Institute of Quality Safety and Standards of Agricultural Products Research, Jiangxi Academy of Agricultural Sciences, Nanchang, China; National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China; Key Laboratory of Grain Crop Genetic Resources Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Shanghai, China; Shanghai Agrobiological Gene Center, Shanghai, China.
National Key Laboratory of Crop Genetic Improvement, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
Plant Physiol Biochem. 2024 Nov;216:109145. doi: 10.1016/j.plaphy.2024.109145. Epub 2024 Sep 22.
Drought hampers agricultural production by constraining crop growth and development. Nevertheless, there has been limited exploration regarding the effect of biochar coating in enhancing seed germination under drought conditions and understanding its underlying mechanisms. To fill this gap and clarify the pathway to drought resistance, the current research investigated the protective effectiveness of BC on seedling establishment and subsequent growth of rice under drought conditions. Results showed that BC notably elevated emergence rate (5.5%), shoot length (27.4%), root length (33.4%), plant height (19.6/10.3%), leaf area (69.8/71.7%), and plant biomass (85.7/67.9%) after 15/30 days under drought conditions compared to the control. Biochar coating facilitated the maintenance of a stable chloroplast structure, reduced chlorophyll degradation, and sustained cell expansion. This contributed to the improvement of stomatal characteristics on both adaxial and abaxial leaf surfaces during drought stress, encompassing enhancements in stomatal density and aperture. The preservation of stomatal opening led to an increased photosynthetic capacity, thereby fostering elevated photosynthetic activity and heightened plant biomass under stressful conditions. Simultaneously, BC treatment significantly diminished the production of reactive oxygen species, preserved cell membrane integrity, and augmented the accumulation of osmotic protectants. These outcomes signify that biochar coating mitigates the deleterious impacts of drought stress on photosynthesis, stomatal aperture, chloroplast ultrastructure, osmotic regulation, and redox homeostasis in plants through specific water and nutrient regulation. Consequently, this enhances the tolerance and growth of rice under drought stress.
干旱通过限制作物生长和发育来阻碍农业生产。然而，对于生物炭涂层在增强干旱条件下种子萌发方面的作用及其潜在机制的研究还很有限。为了填补这一空白并阐明抗旱途径，本研究调查了 BC 在干旱条件下对水稻幼苗建立和随后生长的保护效果。结果表明，与对照相比，BC 在干旱条件下 15/30 天后显著提高了发芽率（5.5%）、苗高（27.4%）、根长（33.4%）、株高（19.6/10.3%）、叶面积（69.8/71.7%）和植物生物量（85.7/67.9%）。生物炭涂层有助于维持叶绿体结构的稳定，减少叶绿素的降解，维持细胞的扩张。这有助于在干旱胁迫下改善正反两面叶片的气孔特征，包括增加气孔密度和孔径。气孔开度的保持导致光合作用能力提高，从而在胁迫条件下促进光合作用活性和植物生物量的增加。同时，BC 处理显著减少了活性氧的产生，保持了细胞膜的完整性，并增加了渗透保护剂的积累。这些结果表明，生物炭涂层通过特定的水和养分调节，减轻了干旱胁迫对植物光合作用、气孔开度、叶绿体超微结构、渗透调节和氧化还原平衡的有害影响。因此，它增强了水稻在干旱胁迫下的耐受性和生长。
