit 1 (COI) gene was used to develop two species-specific PCR assays for the identification of H. avenae and H. filipjevi. Also, the COI gene was used to develop two qPCR assays for the identification and quantification of H. avenae and H. latipons. The use of resistant hosts for nematode management is considered cost-efficient and environmentally friendly. Hence, a total of 217 synthetic winter wheat lines were screened (phenotyped) for resistance to H. filipjevi in the growth chamber. The same lines were genotyped using the Amplified Fragment Length Polymorphism (AFLP) technique. Phenotyping showed that some lines are promising because of a low number of newly developed cysts; those lines are considered resistant and moderate resistant and can be used for further breeding of resistant cultivars against cereal cyst nematodes