Abstract
Background: The tuberous roots of Potentilla anserina (Pan), which are called silverweed cinquefoil roots, serve as a source of starch for the inhabitants of the Qinghai-Tibet Plateau. They are also regarded as a valuable tonic food and herbal medicine in the ethnic medicine system. Starch plays a crucial part in the plant's life cycle, particularly during the growth stage and in response to abiotic stress. Moreover, numerous biological processes and regulatory networks are involved in the synthesis and accumulation of starch. Results: In this research, a combination of transcriptome and metabolomics approaches were employed to analyze the genes related to starch synthesis and degradation in Pan. The crucial genes involved in starch metabolism were identified, and the response characteristics of these genes to drought and low temperature treatments were investigated. Seven AMYs (Alpha-amylases) and 18 BAMs (Beta-amylases) were identified from the genome of Pan. Molecular phylogenetic analyses of AMYs and BAMs derived from 11 species of rosids were conducted respectively. AMYs of Pan and other species were clustered into 3 groups, whereas BAMs were classified into 4 groups. In the tuberous roots, when compared with the control conditions, 2 AMYs and 4 BAMs were upregulated, while 3 BAMs were downregulated, meanwhile, the contents of maltose and glucose-6-phosphate (G6P) were decreased, while the content of glucose-1-phosphate (G1P) was increased under drought treatment. In the tuberous roots under low temperature treatment, 1 BAM was upregulated, while 2 AMYs and 4 BAMs were downregulated compared with control. The response characteristics of AMYs and BAMs to drought and low temperature treatments were further verified through qPCR analysis. Conclusions: In this research, the genes associated with starch synthesis in Pan were characterized, and the functions of AMYs and BAMs in abiotic stress treatments were elucidated. An overview of evolution of AMY and BAM gene families within rosids was also provided.