Mohanty Rashmi Prava, Buchheim Mark Alan, Anderson James, Levetin Estelle
Department of Biological Sciences, The University of Tulsa, Tulsa, Oklahoma, United States of America.
Environmental Allergy Assays, London, Ontario, Canada.
PLoS One. 2017 Mar 8;12(3):e0173465. doi: 10.1371/journal.pone.0173465. eCollection 2017.
Although considered rare, airborne pollen can be deposited far from its place of origin under a confluence of favorable conditions. Temporally anomalous records of Cupressacean pollen collected from January air samples in London, Ontario, Canada have been cited as a new case of long-distance transport. Data on pollination season implicated Juniperus ashei (mountain cedar), with populations in central Texas and south central Oklahoma, as the nearest source of the Cupressacean pollen in the Canadian air samples. This finding is of special significance given the allergenicity of mountain cedar pollen. While microscopy is used extensively to identify particles in the air spora, pollen from all members of the Cupressaceae, including Juniperus, are morphologically indistinguishable. Consequently, we implemented a molecular approach to characterize Juniperus pollen using PCR in order to test the long-distance transport hypothesis. Our PCR results using species-specific primers confirmed that the anomalous Cupressacean pollen collected in Canada was from J. ashei. Forward trajectory analysis from source areas in Texas and the Arbuckle Mountains in Oklahoma and backward trajectory analysis from the destination area near London, Ontario were completed using models implemented in HYSPLIT4 (Hybrid Single-Particle Lagrangian Integrated Trajectory). Results from these trajectory analyses strongly supported the conclusion that the J. ashei pollen detected in Canada had its origins in Texas or Oklahoma. The results from the molecular findings are significant as they provide a new method to confirm the long-distance transport of pollen that bears allergenic importance.
尽管空气中的花粉被认为很罕见，但在有利条件的共同作用下，它可以沉积在远离其起源地的地方。从加拿大安大略省伦敦市1月空气样本中收集到的柏科花粉的时间异常记录，被引为远距离传输的一个新案例。关于授粉季节的数据表明，得克萨斯州中部和俄克拉何马州中南部的种群中的杜松（山地雪松）是加拿大空气样本中柏科花粉的最接近来源。鉴于山地雪松花粉的致敏性，这一发现具有特殊意义。虽然显微镜被广泛用于识别空气中孢子中的颗粒，但包括杜松在内的柏科所有成员的花粉在形态上难以区分。因此，我们采用了一种分子方法，使用聚合酶链反应（PCR）来表征杜松花粉，以检验远距离传输假说。我们使用物种特异性引物的PCR结果证实，在加拿大收集到的异常柏科花粉来自阿氏杜松。利用HYSPLIT4（混合单粒子拉格朗日综合轨迹）模型完成了从得克萨斯州源区和俄克拉何马州阿尔巴克尔山脉的向前轨迹分析，以及从安大略省伦敦市附近目的地的向后轨迹分析。这些轨迹分析结果有力地支持了在加拿大检测到的阿氏杜松花源自得克萨斯州或俄克拉何马州的结论。分子研究结果具有重要意义，因为它们提供了一种新方法来证实具有致敏重要性的花粉的远距离传输。
