Salinity is one of the most important factors limiting agricultural productivity. The positive effects of an inoculation with Bacillus subtilis HS5B5 on maize (Zea mays L.) seed germination and seedling growth under saline conditions were elucidated in this study. Maize plants were treated with four NaCl concentrations (0, 100, 200, and 300 mmol·L⁻¹) under hydroponic conditions and the plants inoculated with B. subtilis HS5B5 were compared with the non-inoculated plants in terms of key morphophysiological leaf and root traits. Maize seed germination and seedling growth were inhibited by NaCl stress. The inoculation with B. subtilis HS5B5 significantly increased the germination rate, germination potential, shoot length, and root length under NaCl stress conditions. Moreover, the plant height, biomass, root to shoot weight ratio, above-ground fresh weight, and below-ground fresh weight were higher for the inoculated maize seedlings than for the non-inoculated plants under saline conditions. Additionally, B. subtilis HS5B5 alleviated the salt-induced damage to maize by increasing the chlorophyll content, altering the abundance of osmoregulatory substances, and increasing antioxidant enzyme activities, while decreasing the malondialdehyde content. After the NaCl treatment, the Na⁺ content in the leaves and roots of maize plants inoculated with B. subtilis HS5B5 decreased significantly, while the K⁺ content increased. Thus, the inhibitory effect of NaCl stress on maize seed germination and seedling growth was mitigated by B. subtilis HS5B5, suggesting the utility of this microorganism for improving crop cultivation under saline conditions.

Against the backdrop of global climate change and the increasing frequency of extreme weather events, a central scientific question has emerged: how do plants adapt to such “pulsed” stressors? While traditional research has focused on immediate physiological responses and long-term genetic adaptation, this review introduces “ecological memory” as a novel integrative framework. It emphasizes the ability of plants to actively “record” past stress experiences through epigenetic mechanisms, thereby enhancing their adaptability to future adversities. This article systematically elucidates the molecular basis whereby abiotic stressors induce specific epigenetic modifications (e.g., DNA methylation and histone modifications) to form memories. It further discusses how such memories mediate physiological integration mechanisms, such as acclimation and priming-induced resistance at the individual level, and highlights potential pathways for transgenerational epigenetic memory transmission, which may accelerate population-level adaptive evolution. Finally, we evaluate the applications of the ecological memory concept in predicting species distribution, enhancing ecosystem resilience, and guiding the design of “climate smart” crops, aiming to shift the research paradigm from static tolerance studies to dynamic memory and adaptation frameworks.

The low availability of phosphorus (P) in soil has become a critical factor limiting crop growth and agricultural productivity. This study aimed to isolate and evaluate a bacterial strain with high phosphate-solubilizing capacity to improve soil phosphorus utilization and promote crop growth. A phosphate-solubilizing bacterium, designated as YS-13, was isolated from farmland soil in Henan Province, China, and identified as Brevibacillus laterosporus based on morphological characteristics, physiological and biochemical traits, and 16S rDNA sequence analysis. Qualitative assessment using plate assays showed that strain YS-13 formed a prominent phosphate solubilization zone on organic and inorganic phosphorus media containing lecithin and calcium phosphate, with D/d ratios of 2.28 and 1.57, respectively. Quantitative evaluation using the molybdenum–antimony colorimetric method revealed soluble phosphorus concentrations of 21.24, 6.67, 11.73, and 17.05 mg·L⁻¹ when lecithin, ferric phosphate, calcium phosphate, and calcium phytate were used as phosphorus sources, respectively. The fermentation conditions for YS-13 were optimized through single-factor experiments combined with response surface methodology, using viable cell count as the response variable. The optimal conditions were determined as 34 °C, 8% inoculum volume, initial pH of 7.55, 48 h incubation, 5 g L⁻¹ NaCl, 8.96 g L⁻¹ glucose, and 8.86 g L⁻¹ peptone, under which the viable cell count reached 6.29 × 10⁸ CFU mL⁻¹, consistent with the predicted value (98.33%, p < 0.05). The plant growth-promoting effect of YS-13 was further validated through a pot experiment using Triticum aestivum cv. Jinchun 6. Growth parameters, including plant height, fresh biomass, root length, root surface area, root volume, and phosphorus content in roots and stems, were measured. The results demonstrated that YS-13 significantly enhanced wheat growth, with a positive correlation between bacterial concentration and growth indicators, although the growth-promoting effect plateaued at higher concentrations. This study successfully identified a high-efficiency phosphate-solubilizing strain, YS-13, and established optimal culture conditions and bioassay validation, laying a foundation for its potential application as a microbial inoculant and providing theoretical and technical support for reducing phosphorus fertilizer inputs and advancing sustainable agriculture.