The conservation biology field underscores the importance of understanding genetic diversity and gene flow within plant populations and the factors that influence them. This study employs Simple Sequence Repeat (SSR) molecular markers to investigate the genetic diversity of the endangered plant species Saussurea involucrata, offering a theoretical foundation for its conservation efforts. Utilizing sequencing results to screen SSR loci, we designed and scrutinized 18 polymorphic microsatellite primers across 112 samples from 11 populations in the Bayinbuluke region. Our findings reveal high genetic diversity (I = 0.837, He = 0.470) and substantial gene flow (Nm = 1.390) among S. involucrata populations (China, Xinjiang), potentially attributed to efficient pollen and seed dispersal mechanisms. Principal Coordinate Analysis (PCoA) indicates a lack of distinct genetic structuring within the Bayinbuluke populations. The cluster analysis using STRUCTURE reflected the genetic structure of S. involucrata to a certain extent compared with PCoA. The results showed that all samples were divided into four groups. To safeguard this species, we advocate for the in situ conservation of all S. involucrata populations in the area. The SSR markers developed in this study provide a valuable resource for future genetic research on S. involucrata.

Within the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) complex, two cryptic species, namely Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED), are important invasive pests affecting global agriculture and horticulture. They were introduced into China sequentially in the mid-1990s and around 2003, respectively. Subsequently, the latter invader MED has outcompeted the earlier invader MEAM1, becoming the dominant population in the field. Although extensive studies have explored the underlying mechanisms driving this shift, the contribution of population genetics remains notably underexplored. In this study, we analyzed the genetic diversity and structure of 22 MED and 8 MEAM1 populations from various regions of China using mitochondrial DNA sequencing and microsatellite genotyping. Our results indicate low and moderate levels of genetic differentiation among geographically separate populations of MED and MEAM1, respectively. Median-joining network analysis of mtCOI gene haplotypes revealed no clear geographic structuring for either, with common haplotypes observed across provinces, although MED had more haplotypes. Comparative analyses revealed that MED presented greater genetic diversity than MEAM1 on the basis of two markers. Furthermore, analysis of molecular variance supported these findings, suggesting that while some genetic variation exists between populations, a significant amount is also present within populations. These findings reveal the population genetics of the two invasive cryptic species of the B. tabaci complex in China and suggest that the disparities in genetic diversity drive the displacement of their populations in the field. This work also provides valuable information on the genetic factors influencing the population dynamics and dominance of these invasive whitefly species.

Examining patterns of genetic diversity are crucial for conservation planning on endangered species, while inferring the underlying process of recent anthropogenic habitat modifications in the context potential long-term demographic changes remains challenging. The globally endangered scaly-sided merganser (SSME), Mergus squamatus, is endemic to a narrow range in Northeast Asia, and its population has recently been contracted into two main breeding areas. Although low genetic diversity has been suggested in the Russian population, the genetic status and demographic history of these individuals have not been fully elucidated. We therefore examined the genetic diversity and structure of the breeding populations of the SSME and investigated the relative importance of historical and recent demographic changes to the present-day pattern of genetic diversity. Using 10 nuclear microsatellite (SSR) markers and mitochondrial DNA (mtDNA) control region sequences, we found limited female-inherited genetic diversity and a high level of nuclear genetic diversity. In addition, analysis of both markers consistently revealed significant but weak divergence between the breeding populations. Inconsistent demographic history parameters calculated from mtDNA and bottleneck analysis results based on SSR suggested a stable historical effective population size. By applying approximate Bayesian computation, it was estimated that populations started to genetically diverge from each other due to recent fragmentation events caused by anthropogenic effects rather than isolation during Last Glacial Maximum (LGM) and post-LGM recolonization. These results suggest that limited historical population size and shallow evolutionary history may be potential factors contributing to the contemporary genetic diversity pattern of breeding SSME populations. Conservation efforts should focus on protecting the current breeding habitats from further destruction, with priority given to both the Russian and Chinese population, as well as restoring the connected suitable breeding grounds.

