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Bainong sterility (BNS) is a thermo‐sensitive genic male sterile wheat line, characterised by anther fertility transformation in response to low temperature (LT) stress during meiosis, the failure of vacuole decomposition and the absence of starch accumulation in sterile bicellular pollen. Our study demonstrates that the late microspore (LM) stage marks the transition from the anther growth to anther maturation phase, characterised by the changes in anther structure, carbohydrate metabolism and the main transport pathway of sucrose (Suc). Fructan is a main storage polysaccharide in wheat anther, and its synthesis and remobilisation are crucial for anther development. Moreover, the process of pollen amylogenesis and the fate of the large vacuole in pollen are closely intertwined with fructan synthesis and remobilisation. LT disrupts the normal physiological metabolism of BNS anthers during meiosis, particularly affecting carbohydrate metabolism, thus determining the fate of male gametophytes and pollen abortion. Disruption of fructan synthesis and remobilisation regulation serves as a decisive event that results in anther abortion. Sterile pollen exhibits common traits of pollen starvation and impaired starch accumulation due to the inhibition of apoplastic transport starting from the LM stage, which is regulated by cell wall invertase TaIVR1 and Suc transporter TaSUT1. Summary statement: The manuscript provides new insight into the role of carbohydrate metabolism in regulating anther development and the molecular mechanisms underlying pollen abortion in a thermo‐sensitive genic male sterile winter wheat line under low temperature during meiosis. [ABSTRACT FROM AUTHOR]

Background: The adzuki bean is a typical short-day plant and an important grain crop that is widely used due to its high nutritional and medicinal value. The adzuki bean flowering time is affected by multiple environmental factors, particularly the photoperiod. Adjusting the day length can induce flower synchronization in adzuki bean and accelerate the breeding process. In this study, we used RNA sequencing analysis to determine the effects of different day lengths on gene expression and metabolic characteristics related to adzuki bean flowering time. Methods: 'Tangshan hong xiao dou' was used as the experimental material in this study and field experiments were conducted in 2022 using a randomized block design with three treatments: short-day induction periods of 5 d (SD-5d), 10 d (SD-10d), and 15 d (SD-15d). Results: A total of 5,939 differentially expressed genes (DEGs) were identified, of which 38.09% were up-regulated and 23.81% were down-regulated. Gene ontology enrichment analysis was performed on the target genes to identify common functions related to photosystems I and II. Kyoto Encyclopedia of Genes and Genomes enrichment analysis identified two pathways involved in the antenna protein and circadian rhythm. Furthermore, florescence was promoted by down-regulating genes in the circadian rhythm pathway through the blue light metabolic pathway; whereas, antenna proteins promoted flowering by enhancing the reception of light signals and accelerating electron transport. In these two metabolic pathways, the number of DEGs was the greatest between the SD-5d VS SD-15d groups. Real-time reverse transcription‒quantitative polymerase chain reaction analysis results of eight DEGs were consistent with the sequencing results. Thus, the sequencing results were accurate and reliable and eight genes were identified as candidates for the regulation of short-day induction at the adzuki bean seedling stage. Conclusions: Short-day induction was able to down-regulate the expression of genes related to flowering according to the circadian rhythm and up-regulate the expression of certain genes in the antenna protein pathway. The results provide a theoretical reference for the molecular mechanism of short-day induction and multi-level information for future functional studies to verify the key genes regulating adzuki bean flowering. [ABSTRACT FROM AUTHOR]

Summary: The cell wall is the major interface for arbuscular mycorrhizal (AM) symbiosis. However, the roles of cell wall proteins and cell wall synthesis in AM symbiosis remain unclear. We reported that a novel wall‐associated kinase 13 (GhWAK13) positively regulates AM symbiosis and negatively regulates Verticillium wilt resistance in cotton.GhWAK13 transcription was induced by AM symbiosis and Verticillium dahliae (VD) infection. GhWAK13 is located in the plasma membrane and expressed in the arbuscule‐containing cortical cells of mycorrhizal cotton roots.GhWAK13 silencing inhibited AM colonization and repressed gene expression of the mycorrhizal pathway. Moreover, GhWAK13 silencing improved Verticillium wilt resistance and triggered the expression of immunity genes. Therefore, GhWAK13 is considered an immune suppressor required for AM symbiosis and disease resistance. GhWAK7A, a positive regulator of Verticillium wilt resistance, was upregulated in GhWAK13‐silenced cotton plants. Silencing GhWAK7A improved AM symbiosis. Oligogalacturonides application also suppressed AM symbiosis. Finally, GhWAK13 negatively affected the cellulose content by regulating the transcription of cellulose synthase genes.The results of this study suggest that immunity suppresses AM symbiosis in cotton. GhWAK13 affects AM symbiosis by suppressing immune responses. See also the Commentary on this article by Giovanetti & Genre, 242: 1851–1853. [ABSTRACT FROM AUTHOR]