Navua sedge [Cyperus aromaticus (Ridley) Mattf. & Kük.] is an aggressive perennial sedge native to equatorial Africa that has become problematic in many Pacific islands and wet, tropical Queensland, Australia. It has had a significant impact on the livestock-grazing industry, sugarcane (Saccharum officinarum L.) and banana (Musa acuminata Colla) plantations, and various other ecosystems. A laboratory-based research investigation was conducted to understand germination and emergence requirements under various environmental conditions of three geographically varied populations sourced from South Johnstone (SJ), Mackay (M) and Nyleta Creek (NC) in Queensland. Germination was identified to be stimulated by light, with no germination recorded under darkness. Populations SJ and NC had optimal germination at alternating temperatures of 25/15, 30/20, and 35/25 C, whereas population M had optimal germination at 25/15 and 30/20 C. All populations recorded greater than 85% germination at all pH levels tested. Seeds of population SJ were more sensitive to salinity compared with populations M and NC, with SJ showing no germination at 100 mM, whereas populations M and NC had 23% and 9% germination, respectively. An inverse relationship was observed between osmotic potential and germination, with no germination recorded at osmotic potentials below −0.8 MPa in any population, indicating moisture availability is a critical requirement for germination. Exposing seeds to 120 C radiant heat completely inhibited germination in populations M and NC, whereas 3% of population SJ germinated following a 180-s exposure at 120 C. Seedling emergence decreased as planting depth increased. Emergence was greatest for seeds on the soil surface or at 0.5-cm burial depth, consistent with germination being stimulated by light. Knowledge of these biological characteristics of C. aromaticus seed germination will assist in investigation of suitable control actions for this species, particularly in the early stage of its invasion into new areas, and will contribute to significant reduction in the soil seedbank.

中文翻译：

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Navua 莎草（香附）三个种群的萌发生物学

Navua莎草[香附（雷德利）马特夫。& Kük.] 是一种具有侵略性的多年生莎草，原产于赤道非洲，在许多太平洋岛屿和潮湿的热带昆士兰州，澳大利亚已成为问题。它对畜牧业、甘蔗产生了重大影响（甘蔗L.) 和香蕉 (苦瓜Colla) 种植园和其他各种生态系统。进行了一项基于实验室的研究调查，以了解来自昆士兰州南约翰斯通 (SJ)、麦凯 (M) 和 Nyleta Creek (NC) 的三个地理不同种群在各种环境条件下的发芽和出苗要求。发芽被确定为受光刺激，在黑暗中没有记录到发芽。种群 SJ 和 NC 在 25/15、30/20 和 35/25 C 的交替温度下具有最佳发芽率，而种群 M 在 25/15 和 30/20 C 下具有最佳发芽率。所有种群在测试的所有 pH 值水平。与群体 M 和 NC 相比，群体 SJ 的种子对盐度更敏感，SJ 在 100 mM 时没有发芽，而种群 M 和 NC 分别有 23% 和 9% 的发芽率。在渗透势和发芽之间观察到反比关系，在任何种群中渗透势低于 -0.8 MPa 时没有记录到发芽，这表明水分可用性是发芽的关键要求。将种子暴露于 120 C 辐射热完全抑制了 M 和 NC 种群的发芽，而 3% 的 SJ 种群在 120 C 暴露 180 秒后发芽。随着种植深度的增加，出苗率下降。种子在土壤表面或 0.5 厘米埋深处的出苗率最高，这与受光刺激发芽一致。了解这些生物特征 在任何种群中，在渗透势低于 -0.8 MPa 时没有记录到发芽，这表明水分可用性是发芽的关键要求。将种子暴露于 120 C 辐射热完全抑制了 M 和 NC 种群的发芽，而 3% 的 SJ 种群在 120 C 暴露 180 秒后发芽。随着种植深度的增加，出苗率下降。种子在土壤表面或 0.5 厘米埋深处的出苗率最高，这与受光刺激发芽一致。了解这些生物特征 在任何种群中，在渗透势低于 -0.8 MPa 时没有记录到发芽，这表明水分可用性是发芽的关键要求。将种子暴露于 120 C 辐射热完全抑制了 M 和 NC 种群的发芽，而 3% 的 SJ 种群在 120 C 暴露 180 秒后发芽。随着种植深度的增加，出苗率下降。种子在土壤表面或 0.5 厘米埋深处的出苗率最高，这与受光刺激发芽一致。了解这些生物特征 而 3% 的 SJ 种群在 120 摄氏度暴露 180 秒后发芽。随着种植深度的增加，出苗率下降。种子在土壤表面或 0.5 厘米埋深处的出苗率最高，这与受光刺激发芽一致。了解这些生物特征 而 3% 的 SJ 种群在 120 摄氏度暴露 180 秒后发芽。随着种植深度的增加，出苗率下降。种子在土壤表面或 0.5 厘米埋深处的出苗率最高，这与受光刺激发芽一致。了解这些生物特征C. 芳香种子萌发将有助于调查对该物种的适当控制措施，特别是在其入侵新地区的早期阶段，并将有助于显着减少土壤种子库。