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• Population genetic analyses and ecological niche data did not support Aconitum pendulum and A. flavum as two separate species. • Gene flow and genetic drift may weaken the genetic difference and its correlation with geographical distance. • The bottleneck effect was detected among populations of A. pendulum and A. flavum during the Last glacial maximum. • Human activity, such as overexploitation causing habitat fragmentation, might be one of the factors that threat to the survival of A. pendulum and A. flavum in the current period. As species are fundamental units of evolutionary biology research, accurate species delimitation plays a crucial role in current biodiversity management. The Qinghai-Tibet Plateau (QTP) comprises one of the global biodiversity hotspots, and plant speciation and its evolutionary history in this region still need much research. Aconitum pendulum and A. flavum (Ranuculaceae) are mainly distributed in the QTP and its adjacent regions. The two species have extremely similar morphological characteristics, and their evolutionary relationship is still controversial. In this study, we collected 244 individuals in 14 populations from the main distribution areas of the two species. Genome-wide single-nucleotide polymorphisms (SNPs) from genotyping-by-sequencing (GBS) of A. pendulum and A. flavum were obtained to decipher the taxonomic delimitation and explore the evolutionary history. We performed neighbor-joining (NJ), PCA, structure, and niche overlap analyses. None of them support that A. pendulum and A. flavum can be considered as two separate species. In addition, the genetic difference between species is less than that among populations. We propose merging the two species into one. We also found that the genetic difference between the two species was not associated with morphological species or geographic distance. Gene flow and genetic drift may play a crucial role in weakening the correlation between genetic distance and geographical distance. A bottleneck effect occurred in the two species during the last glacial maximum. Based on the Maxent and Stairway Plot results, we inferred that A. pendulum and A. flavum still had large survival ranges during the LGM, similar to other cold-tolerant species. Furthermore, human activity, such as overexploitation causing habitat fragmentation, might be one of the factors that threat to the survival of A. pendulum and A. flavum in the current period. [ABSTRACT FROM AUTHOR]

A multiplex polymerase chain reaction (PCR) method was developed to detect and distinguish goose parvovirus (GPV), waterfowl reovirus (WRV), and goose astrovirus (GAstV). Three pairs of primers were designed based on conserved regions in the genomic sequences of these enteric viruses and were used to specifically amplify targeted fragments of 493 bp from the viral protein 3 (VP3) gene of GPV, 300 bp from the sigma A-encoding gene of WRV, and 156 bp from the capsid protein-encoding gene of GAstV. The results showed that the primers can specifically amplify target fragments, without any cross-amplification with other viruses, indicating that the method had good specificity. A sensitivity test showed that the detection limit of the multiplex PCR method was 1 × 103 viral copies. A total of 102 field samples from Muscovy ducks with clinically suspected diseases were evaluated using the newly developed multiplex PCR method. The ratio of positive samples to total samples for GPV, WRV, and GAstV was 73.53% (75/102) for multiplex PCR and was 73.53% (75/102) for routine PCR. Seventy-five positive samples were detected by both methods, for a coincidence ratio of 100%. This multiplex PCR method can simultaneously detect GPV, WRV, and GAstV, which are associated with viral enteritis, thereby providing a specific, sensitive, efficient, and accurate new tool for clinical diagnosis and laboratory epidemiological investigations. • A multiplex PCR assay was developed for simultaneous detection for GPV, WRV, and GAstV in Muscovy duck flocks, with good specificity, good accuracy, and high sensitivity. • The multiplex PCR was able to detect at least 1 × 103 viral copies of GPV, WRV, and GAstV. • The multiplex PCR developed is a useful tool for clinical diagnosis of single virus and/or mixed infections in Muscovy duck. [ABSTRACT FROM AUTHOR]