Understanding how anthropogenic disturbances affect the genetics of tree species is crucial; however, how tree populations in the wild can tolerate these activities remains unexplored. Given the ongoing and intensifying anthropogenic disturbances, we conducted a study using Ailanthus altissima to gain new insights into the effects of these pressures on genetic variability in undisturbed and disturbed forests. We analyzed the genetic diversity and population structure of A. altissima using nuclear (EST-SSR) and chloroplast (cpSSR) microsatellite markers. The genetic diversity across the 34 studied populations based on EST-SSRs was found to be moderate to high (nH E = 0.547-0.772) with a mean nH E of 0.680. Bayesian clustering, principal coordinate analysis (PCoA), and discriminant analysis of principal component (DAPC) consistently divided the populations into three distinct groups based on EST-SSRs. Allelic combinations of 92 different chloroplast size variants from 10 cpSSR loci resulted in a total of 292 chloroplast haplotypes. The mean haplotype diversity was relatively high (cpH E = 0.941), and the mean haplotype richness was 2.690, averaged across the 34 populations of A. altissima. Values of F ST in A. altissima from chloroplast and nuclear markers were 0.509 and 0.126, respectively. Modeling results showed evidence for population range contraction during the Last Glacial Maximum with subsequent population expansion in the Holocene and the future. Although genetic variation did not differ substantially across disturbed and undisturbed sites, there were small trends indicating higher genetic diversity and population bottlenecks in disturbed forests. As a result, disrupted ecosystems might display surprising genetic patterns that are difficult to predict and should not be overlooked.

Dysomma anguillare is a demersal eel widespread distributing in tropical waters of the Indo-West Pacific and Atlantic. As an important component of the coastal fishery and marine ecosystem, the lack of genomic information for this species severely restricts the progress of relevant researches. In this study, the abecedarian genome-wide characteristics and phylogenetic relationships analyses were carried out based on next-generation sequencing (NGS) platform. The revised genome size was approximately 1 310 Mb, with the largest scaffold length reaching 23 878 bp through K-mer (K = 17) method. The heterozygosity, repetitive rate and average GC content were about 0.94%, 51.93% and 42.23%, respectively. A total of 1 160 104 microsatellite motifs were identified from the de novo assembled genome of D. anguillare, in which dinucleotide repeats accounted for the largest proportion (592 234, 51.05%), the highest occurrence frequency (14.58%) as well as the largest relative abundance (379.27/Mb). The high-polymorphic and moderate-polymorphic loci composed around 73% of the total single sequence repeats (SSRs), showing a latent capacity for subsequent population genetic structure and genetic diversity appraisal researches. Another byproduct of whole-genome sequencing, the double-stranded and circular mitogenome (16 690 bp) was assembled to investigate the evolutionary relationships of D. anguillare. The phylogenic tree constructed with maximum likelihood (ML) method showed that D. anguillare was closely related to Synaphobranchidae species, and the molecular systematic results further supported classical taxonomy status of D. anguillare.

The Himalayan marmot Marmota himalayana is widely distributed across the Qinghai-Tibetan Plateau and lives in social groups, yet the mating system of this highly social marmot species is unknown. In this study, the genetic mating system of Himalayan marmots was investigated using microsatellite markers to determine which mating strategies individuals employ. Results revealed that both monogamous and polygamous mating relationships occur in our study population, indicating that the genetic mating system of this marmot species is promiscuity. This study presents the first genetic evidence on the mating system for Himalayan marmots, yet indicates that further studies employing both a genetic and behavioral framework are needed to better understand the social structure and reproductive biology of this marmot species.

Schistosoma japonicum had once caused the greatest disease burden in China and has still been transmitted in some hilly areas, for example, in Shitai of Anhui province, where rodents are projected to be the main reservoir. This may lead to a critical need of molecular tools with high efficiency in monitoring the dynamic of the rodent-associated S. japonicum, as an appropriate amount of schistosome input can re-establish its life cycle in a place with snails and then result in the re-emergence of schistosomiasis. Therefore, the goal of this study was to develop high polymorphic microsatellites from the whole genome of rodent-associated S. japonicum strain to monitor its transmission dynamic. We sampled the hilly schistosome isolate from Shitai of Anhui in China and sequenced the parasite with the next-generation sequencing technology. The whole genome was assembled with four different approaches. We then developed 71 microsatellite markers at a genome-wide scale throughout two best assembled genomes. Based on their chromosome mapping and the expected length of targeted sequences, we selected 24 markers for the development of multiplex reactions. Two multiplexes composed of 10 loci were finally developed, and their potential was revealed by their successful application on and capturing the genetic diversity of three schistosome populations. The selected 10 markers, each with clear chromosome location and characteristics, will be greatly useful in tracing the dispersal pathways or/and dynamics of the rodent-associated S. japonicum or others in the hilly area of China or elsewhere.

