Feathertop Rhodes grass (Chloris virgata Sw.) is a summer growing grass weed that is invading farming land in southern Australia, being favoured by conservation farming systems and weed management using a narrow range of herbicides. Improved understanding of the biology of this species will be important for its effective management. A series of experiments on seed germination, dormancy release and emergence pattern were conducted under laboratory, glasshouse, and field conditions at Wagga Wagga Agricultural Institute. Seed of feathertop Rhodes grass exhibited post-harvest dormancy but germinated after a 3-month after-ripening period. Soil moisture was critical for the emergence of feathertop Rhodes grass in both a sandy loam and heavy clay soil. Higher emergence levels occurred in the sandy loam, but seedling survival was higher in the heavy clay soil. Seeds buried at shallower depths had a high probability of emergence and emerged within 1–3 days, with more than 70% of seed emerging within 7 days from burial at depths of 0- and 2-cm. Seed of feathertop Rhodes grass can germinate early in spring in southern NSW but compete poorly when emerging in an established cereal crop. In a fallow situation, there can be staggered emergence of feathertop Rhodes grass, triggered by the rainfall events. Our results indicate that feathertop Rhodes grass might not be a problem in cereal cropping in southern NSW. Effective management should focus on winter and summer fallows. Strategic cultivation could be a useful control tactic for feathertop Rhodes grass management. Exposure to either paraquat or glufosinate herbicides reduced seed viability, depending on the application timing. Our study provides important information on the growth, development, and seed biology of feathertop Rhodes grass that will contribute to the development of a more effective management program for this weed in southern Australia.

中文翻译：

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羽顶罗得草 （Chloris virgata Sw.） 的发芽生态学、出苗动力学和竞争：对有效控制策略的意义


羽顶罗德草 （Chloris virgata Sw.） 是一种夏季生长的禾本科杂草，正在入侵澳大利亚南部的农田，受到保护性农业系统和使用范围狭窄的除草剂的杂草管理的青睐。提高对该物种生物学的了解对于其有效管理非常重要。在 Wagga Wagga 农业研究所的实验室、温室和田间条件下进行了一系列关于种子发芽、休眠释放和出苗模式的实验。羽顶罗德草的种子在收获后表现出休眠状态，但在成熟后 3 个月后发芽。土壤水分对于沙质壤土和重粘土中羽顶罗德草的出现至关重要。沙质壤土的出苗水平较高，但重粘土中的幼苗存活率较高。埋藏在较浅深度的种子出现的可能性很高，并在 1-3 天内出现，超过 70% 的种子在 0 厘米和 2 厘米的深度埋藏后 7 天内出现。在新南威尔士州南部，羽顶罗德草的种子可以在早春发芽，但在成熟的谷物作物中发芽时竞争不佳。在休耕情况下，由降雨事件触发的羽顶罗德草可能会交错出现。我们的结果表明，羽顶罗德草在新南威尔士州南部的谷物种植中可能不是问题。有效的管理应侧重于冬季和夏季休耕。战略性培养可能是羽顶罗德草管理的有用控制策略。接触百草枯或草铵膦除草剂会降低种子的活力，具体取决于施用时间。 我们的研究提供了有关羽顶罗德草生长、发育和种子生物学的重要信息，这将有助于为澳大利亚南部的这种杂草制定更有效的管理计划。