Genetic diversity and population genetic structure of Neillia incisa in China: implications for genetic conservation

Key message We analyzed the genetic diversity and population genetic structure of Neillia incisa (Thunb.) Zabel using EST-SSR markers. Neillia incisa (Thunb.) Zabel is an undomesticated plant species which is distributed along the coastal areas of East Asia. N. incisa has rarely been planted in cities despite its potential usefulness in removing particulate air pollution. Our study utilized EST-SSR markers to investigate the genetic diversity of 122 wild N. incisa individuals from five populations, including Anshan (AS), Zhuanghe (ZH), Changhai (CH), Kunyu (KU) and Laoshan (LS). All indexes measured indicated moderate polymorphism. The CH population was found to have the highest genetic diversity, while the AS population was observed to have the lowest. The average genetic differentiation coefficient (Fst) of the five N. incisa populations was found to be 0.2075. Analysis of molecular variance revealed that the genetic variation observed among various populations was only 16.99% of the total variation, while the genetic variation within populations accounted for 83.01% of the total variation. Principal coordinate analysis, unweighted pair group with arithmetic mean clustering and genetic structure analysis revealed that the five N. incisa populations could be differentiated into three groups. ZH was found to group with CH, LS grouped with KU and AS formed its own cluster. The results of this study provide a preliminary genetic basis for the use and conservation of N. incisa.