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.

The desert moss Syntrichia caninervis has proven to be an excellent plant material for mining resistance genes. The aldehyde dehydrogenase 21 (ScALDH21) gene from S. caninervis has been shown to confer tolerance to salt and drought, but it is unclear how the transgene ScALDH21 regulates tolerance to abiotic stresses in cotton. In the present work, we studied the physiological and transcriptome analyses of non-transgenic (NT) and transgenic ScALDH21 cotton (L96) at 0 day, 2 days, and 5 days after salt stress. Through intergroup comparisons and a weighted correlation network analysis (WGCNA), we found that there were significant differences between NT and L96 cotton in the plant hormone, Ca²⁺, and mitogen-activated protein kinase (MAPK) signaling pathways as well as for photosynthesis and carbohydrate metabolism. Overexpression of ScALDH21 significantly increased the expression of stress-related genes in L96 compared to NT cotton under both normal growth and salt stress conditions. These data suggest that the ScALDH21 transgene can scavenge more reactive oxygen species (ROS) in vivo relative to NT cotton and improve cotton resistance to salt stress by increasing the expression of stress-responsive genes, responding quickly to stress stimuli, enhancing photosynthesis and improving carbohydrate metabolism. Therefore, ScALDH21 is a promising candidate gene to improve resistance to salt stress, and the application of this gene in cotton provides new insights into molecular plant breeding.

Desiccation is typically fatal, but a small number of land plants have evolved vegetative desiccation tolerance (VDT), allowing them to dry without dying through a process called anhydrobiosis. Advances in sequencing technologies have enabled the investigation of genomes for desiccation-tolerant plants over the past decade. However, a dedicated and integrated database for these valuable genomic resources has been lacking. Our prolonged interest in VDT plant genomes motivated us to create the “Drying without Dying” database, which contains a total of 16 VDT-related plant genomes (including 10 mosses) and incorporates 10 genomes that are closely related to VDT plants. The database features bioinformatic tools, such as blast and homologous cluster search, sequence retrieval, Gene Ontology term and metabolic pathway enrichment statistics, expression profiling, co-expression network extraction, and JBrowser exploration for each genome. To demonstrate its utility, we conducted tailored PFAM family statistical analyses, and we discovered that the drought-responsive ABA transporter AWPM-19 family is significantly tandemly duplicated in all bryophytes but rarely so in tracheophytes. Transcriptomic investigations also revealed that response patterns following desiccation diverged between bryophytes and angiosperms. Combined, the analyses provided genomic and transcriptomic evidence supporting a possible divergence and lineage-specific evolution of VDT in plants. The database can be accessed at http://desiccation.novogene.com. We expect this initial release of the “Drying without Dying” plant genome database will facilitate future discovery of VDT genetic resources.

Walnuts have substantial economic value and are of significant interest being a wild-cultivated species. The study has re-sequenced the entire genome of the wild walnut, aligning it with the walnut reference genome, to identify 2,021,717 single nucleotide polymorphisms (SNPs). These were used to examine the genetics of 130 wild walnut samples collected from three countries. Utilizing structural and principal component analysis, the walnut samples from Central Asia were classified into four populations: Ili ah in Xinjiang (I), Dushanbe region in Tajikistan (II), Sary-Chelek, Arslanbob in Kara-Alma regions of Kyrgyzstan (III), and Kok-Tundy region of Kyrgyzstan (IV). The 4 groups showed large differences in nucleotide diversity, population differentiation, and linkage disequilibrium decay, as well as gene flow among them. The present geographic distribution of these populations does not align with the genetic distribution pattern as the populations of Central Asian wild walnuts have experienced similar population dynamics in the past, i.e., the highest effective population size at ca. 6 Ma, two sharp population declines at 6 and 0.2 Ma, and convergence at ca. 0.2 Ma. The genetic distribution patterns are better explained by human activity, notably through archaeological findings of walnut use and the influence of the Silk Road, rather than by current geographic distributions.

The common walnut (Juglans regia L.), a species of significant economic and ecological importance, along with its variant, holds developmental value. Simple sequence repeat (SSR) markers are used as an effective method for material identification due to their co-dominant inheritance. In this work, a total of 357629 SSR loci were searched based on previously published walnut genome sequences, with a density of 662.28 (SSRs/Mb). The majority of all these loci were found to be single nucleotide A/T (58.49%), followed by the dinucleotide AT (19.48%). Based on the results of genome-wide SSR site design, 22 effective primer pairs were designed and screened to analyze the genetic diversity of 48 wild walnut samples from three countries. Each locus had an average of 5.17 effective alleles (Ne), with an average polymorphism information content (PIC) of 0.71, average heterozygosity (He) of 0.52, and average genetic differentiation index (Fst) of 0.09. The analysis of 48 wild walnut samples from three countries (Kyrgyzstan, Tajikistan, and China) using the unweighted pairwise clustering method and arithmetic mean (UPGMA) along with principal coordinate analysis revealed the division of all samples into three groups. In summary, these novel SSR markers serve as a reference for the identification of wild walnut germplasm in Central Asia and for the development and utilization of wild walnut seed resources.

The Munake grape is a local variety of grape that is widely distributed in Xinjiang, China. This study aims to clarify the genetic structure of the Munake grape population, characterize genetic differentiation and gene flow among populations, gather germplasm, and establish the core germplasm collection. In total, 144 samples were collected from eight geographic populations. Twenty-two SSR markers were used to characterize the genetic diversity as well as the genetic structure of Munake grape germplasm and to establish the core germplasm collection. At each site, the average number of effective alleles (Ne) was 5.019. Overall, genetic diversity was high in the various geographic populations of Munake grapes. Polymorphic information content (PIC) ranged from 0.501 to 0.908, with an average of 0.728. Estimates of genetic differentiation and gene flow indicated that the Artux population had significant genetic differences from the other populations. Screening results indicated that a sampling proportion of 95% of the sample was required to achieve 100% allelic coverage, or a sampling proportion of 65% for 95% allelic coverage. This analysis was based on conventional genetic diversity indicators, with a core germplasm diversity index of 95% coverage. Characterization of the genetic diversity of germplasm from 144 Munake grapes not only provides valuable resources for future genetic mapping and functional genome research, but also facilitates the utilization of core germplasm and molecular breeding of Munake grapes.