Chinese kale is a widely cultivated plant in the genus Brassica in the family Brassicaceae. The origin of Brassica has been studied extensively, but the origin of Chinese kale remains unclear. In contrast to Brassica oleracea, which originated in the Mediterranean region, Chinese kale originated in southern China. The chloroplast genome is often used for phylogenetic analysis because of its high conservatism. Fifteen pairs of universal primers were used to amplify the chloroplast genomes of white-flower Chinese kale (Brassica oleracea var. alboglabra cv. Sijicutiao (SJCT)) and yellow-flower Chinese kale (Brassica oleracea var. alboglabra cv. Fuzhouhuanghua (FZHH)) via PCR. The lengths of the chloroplast genomes were 153,365 bp (SJCT) and 153,420 bp (FZHH) and both contained 87 protein-coding genes and eight rRNA genes. There were 36 tRNA genes in SJCT and 35 tRNA genes in FZHH. The chloroplast genomes of both Chinese kale varieties, along with eight other Brassicaceae, were analyzed. Simple sequence repeats, long repeats, and variable regions of DNA barcodes were identified. An analysis of inverted repeat boundaries, relative synonymous codon usage, and synteny revealed high similarity among the ten species, albeit the slight differences that were observed. The Ka/Ks ratios and phylogenetic analysis suggest that Chinese kale is a variant of B. oleracea. The phylogenetic tree shows that both Chinese kale varieties and B. oleracea var. oleracea were clustered in a single group. The results of this study suggest that white and yellow flower Chinese kale comprise a monophyletic group and that their differences in flower color arose late in the process of artificial cultivation. Our results also provide data that will aid future research on genetics, evolution, and germplasm resources of Brassicaceae.

Suaeda aralocaspica, which is an annual halophyte, grows in saline deserts in Central Asia with potential use in saline soil reclamation and salt tolerance breeding. Studying its genetic diversity is critical for effective conservation and breeding programs. In this study, we aimed to develop a set of polymorphic microsatellite markers to analyze the genetic diversity of S. aralocaspica. We identified 177,805 SSRs from the S. aralocaspica genome, with an average length of 19.49 bp, which were present at a density of 393.37 SSR/Mb. Trinucleotide repeats dominated (75.74%) different types of motifs, and the main motif was CAA/TTG (44.25%). We successfully developed 38 SSR markers that exhibited substantial polymorphism, displaying an average of 6.18 alleles with accompanying average polymorphism information content (PIC) value of 0.516. The markers were used to evaluate the genetic diversity of 52 individuals collected from three populations of S. aralocaspica in Xinjiang, China. The results showed that the genetic diversity was moderate to high, with a mean expected heterozygosity (He) of 0.614, a mean Shannon\'s information index (I) of 1.23, and a mean genetic differentiation index (Fst) of 0.263. The SSR markers developed in this study provide a valuable resource for future genetic studies and breeding programs of S. aralocaspica, and even other species in Suaeda.

This paper reports the first account about dynamic changes on genetic diversity and population structure of Leptobotiamicrophthalma in the Yangtze River drainage due to dam constructions. The genetic diversity and population structure of twelve populations of L.microphthalma collected in 2010 and 2020 were estimated using 12 nuclear microsatellite markers. Reduction of genetic diversity between 2010 and 2020 was not significant in a paired t-test (p > 0.05), but population structure of L.microphthalma had a tendency to change: the genetic differentiation (Fst) among the five populations collected in 2010 were all insignificant (p > 0.05). However, differentiation (Fst) among some populations collected in 2020 were significant (p < 0.05), which indicated the population structure of L.microphthalma was changing. Correlation analysis indicated that negative correlations between the genetic diversities and geographical elevations among populations were significant for seven populations collected in 2020 (r = -0.819, p = 0.039), which means that populations of L.microphthalma in high elevation regions were more vulnerable than those in low elevation regions. Finally, some suggestions for conservation and restoration are proposed, such as artificial propagation, to prevent the further reduction of genetic diversity and population resources.