Dataset Information

Transgenerational effects of water-deficit and heat stress on germination and seedling vigour – new insights from durum wheat microRNAs

ABSTRACT: Water deficiency and heat stress can severely limit crop production and quality. Stress imposed on the parents during reproduction could have transgenerational effects on their progeny. Seeds with different origins can vary significantly in germination time-course and early growth. Here, we investigated how water-deficit and heat stress on parental durum wheat plants affected seedling establishment of the subsequent generation. One stress-tolerant and one stress-sensitive Australian durum genotype were used. Seeds were collected from parents with or without exposure to stress during reproduction. Generally stress on the previous generation negatively affected seed germination and seedling vigour, but to a lesser extent in the tolerant variety. Small RNA sequencing utilising the new durum genome assembly has revealed significant differences in microRNA (miRNA) expression in the two genotypes. A bioinformatics approach was used to identify multiple miRNA targets which have critical molecular functions in stress adaptation and plant development and could therefore contribute to the phenotypic differences observed. Our data provides the first confirmation of the transgenerational effects of reproductive-stage stress on germination and seedling establishment in durum wheat. New insights gained on the epigenetic level indicate that durum miRNAs could be key factors in optimising seed vigour for superior breeding germplasm and/or varieties.

ORGANISM(S): Triticum turgidum subsp. durum

PROVIDER: GSE143454 | GEO | 2020/02/04

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Background: Waterlogging was one of the most serious abiotic stresses in wheat-growing regions of China. There were great differences in waterlogging tolerance among different wheat varieties, and the mechanism of waterlogging tolerance of wheat seeds during germination was unclear. Methods: In order to reveal the adaptability of wheat to waterlogging stress during germination, we analyzed the germination rate and anatomical structure of three wheat seeds, ‘Zhoumai 22’, ‘Bainong 207’ and ‘Bainong 607’. At the same time, Illumina sequencing technology was used to determine the transcriptome of these three wheat varieties during germination. Results: The results showed that there was no significant difference between the germination rate of ‘Bainong 207’ after 3 days of waterlogging treatment and that of the control seeds. However, under waterlogging stress, the degree of emulsification and degradation of endosperm cells was higher than that of the control treatment, and starch granules in endosperm were significantly reduced. Transcriptome data were obtained from seed samples (a total of 18 samples) of three wheat varieties under waterlogging and control treatment. A total of 2,775 differentially expressed genes (DEGs) were identified by comprehensive analysis. In addition, by analyzing the correlation between the expression levels of DEGs and seed germination rates in three wheat varieties under waterlogging stress, it was found that the relative expression levels of 563 and 398 genes were positively and negatively correlated with the germination rate of wheat seeds, respectively. The GO and KEGG analysis found that the difference in waterlogging tolerance of the three wheat varieties was related to the abundance of key genes involved in the glycolysis pathway, the starch and sucrose metabolism pathway, and the lactose metabolism pathway. The ethanol dehydrogenase (ADH) gene in the endosperm of ‘Bainong 607’ was immediately induced after a short period of waterlogging, and the energy provided by glycolysis pathway enabled the seeds of ‘Bainong 607’ to germinate as early as possible, while the expression level of AP2/ERF transcription factor was up-regulated to further enhance its waterlogging tolerance. Conclusions: In general, this study provided a deeper understanding of the mechanisms by which different wheat varieties respond to waterlogging stress during germination.

Project description:Background: MicroRNAs are endogenous small noncoding RNAs that play critical roles in plant abiotic stress responses. The interaction between miRNA-mRNA targets and their regulatory pathways in response to water deficit stress has been investigated in many plant species. However, the miRNA transcriptome of durum wheat (Triticum turgidum L. ssp. durum) is poorly characterised, with little known about miRNA functions related to water deficit stress. Yield loss in durum wheat can be exacerbated due to minimal rainfall in the early reproductive stages of development during Spring in Australia. This study describes genotypic differences in the miRNAome between water deficit tolerant/sensitive durum, using flag leaf and developing head tissue, and more specifically identifies miRNAs associated with water deficit stress. Results: Small RNA libraries (96 in total) were constructed from flag leaf and developing head tissues of four durum genotypes (Tamaroi, Yawa, EGA Bellaroi, Tjilkuri), with or without water deficit stress. Illumina sequencing and subsequent analysis detected 110 conserved miRNAs and 159 novel candidate miRNA hairpins. Statistical analysis of the abundance of sequencing reads revealed 66 conserved miRNAs and five novel miRNA hairpins showing differential expression under water deficit stress. During stress, several conserved and novel miRNAs showed unambiguous inverted regulatory profiles between the durum genotypes studied. Several miRNAs were also identified to have different abundance in the flag leaf compared to the developing head regardless of treatment. Predicted mRNA targets from four novel durum miRNAs were characterised using Gene Ontology (GO) which revealed functions common to stress responses and plant development. Conclusion: For the first time, we present a comprehensive study of the miRNA transcriptome of flag leaf and developing head tissues in different durum genotypes under water deficit stress. The identification of differentially expressed miRNAs provides molecular evidence that miRNAs are potential determinants of water stress tolerance in durum wheat. GO analysis of predicted targets contributes to the understanding of genotype-specific physiological responses leading to stress tolerance capacity. Further functional analysis of specific stress responsive miRNAs identified, and their interaction with mRNA targets is ongoing and will assist in developing future durum wheat varieties with enhanced water deficit stress tolerance.

Dataset Information

Transgenerational effects of water-deficit and heat stress on germination and seedling vigour – new insights from durum wheat microRNAs

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure