Metabolomic analysis reveals key metabolites and metabolic pathways in Suaeda salsa under salt and drought stress.

Suaeda salsa is an important salt- and drought-tolerant plant with important ecological restoration roles. However, little is known about its underlying molecular regulatory mechanisms. Therefore, understanding the response mechanisms of plants to salt and drought stress is of great importance. In this study, metabolomics analysis was performed to evaluate the effects of salt and drought stress on S. salsa . The experiment consisted of three treatments: (1) control (CK); (2) salt stress (Ps); and (3) drought stress (Pd). The results showed that compared with the control group, S. salsa showed significant differences in phenotypes under salt and drought stress conditions. First, a total of 207 and 292 differential metabolites were identified in the Ps/CK and Pd/CK groups, respectively. Second, some soluble sugars and amino acids, such as raffinose, maltopentoses, D -altro-beptulose, D -proline, valine-proline, proline, tryptophan and glycine-L -leucine, showed increased activity under salt and drought stress conditions, suggesting that these metabolites may be responsible for salt and drought resistance in S. salsa . Third, the flavonoid biosynthetic and phenylalanine metabolic pathways were significantly enriched under both salt and drought stress conditions, indicating that these two metabolic pathways play important roles in salt and drought stress resistance in S. salsa . The findings of this study provide new insights into the salt and drought tolerance mechanisms of S. salsa .

Transcriptomic study of Suaeda salsa in response to salt and drought stress.

Drought and salinity are the main factors limiting agricultural production. Improving crop resistance to relieve land stress is a major challenge in agriculture. The salt-tolerant species Suaeda salsa is a typical indicator of saline soil. It has a strong drought tolerance and can be used as a model plant to study salt and drought tolerance in plants. In this study, transcriptome sequencing and bioinformatic analysis were performed to study gene expression changes in S. salsa under salt and drought stresses, and to screen out differentially expressed genes. The genetic changes were most abundant in cellular processes, metabolic processes, ion binding, signalling, post-translational modifications, protein conversion, and molecular chaperones, suggesting that the above methods may play a significant role in the response of S. salsa to external salt and drought stress. Enrichment analysis showed that carbohydrate metabolic processes, oxidoreductase activity, transmembrane transport, kinase activity, cellular protein modification processes, and ion-binding pathways are involved in the stress response of S. salsa .

Complete chloroplast genome studies of different apple varieties indicated the origin of modern cultivated apples from Malus sieversii and Malus sylvestris.

Background: Apple is one of the most important temperate deciduous fruit trees worldwide, with a wide range of cultivation. In this study, we assessed the variations and phylogenetic relationships between the complete chloroplast genomes of wild and cultivated apples (Malus spp.). Method: We obtained the complete chloroplast genomes of 24 apple varieties using next-generation sequencing technology and compared them with genomes of (downloaded from NCBI) the wild species. Result: The chloroplast genome of Malus is highly conserved, with a genome length of 160,067-160,290 bp, and all have a double-stranded circular tetrad structure. The gene content and sequences of genomes of wild species and cultivated apple were almost the same, but several mutation hotspot regions (psbI-atpA, psbM-psbD, and ndhC-atpE) were detected in these genomes. These regions can provide valuable information for solving specific molecular markers in taxonomic research. Phylogenetic analysis revealed that Malus formed a new clade and four cultivated varieties clustered into a branch with M. sylvestris and M. sieversii, which indicated that M. sylvestris and M. sieversii were the ancestor species of the cultivated apple.

Comparative analyses of chloroplast genomes in 'Red Fuji' apples: low rate of chloroplast genome mutations.

BACKGROUND: Fuji is a vital apple cultivar, and has been propagated clonally for nearly a century. The chloroplast genome variation of Fuji apples in China has not been investigated. METHODS: This study used next-generation high-throughput sequencing and bioinformatics to compare and analyze the chloroplast genome of 24 Red Fuji varieties from nine regions in China. RESULTS: The results showed that the 24 chloroplast genomes were highly conserved in genome size, structure, and organization. The length of the genomes ranged from 160,063 to 160,070 bp, and the GC content was 36.6%. Each of the 24 chloroplast genomes encoded 131 genes, including 84 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The results of repeat sequence detection were consistent; the most common sequence was forward repeats (53.1%), and the least common sequence was complementary repeats (4.1%). The chloroplast genome sequence of Red Fuji was highly conserved. Two indels were detected, but the PI value was 0, and there were no SNP loci. The chloroplast genome variation rate of Red Fuji was low.