Association of Globodera rostochiensis (Nematoda) with Stunted and Chlorotic Potato Plants in Yunnan and Sichuan Provinces in China

On a global basis, potato cyst nematodes (Globodera spp. Skarbilovich 1959 [Behrens 1975]) are one of the most serious soilborne pathogens in potato (Solanum tuberosum L.) production. In 2019 to 2020, 188 soil samples were taken from rhizosphere soil associated with the roots of stunted and chlorotic potato plants in the main potato-growing areas of Yunnan and Sichuan Provinces of China. Globodera rostochiensis Wollenweber 1923 (Skarbilovich 1959) was recovered from 112 of the samples. Nematode identification was as confirmed by morphometric, light microscopy, electron microscopy, and molecular methodologies. Population densities of G. rostochiensis ranged from 47.0 to 69.0 eggs/g of soil. A BLASTn homology search program was used to compare the sequences of populations of G. rostrochienses from Yunnan and Sichuan Provinces with populations of other Heteroderinae spp. and populations of G. rostochiensis from other nations. Although potato has been grown in China for at least 400 years and the nation produces more potato than any other country, potato cyst nematodes were not reported in China until 2022.