Abstract: In order to quickly detect the conditions of Aphelenchoides besseyi contamination in millet seeds and understand the population variations of Aphelenchoides besseyi from different regions, a total of 99 millet seed samples collected from different millet production regions of China were detected by PCR technology, and the population variation of Aphelenchoides besseyi was analyzed. The results showed that the specific primers designed according to the 28S rRNA-D2/D3 fragment of Aphelenchoides besseyi had a high specificity and sensitivity to millet nematodes, and could amplify a fragment of 245 bp with the lowest test concentration of 0.125 ng/μL Aphelenchoides besseyi. Among the 99 millet seed samples, 33 samples were detected to be contaminated, in which the contamination rates ranged from 33.3% to 100%, and they mainly distributed in spring millet areas. The sequence analysis of 28S rRNA fragments from 33 positive samples revealed that there were 29 variable sites and 22 haplotypes, of which the haplotype AB1 was the dominant haplotype. The haplotype genetic diversity of Aphelenchoides besseyi was the most abundant in Zhangjiakou, Hebei Province and Songshan District, Inner Mongolia. In this study, a PCR-based detection method was established to detect Aphelenchoides besseyi in millet seeds with a good specificity and high sensitivity, which could be used to detect the millet seeds carrying Aphelenchoides besseyi. The millet nematode is a major disease in summer millet areas, but with the millet exchange between spring and summer millet areas, it has become a disease in spring millet area. The seed carrier may be the main primary infection source. The 28S rRNA sequences of Aphelenchoides besseyi from different geographic origins were diverse, and AB1 was the dominant haplotype.

Key words: Foxtail millet, Aphelenchoides besseyi, Seed-borne, Polymerase chain reaction, Haplotype

CLC Number: 

• S515