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•Glutathione peroxidase (GPX) is a family of antioxidant enzymes that catalyze the reduction of hydrogen peroxide (H2O2) and defend the cells from oxidative stress.•Identified the five GPXgenes in the N. coloratagenome and further divided into four main groups based on phylogenetic analyses.•NcGPX proteins have MW ranged 18.798–26.292 kDa and conserved exon-intron structures and motifs.•NcGPXexhibited segmental duplications and collinearity exists between N. thermarum.•RT-qPCR analysis revealed that all NcGPXshave dynamic expression especially NcGPX3and NcGPX5could be critical for abiotic stress improvement.

Context Heat shock proteins play a vital role in cellular homeostasis by protecting proteins against various environmental stresses, which facilitates the survival of plants under unfavourable conditions. Aims We aimed to provide the first comprehensive genomic and expression analysis of the HSP70 gene family in betel palm (Areca catechu) to elucidate its role in heat stress response. Methods Genomic analysis revealed 34 putative HSP70 genes distributed across 13 chromosomes. These were renamed AcatHSP70 and classified into five subfamilies (A–E) based on phylogenetic analysis. These genes are mostly localised in the chloroplast, cytoplasm, and nucleus. Gene ontology revealed that these genes are mostly involved in heat stress. The gene duplication events of HSP70 genes involved only segmental duplications. We subjected betel palm seedlings (2years old) to heat stress under controlled conditions for 30days at high, low, and room temperatures for expression analyses of HSP70 genes. Key results Expression analysis revealed eight putative candidate genes (AcatHSP70-3, AcatHSP70-13, AcatHSP70-22, AcatHSP70-19, AcatHSP70-21, AcatHSP70-24, AcatHSP70-25, and AcatHSP70-26) that showed significantly higher expression under high-temperature stress. AcatHSP70-5 showed higher expression under low-temperature treatment, and AcatHSP70-16 was responsive at room temperature treatment. Conclusion We conclude that the majority of AcatHSP70 genes play a crucial role under thermal stress conditions, and respond to high-temperature stress as shown by the quantitative reverse transcription polymerase chain reaction analysis. Implications This comprehensive characterisation of the HSP70 gene family provides novel insights into the thermal protection mechanisms of betel palms in changing climates.

Fragaria vesca,commonly known as wild or woodland strawberry, is the most widely distributed diploid Fragariaspecies and is native to Europe and Asia. Because of its small plant size, low heterozygosity, and relative ease of genetic transformation, F. vescahas been a model plant for fruit research since the publication of its Illumina-based genome in 2011. However, its genomic contribution to octoploid cultivated strawberry remains a long-standing question. Here, we de novoassembled and annotated a telomere-to-telomere, gap-free genome of F. vesca‘Hawaii 4’, with all seven chromosomes assembled into single contigs, providing the highest completeness and assembly quality to date. The gap-free genome is 220 785 082 bp in length and encodes 36 173 protein-coding gene models, including 1153 newly annotated genes. All 14 telomeres and seven centromeres were annotated within the seven chromosomes. Among the three previously recognized wild diploid strawberry ancestors, F. vesca, F. iinumae, and F. viridis, phylogenomic analysis showed that F. vescaand F. viridisare the ancestors of the cultivated octoploid strawberry F.× ananassa, and F. vescais its closest relative. Three subgenomes of F.× ananassabelong to the F. vescagroup, and one is sister to F. viridis. We anticipate that this high-quality, telomere-to-telomere, gap-free F. vescagenome, combined with our phylogenomic inference of the origin of cultivated strawberry, will provide insight into the genomic evolution of Fragariaand facilitate strawberry genetics and molecular breeding.