In North American wetlands, two cattail species -native Typha latifolia and exotic T. angustifolia- hybridize generating T. x glauca. Typha angustifolia and the hybrid spread invasively, negatively affecting wetlands. Due to high trait variability and hybridization, Typha species are difficult to identify morphologically. Building on previous work that relied on microsatellite markers to differentiate Typha species (including hybrids, parental backcrosses, and advanced-generation hybrids) in southern Canada and in the US upper Midwest and northeast, our goals were to 1) estimate relative frequencies of parental species in additional Midwestern cattail populations, and 2) quantify their hybridization. We also assessed level of agreement between morphological identification based on leaf width and gap between inflorescences and molecular identification. Using 6 microsatellites markers (4 used previously in other populations and 2 novel ones), we identified ~25% of the samples as native T. latifolia, while ~6% were exotic T. angustifolia. Furthermore, 19% of the samples were first-generation hybrids (T. x glauca) and 50% were advanced-generation hybrids, with backcrosses to native T. latifolia being almost twice as high as those to exotic T. angustifolia, rates that are much larger than previously reported. Agreement between morphological and molecular identification was lower than expected highlighting the fact that these morphological traits can be misleading when used alone in cattail identification. We caution that the seemingly asymmetric hybridization towards the native Typha latifolia could potentially lead to its extinction in the Midwest. Cattail management may thus require efforts to preserve the native cattail through seed banking and/or other approaches.

在北美湿地中，两种香蒲物种-香蒲（Typha latifolia）和奇异的T. angustifolia-杂交产生了T. x glauca。香蒲和杂种侵入地传播，对湿地产生负面影响。由于高性状变异性和杂交性，香蒲种类很难在形态上鉴定。在先前依靠微卫星标记物区分香蒲的工作的基础上在加拿大南部和美国中西部和东北部上游的物种（包括杂种，亲本回交和先进的杂种），我们的目标是1）估计其他中西部香蒲种群中亲本物种的相对频率，以及2）量化它们的杂交。我们还评估了基于叶宽和花序之间的间隙与分子鉴定之间的形态学鉴定之间的一致性水平。使用6个微卫星标记（之前在其他种群中使用了4个，在其他种群中使用了2个新标记），我们确定了约25％的样品为天然紫叶苜蓿，而约6％的样品为奇异的T. angustifolia。此外，有19％的样本是第一代杂种（T. x glauca）和50％是先进的杂交种，与本地T. latifolia的回交率几乎是与异国T. angustifolia的回交率的两倍，该比率比以前报道的要大得多。形态和分子鉴定之间的一致性低于预期，突出了以下事实：这些形态特征单独用于香蒲鉴定时可能会产生误导。我们告诫，与本地香蒲的不对称杂交可能会导致其在中西部的灭绝。香蒲管理因此可能需要通过种子库和/或其他方法来努力保存天然香蒲。