Aquatic plants live in anoxic sediments that favor formation of hydrogen sulfide, a known phytotoxin. We investigated how the phenology of reproductive life stages of wild rice (Zizania palustris Poaceae), an annual aquatic graminoid, is influenced by rooting zone sulfur geochemistry in response to elevated sulfate and sulfide. In addition, we characterized how redox conditions in the rooting zone change throughout reproduction to determine if they are tied to plant life stage. The redox conditions in sediment decreased just prior to flowering, and again just prior to seed production for all plants, allowing sulfide to accumulate at the root surface of sulfate-amended plants. Plants exposed to sulfide initiated seed production later than unamended plants. Sulfide appears to slow plant development in a way that gives the plant less time to allocate nutrients to seeds before senescence. The impact of sulfide in delaying reproductive life stages of wild rice and changing seasonal rooting zone biogeochemistry could extend to other plant species and additional chemical species that change mobility with redox potential, such as phosphate, manganese, mercury, and other metals.

水生植物生活在缺氧沉积物中，有利于形成硫化氢（一种已知的植物毒素）。我们调查了野生稻（Zizania palustris）的生殖生命阶段的物候禾本科（Poaceae），一种一年生的水生类蠕虫，受硫酸根和硫化物升高的影响，受生根区硫地球化学的影响。此外，我们表征了生根区中的氧化还原条件在整个繁殖过程中如何变化，以确定它们是否与植物生命阶段有关。对于所有植物而言，沉积物中的氧化还原条件在开花前和种子生产前均下降，从而使硫化物积聚在硫酸盐改良的植物的根表面。暴露于硫化物的植物比未改良的植物更晚开始种子生产。硫化物似乎以某种方式减慢了植物的生长，使植物在衰老前减少了将营养分配给种子的时间。