Agroenergy Research Group, Department of Agricultural Production. School of Agricultural, Food and Biosystems Engineering, Universidad Politecnica de Madrid (UPM), Avenue Complutense s/n, 28040, Madrid, Spain.
Department of Applied Mathematics. School of Agricultural, Food and Biosystems Engineering, Universidad Politecnica de Madrid (UPM), Avenue Complutense s/n, 28040, Madrid, Spain.
BMC Plant Biol. 2020 Aug 17;20(1):377. doi: 10.1186/s12870-020-02573-3.
Cattail (Typha domingensis Pers.) is a perennial emergent plant which is used in Green Floating Filters (GFFs), one of the most innovative systems of wastewater treatment to bioremediate eutrophic waters and produce biomass as biofuel feedstocks. The establishment of cattails in GFFs depends on the seed germination and plant responses under conditions of a new habitat. This study analysed the germination responses of four different populations of cattails through a thermal time model to know their basic parameters of germination and which population would be more adapted to the conditions tested.
Seeds from the Badajoz (Ba), Cuenca (Cu), Madrid (Ma), Seville (Se) and Toledo (To) populations were exposed to different thermal regimes (constant, and alternating temperatures between 15 and 30 °C) and different darkness treatments (between 0 and 20 days with 24 h dark photoperiod, then exposed to light with 12 h light/dark photoperiod) to determine the parameters of the thermal model from germination levels in each treatment. To population was used to validate the thermal time parameters of other populations. Regardless of the other parameters, no germination occurred in total darkness. The mean value of base temperature (T) was 16.4 ± 0.2 °C in all treatments. Optimum temperature (T) values in Ma and Ba were 25 °C, and those in Cu and Se were 22.5 °C. The germination response decreased when the temperature approached T and increased when it was close to T. In comparison to alternating temperatures, constant temperatures had the highest germination response and lowest thermal time (θ(50)). Darkness treatments had a direct relationship with θ(50). The population origin also affected seed germination; Cu had the highest values of T and germination response but had a lower θ(50), which coincides with the lowest mean ambient temperatures.
According to these results, the germination response of cattails was high in all populations under optimal conditions but was affected to a greater or lesser extent depending on thermal regimes, darkness treatments, and populations. The thermal time model allowed us to determine that T was between 22.5-25 °C and that Cu is the best population regarding the germination response under the conditions tested.
香蒲（Typha domingensis Pers.）是一种多年生挺水植物，用于绿色浮床（GFF）中，这是一种最具创新性的废水处理系统之一，可用于生物修复富营养化水体并生产生物燃料原料的生物质。香蒲在 GFF 中的建立取决于在新栖息地条件下的种子萌发和植物响应。本研究通过热时间模型分析了来自四个不同种群的香蒲种子的萌发响应，以了解它们的基本萌发参数，以及哪个种群更适应所测试的条件。
来自巴达霍斯（Ba）、昆卡（Cu）、马德里（Ma）、塞维利亚（Se）和托莱多（To）种群的种子暴露于不同的热环境（恒温，以及在 15 和 30°C 之间交替的温度）和不同的黑暗处理（在 24 小时黑暗光周期下 0 到 20 天，然后暴露于 12 小时光照/黑暗光周期的光下），以确定每个处理的萌发水平的热模型参数。To 种群用于验证其他种群的热时间参数。无论其他参数如何，在完全黑暗下都没有发生萌发。所有处理中基础温度（T）的平均值为 16.4±0.2°C。Ma 和 Ba 中的最适温度（T）值为 25°C，Cu 和 Se 中的最适温度为 22.5°C。当温度接近 T 时，萌发响应降低，当接近 T 时，萌发响应增加。与交替温度相比，恒温具有最高的萌发响应和最低的热时间（θ（50））。黑暗处理与 θ（50）直接相关。种群起源也影响种子萌发；Cu 具有最高的 T 和萌发响应值，但 θ（50）较低，这与最低的环境平均温度相对应。
根据这些结果，在最佳条件下，所有种群的香蒲种子萌发反应都很高，但根据热环境、黑暗处理和种群的不同，受到不同程度的影响。热时间模型使我们能够确定 T 在 22.5-25°C 之间，并且 Cu 是在测试条件下具有最佳萌发响应的最佳种群。
