Morphological,anatomical structure and optimal light response model of <i>Bougainvillea spectabilis</i> leaves under NO₂ stress

PDF HTML阅读 XML下载 导出引用 引用提醒 NO2胁迫下三角梅叶片形态解剖结构和最优光响应模型研究 DOI: 10.5846/stxb202204261166 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学青年科学基金项目（32101582）；江苏省自然科学青年基金（BK20210613）；江苏省高等学校自然科学研究面上项目（21KJB220008） Morphological,anatomical structure and optimal light response model of Bougainvillea spectabilis leaves under NO2 stress Author: Affiliation: Fund Project: 摘要 | 图/表 访问统计 参考文献 相似文献 引证文献 资源附件 文章评论 摘要:植物的形态结构和光合作用能够反映植物对城市空气污染的响应特性。探究城市道路机动车尾气中的典型污染物NO2气体，对植物叶片的生理光合响应特性。以二年生三角梅（Bougainvillea spectabilis）幼苗为对象，利用智能化人工熏气室模拟熏气（NO2体积分数分别为0 μL/L （自然空气）、4 μL/L，8 μL/L，记作CK、T1、T2），观察NO2胁迫后三角梅的叶片形态、微观结构和光合特征。结果表明：（1）通过叶片形态观察发现，与CK相比，低浓度T1组叶片变化不明显，随着NO2气体胁迫浓度的增加，高浓度T2组叶片逐渐出现失水、叶表面有明显的水渍状或烧灼状黄色斑点。（2）通过叶片微观结构解剖发现，高浓度NO2胁迫后气孔皱缩程度增加，气孔开度减小；叶绿体结构变形，尤其是类囊体结构疏松，膨胀等变化。（3）叶片光合特性分析发现，T1和T2组的NO2胁迫导致光饱和点（LSP）和最大净光合速率（Pnmax）下降、光补偿点（LCP）增加，表观量子效率（AQE）和暗呼吸速率（Rd）在4种光响应模型中变化规律存在一定的差异性。（4）4种光响应模型中，CK组决定系数（R2）越高，均方根误差（RMSE）越低，精度最高，尤以叶子飘等机理模型为最优，拟合效果最好，其次是直角双曲线模型。研究结果表明三角梅可通过自身的形态变化、调整光合特征参数，较好地适应不同浓度的NO2，尤其是高浓度急性胁迫下，该研究结果有助于促进不同道路绿地三角梅的推广应用，对探究三角梅的景观效益和生态效益，揭示其对环境异质性的适应机制具有重要意义。 Abstract:Plant morphology photosynthesis can serve as indicators how well a plant will react to urban air pollution. The physiological photosynthetic NO2, characteristic contaminant in vehicle exhaust from roads, was studied this study. intelligent artificial fumigation chamber used simulate the biennial seedlings (NO2 volume fraction 0 (natural air), 4 μL/L, 8 labeled CK, T1, T2).After stress, we looked at leaf morphology, microstructure, traits B. spectabilis. findings revealed that:(1) It discovered that low concentration T1 group's underwent minimal alteration comparison CK. high T2 group gradually lost water gas stressed them, leaving either clear stains or cauterized yellow patches on surface. (2) Leaf microstructure study conditions extent stomatal shrinking increased openness reduced. Chloroplast changes, particularly loosening enlargement thylakoid structure.(3) characteristics groups decreased maximum net rate (Pnmax) saturation point (LSP), while increasing compensation (LCP). There were differences between four models terms apparent quantum efficiency (AQE) dark respiration (Rd). (4) Among models, CK had highest accuracy, lowest root mean square error, coefficient determination (R2) among four. Particularly, rectangular hyperbola comes second place drift mechanism best fitting performance.Our study's demonstrate may adapt varying concentrations, notably concentrations acute by changing its characteristics.The assist spread awareness use various road greenbelt is crucial understand spectabilis' ecological spatial advantages process adaptation order better environmental heterogeneity.