Existence, molecular identification and genetic variation of new isolates of seed gall nematode Anguina tritici parasitizing on wheat and barley in Iraq

Abstract EN

This study aimed to investigate the existence of wheat seed gall nematode Anguina tritici in the silos and some wheat fileds in Duhok province / Kurdistan Region - Iraq.,and diagnose four new isolates of this nematode on wheat and one isolate on barley collected from different loactions in Iraq.The results indiacted that wheat impurities samples were infested with seed galls by 66 % as the highest percentager in silo of Faidia during 2020, while the lowest (6%) recoded in the silo of Zakho during the same year.The highest disease incidence was recorded in the wheat fields of Akre by 34.6%,while the lowest (2%) in the wheat fields of Semel.

Molecular identification results revealed that the bands of amplified DNA products of all nematode isolates were visualized by agarose gel electrophoresis in the same position ("~" up to 750 bp).Sequencing of the partial gene 5.8S rRNA gene confirmed that all nematode isolates belong to seed gall nematode A.tritici, also a description of their accession number by blast program showed the same percentage identitiy (100 %), and their comparision by a DNA Dot Plot emphasized that they are genetically similar.

Results of phylogenetic tree analysis showed grouping of nematode isolates with each other and with the other two isolates of the same species from Iraq,whilst nucleotide variations increased with other nematode species of the same genus,and increased more with other nematode species of the same family (Anguinidae).