Gray mold is a disease that often occurs in postharvest tomato fruits, leading to a significant decline in the fruits’ quality. In production, pesticides are mostly used to control gray mold, which negatively affect both the environment and food safety. The purpose of this article is to study the effects of linalool fumigation on controlling gray mold in tomato fruits and to further investigate the mechanism of linalool function, so as to provide technical support and a theoretical basis for the application of linalool in the green control of tomato gray mold. The results of the in vitro experiments showed that linalool fumigation had a strong inhibitory effect on the mycelial growth of Botrytis cinerea and that the fumigation of linalool inhibited the expansion of pathogens on tomato fruits. The disease index of tomato fruits in the linalool treatment was always lower than that of the control within 72 h after inoculation with Botrytis cinerea; at the end of experiment, the disease index of the control reached 100.0, which was only 8.0 with the 30 μL/L linalool treatment. Linalool fumigation increased the antioxidant capacity of the tomato fruits under Botrytis cinerea infection through regulating activities of SOD, POD and CAT as well as the ascorbic acid (AsA) content, which could be responsible for the lower malondialdehyde (MDA) accumulation. Linalool fumigation increased the activities of polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL) in tomato fruits, indicating that secondary metabolism was involved in the function of linalool in the regulation of tomato fruit resistance to pathogens. As the main enzymes related to cell structure, polygalacturonase (PG), cellulase (CL) and β-galactosidase (β-GAL) were inhibited by linalool, which could protect cell wall structures from damage, and strengthened the mechanical barrier against pathogen access to fruit flesh.

Tomato (Jinglu 6335) was selected for assessing the impact of varying fertilizer (F:N-P₂O₅-K₂O) and aeration rates on crop quality, as well as water and fertilizer utilization efficiency during the cyclic aeration subsurface drip irrigation process. Four aeration treatments (O1, O2, O3, and S, representing aeration ratios of 16.25%, 14.58%, 11.79%, and non-aerated treatment, respectively) and three fertilizer applications (F1: 240–120–150 kg/hm², F2: 180–90–112.5 kg/hm², F3: 120–60–75 kg/hm²) were compared in a total of 12 treatments in this study. This study revealed that cyclic aerated drip irrigation improved the fruit quality. The aerated treatment resulted in increased accumulation of nitrogen, phosphorus, and potassium, with the level of aeration positively correlating with the increase in nutrient accumulation, reaching the highest values in the high aeration irrigation treatment. The highest nitrogen, phosphorus, potassium, and water use efficiency occurred under the medium fertilizer with high aeration treatment. The maximum partial productivity of the fertilizer occurred under the low fertilizer with high aeration treatment, while the minimum occurred in the high fertilizer with non-aerated treatment. Taking all factors into consideration, the high-aeration and medium-fertilizer treatment was the most effective combination for greenhouse tomatoes under the conditions in this experiment.

High-mobility group B (HMGB) proteins are a class of non-histone proteins associated with eukaryotic chromatin and are known to regulate a variety of biological processes in plants. However, the functions of HMGB genes in tomato (Solanum lycopersicum) remain largely unexplored. Here, we identified 11 members of the HMGB family in tomato using BLAST. We employed genome-wide identification, gene structure analysis, domain conservation analysis, cis-acting element analysis, collinearity analysis, and qRT-PCR-based expression analysis to study these 11 genes. These genes were categorized into four groups based on their unique protein domain structures. Despite their structural diversity, all members contain the HMG-box domain, a characteristic feature of the HMG superfamily. Syntenic analysis suggested that tomato SlHMGBs have close evolutionary relationships with their homologs in other dicots. The promoter regions of SlHMGBs are enriched with numerous cis-elements related to plant growth and development, phytohormone responsiveness, and stress responsiveness. Furthermore, SlHMGB members exhibited distinct tissue-specific expression profiles, suggesting their potential roles in regulating various aspects of plant growth and development. Most SlHMGB genes respond to a variety of abiotic stresses, including salt, drought, heat, and cold. For instance, SlHMGB2 and SlHMGB4 showed positive responses to salt, drought, and cold stresses. SlHMGB1, SlHMGB3, and SlHMGB8 were involved in responses to two types of stress: SlHMGB1 responded to drought and heat, while SlHMGB3 and SlHMGB8 responded to salt and heat. SlHMGB6 and SlHMGB11 were solely regulated by drought and heat stress, respectively. Under various treatment conditions, the number of up-regulated genes significantly outnumbered the down-regulated genes, implying that the SlHMGB family may play a crucial role in mitigating abiotic stress in tomato. These findings lay a foundation for further dissecting the precise roles of SlHMGB genes.

AINTEGUMENTA-LIKE (AIL) genes encode key transcriptional regulators governing plant growth. However, little is known of CsAIL genes in cucumber (Cucumis sativus L.). Here, six CsAIL genes in the cucumber genome were identified. Bioinformatic analyses revealed high evolutionary conservation of gene structures, protein domains, and motifs among CsAIL members. Expression profiling revealed tissue-specific patterns of CsAILs, hinting at their functional diversification in cucumber growth and development. Notably, CsAIL1 exhibited higher expression levels in ovaries, fruit spines, and seeds, implying its specialized role in these tissues, whereas no functions of AIL1 homologs were reported in other plant species. CsAIL members were also involved in abiotic stress responses, as evidenced by altered expression patterns under salt treatment. Additionally, CsAIL1 protein was localized in the nucleus and was predicted to interact with the ethylene response factor CsERF13. These findings provide a foundational understanding of the CsAIL gene family and contribute valuable insights towards the functional characterization of CsAIL genes in cucumber.

Salt stress limits plant growth and development of tomato (Solanum lycopersicum). S-adenosyl methionine synthetase (SAMS) plays a pivotal role in response to salt stress in plants, however, its mechanism for regulating carbon and nitrogen metabolism in this process is not fully understood. Herein, we found that SlSAMS1, a SAMS homologous gene in tomato, enhances salt tolerance throughout the entire lifecycle of tomato plants. Salt stress inhibits carbon and nitrogen metabolism in tomato plants, while overexpression of the SlSAMS1 gene maintains high levels of energy metabolism, as evidenced by increased nitrogen contents, sugar contents, and enzyme activities related to carbon and nitrogen metabolism during salt stress, thus ensuring better growth and development under salt stress in tomato.