The flavor of cigar tobacco leaf determines the quality of finished cigar tobacco, and the enhancement of flavor generally relies on microbial fermentation. In this paper, the correlation between the dominant microorganisms and the main flavor substances of cigar tobacco leaves during fermentation and the correlation between the two were investigated to reveal the correlation between microorganisms and flavor and the metabolic pathways of microorganisms affecting the flavor substances. During the fermentation process, the main flavors of cigar tobacco leaves were sweet, light and grassy, with hexanal, 2,6-dimethylpyridine, nonanal, phenylacetaldehyde, naphthalene, and methyl benzoate as the main constituents, and the key microorganisms Haloferax mediterranei, Haloterrigena limicola, Candidatus Thorarchaeota archaeon SMTZ-45, the genera Methyloversatilis, Sphingomonas, Thauera, Pseudomonas, Penicillium, and Aspergillus. Correlation analysis revealed that fungi were negatively correlated with the main aroma and inhibited the main flavor substances, while bacteria were positively correlated with Benzoic acid, methyl ester in the main flavor substances, which was conducive to the accumulation of green aroma. Functional analysis revealed that the dominant bacterial population was producing aroma by metabolizing glycoside hydrolases and glycosyltransferases, performing amino acid metabolism, carbohydrate metabolism and film transport metabolism. The present study showed that the bacterial and fungal dominant microorganisms during the fermentation of cigar tobacco were influencing the production and degradation of the main flavor substances through the enzyme metabolism by the occurrence of the Merad reaction.

Salinity stands as a significant environmental stressor, severely impacting crop productivity. Plants exposed to salt stress undergo physiological alterations that influence their growth and development. Meanwhile, plants have also evolved mechanisms to endure the detrimental effects of salinity-induced salt stress. Within plants, Calcineurin B-like (CBL) proteins act as vital Ca²⁺ sensors, binding to Ca²⁺ and subsequently transmitting signals to downstream response pathways. CBLs engage with CBL-interacting protein kinases (CIPKs), forming complexes that regulate a multitude of plant growth and developmental processes, notably ion homeostasis in response to salinity conditions. This review introduces the repercussions of salt stress, including osmotic stress, diminished photosynthesis, and oxidative damage. It also explores how CBLs modulate the response to salt stress in plants, outlining the functions of the CBL-CIPK modules involved. Comprehending the mechanisms through which CBL proteins mediate salt tolerance can accelerate the development of cultivars resistant to salinity.

Plant growth and development are driven by intricate processes, with the cell membrane serving as a crucial interface between cells and their external environment. Maintaining balance and signal transduction across the cell membrane is essential for cellular stability and a host of life processes. Ion channels play a critical role in regulating intracellular ion concentrations and potentials. Among these, K⁺ channels on plant cell membranes are of paramount importance. The research of Shaker K⁺ channels has become a paradigm in the study of plant ion channels. This study offers a comprehensive overview of advancements in Shaker K⁺ channels, including insights into protein structure, function, regulatory mechanisms, and research techniques. Investigating Shaker K⁺ channels has enhanced our understanding of the regulatory mechanisms governing ion absorption and transport in plant cells. This knowledge offers invaluable guidance for enhancing crop yields and improving resistance to environmental stressors. Moreover, an extensive review of research methodologies in Shaker K⁺ channel studies provides essential reference solutions for researchers, promoting further advancements in ion channel research.

Introduction: To study the composition and succession of bacterial and fungal communities during the fermentation of cigar filler leaves with varying initial water contents, high-throughput sequencing technology was used to sequence the bacterial 16SrRNA genes and fungal ITS1 genes from cigar tobacco leaf samples. This was followed by analyses of microbial α-diversity, microbial community structure, and bacterial function prediction based on the sequencing data.Results: The diversity and richness of microbial communities decreased over time during fermentation under different water content conditions. Among the 18 cigar filler leaf samples, the predominant phyla identified were Proteobacteria, Firmicutes, Actinobacteria, Ascomycota, and Basidiomycota, with the leading genera being Staphylococcus, Sphingomonas, Methylobacterium-Methylorubrum, Pseudomonas, and Humicola. Functional predictions for the bacteria revealed their primary involvement in carbohydrate, lipid, and amino acid metabolism.Conclusion: The initial water content of cigar tobacco leaves influenced the structure and relative abundance of microbial communities during fermentation. While the microbial community exhibited a similar structural composition, there were notable differences in relative abundance. The functional prediction results from PICRUSt indicated that the differences in predicted functional species among samples were minimal, whereas the variations in the abundance of functional species were more pronounced across different fermentation stages and initial water contents.

In this study, the CTLs from Hainan, China, were used, the aroma profiles of CTLs from five years (2017–2021) and three varieties [Hainan2 (HN2), Jianheng3 (JH3), and Guyin4 (GY4)] were analyzed, and the microbial communities of these CTLs and the relation with aroma constituents were explored. Results revealed the contents of total aroma constituents (3.55–7.67 mg/kg), esters (47.4–824 μg/kg), alcohols (123–561 μg/kg), aldehydes (51.4–97.1 μg/kg), and nitrogen heterocycles (1.86–4.25 mg/kg), firstly increased and subsequently declined with the increase of years, whereas ketones (1.07–3.56 mg/kg) exhibited an inverse trend. Among the different varieties, the highest aldehyde (142 μg/kg) content was observed in JH3, while the highest total aroma constituents, acids, ketones, and nitrogen heterocycles were found in GY4, reaching 10.5, 0.604, 1.86, 6.43 mg/kg, respectively. Furthermore, the bacterial communities of CTLs from different years exhibited discernible succession with increasing years. The abundances of Staphylococcus (3.03–47.5%) and Sphingomonas (1.18–10.2%) first increased and then decreased, whereas Pseudomonas (1.63–11.5%), Ralstonia (0.669–20.2%), and Pantoea (6.07–10.5%) exhibited the opposite trend, and Aspergillus and Cladosporium with total abundances of 90.2–94.2% were predominant in all years. The dominant bacteria and fungi of CTLs from different varieties were identified as Staphylococcus (15.0–81.1%) and Aspergillus (45.6–85.0%), respectively. However, the dominant microbial abundances in JH3 were significantly lower than those in HN2 and GY4, while other microorganism abundances were increased. Partial least square-regression analysis demonstrated that Paracoccus, Staphylococcus, Aerococcus, Pantoea, Methylobacterium-Methylorubrum, and Bacillus of CTLs from different years were associated with aroma constituents. Graphical Abstract