GSE168094
Nitrogen starvation-responsive microRNAs are affected by transgenerational stress in durum wheat seedlings
Stress events have transgenerational effects that influence plant growth in the subsequent generation. In Mediterranean regions, water-deficit and heat (WH) stress is a frequent issue that negatively affects crop yield and quality. Nitrogen (N) is an essential plant macronutrient and often a yield-limiting factor for crops. Here, the response of durum wheat seedlings to N starvation under the transgenerational effects of WH stress were investigated in two genotypes. Both genotypes showed significant reduction in seedling height, leaf number, shoot and root weight (fresh and dry), primary root length and chlorophyll content under N starvation stress. However, in the WH stress-tolerant genotype, the reduction rate of most traits were lower in progeny from the stressed parents than progeny from the control parents. Small RNA sequencing identified 1,534 microRNAs in different treatment groups. Differentially expressed microRNAs (DEMs) were characterized subject to N starvation, parental stress and genotype factors, with their target genes identified in silico. GO and KEGG enrichment analyses revealed the biological functions associated with DEM-target modules in stress adaptation processes, which could contribute to the phenotypic differences observed in two genotypes. The study provides the first evidence of the transgenerational effects of WH stress on N starvation response in durum wheat. Overall design: Analysis of small RNA transcriptome in eight biological pools (two genotypes by two parental treatment by two progeny treatment)