Physiological and Proteomic Analyses Indicate Delayed Sowing Improves Photosynthetic Capacity in Wheat Flag Leaves Under Heat Stress

Transcriptomic and Phenotypic Analyses Reveal the Molecular Mechanism of Dwarfing in Tetraploid Robinia pseudoacacia L

Polyploid breeding techniques aid in the cultivation of new forestry cultivars, thus expanding the suite of strategies for the improvement of arboreal traits and innovation within the field of forestry. Compared to diploid Robinia pseudoacacia L. (black locust) 'D26-5①' (2×), its dwarfed homologous tetraploid 'D26-5②' (4×) variety has better application prospects in garden vegetation guardrails and urban landscape. However, the molecular mechanism of the generation and growth of this dwarf variety is still unclear. Here, plant growth and development as well as histological differences between the diploid and its autotetraploid were investigated. Levels of endogenous hormones at three different developmental stages (20, 40, and 70 days) of 2× and homologous 4× tissue culture plantlets were assessed, and it was found that the brassinosteroid (BR) contents of the former were significantly higher than the latter. Transcriptome sequencing data analysis of 2× and homologous 4× showed that differentially expressed genes (DEGs) were significantly enriched in plant hormone synthesis and signal transduction, sugar and starch metabolism, and the plant circadian rhythm pathway, which are closely related to plant growth and development. Therefore, these biological pathways may be important regulatory pathways leading to dwarfism and slow growth in tetraploids. Additionally, utilizing weighted gene coexpression network analysis (WGCNA), we identified three crucial differentially expressed genes (DEGs)-PRR5, CYP450, and SPA1-that potentially underlie the observed ploidy variation. This study provides a new reference for the molecular mechanism of dwarfism in dwarfed autotetraploid black locusts. Collectively, our results of metabolite analysis and comparative transcriptomics confirm that plant hormone signaling and the circadian rhythm pathway result in dwarfism in black locusts.

iTRAQ-Based Quantitative Proteomics Unveils Protein Dynamics in the Root of Solanum melongena L. under Waterlogging Stress Conditions

Waterlogging poses significant abiotic stress that endangers the survival of plants, including crops. In response, plants dramatically change their physiology to enhance their tolerance to waterlogging, such as proteome reconfiguration. Here, we utilized isobaric tags for the relative and absolute quantitation (iTRAQ)-based protein labeling technique to examine the proteomic changes induced by waterlogging in the roots of Solanum melongena L., a solanaceous plant. The plants were subjected to 6, 12, and 24 h of waterlogging stress at the flowering stage. Of the 4074 identified proteins, compared to the control, the abundance of the proteins increased and decreased in 165 and 78 proteins, respectively, in 6 h of treatments; 219 and 89 proteins, respectively, in 12 h of treatments; and 126 and 127 proteins, respectively, in 24 h of treatments. The majority of these differentially regulated proteins participated in processes such as energy metabolism, amino acid biosynthesis, signal transduction, and nitrogen metabolism. Fructose-bisphosphate aldolase and three alcohol dehydrogenase genes, in particular, were up- or down-regulated in waterlogging-treated Solanum melongena roots, suggesting that some proteins related to anaerobic metabolism (glycolysis and fermentation) may play vital roles in protecting its roots from waterlogging stress to enable long-term survival. Overall, this research not only offers a comprehensive dataset of protein alterations in waterlogged Solanum melongena roots but also insights into the mechanisms by which solanaceous plants adapt to waterlogging stress.