A better understanding of weed seed production is a key element for any long‐term management allowing some weeds to shed seeds. The challenge with measuring seed production in weeds is the large effort required in terms of time and labour. For the weed species Echinochloa crus‐galli, it was tested whether the number of seeds per panicle dry weight or per panicle length can be used to estimate seed production. Experiments were conducted in three maize fields in north‐eastern Germany. The effect of factors that could influence this relationship, such as the time of seedling emergence, the density of E. crus‐galli, the control intensity of other weeds, seed predation and field, was included. A few days before maize harvest, all panicles were removed and weighed, panicle length was measured, and for a subsample of 178 panicles, the number of seeds was counted manually. Panicle dry weight predicted the number of seeds per panicle better (R² = 0.92) than did panicle length (R² = 0.69). The other factors except for ‘field’ and ‘seed predation’ had no effect on these relationships. The relationships between seed number and panicle dry weight found in this study closely resembled those reported in an earlier study. Based on our results, we conclude that both plant traits are appropriate for the estimatation of seed production, depending on required level of precision and availablilty of resources for the evaluation of sustainable weed management strategies.

中文翻译：

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利用穗干重估算E菜的种子产量

对杂草种子生产的更好了解是任何允许某些杂草脱落种子的长期管理的关键要素。测量杂草种子产量的挑战是时间和劳力方面的巨大努力。对于杂草species藜（Echinochloa crus-galli），测试了每穗干重或每穗长度的种子数是否可用于估计种子产量。在德国东北部的三个玉米田中进行了实验。可能影响这种关系的因素的影响，例如幼苗出苗的时间，景天肠球菌的密度包括其他杂草的防除强度，种子的捕食和田间。玉米收获前几天，将所有穗除去并称重，测量穗长度，对于178个穗的子样品，手动计算种子数。穗干重 比穗长（R ²）更好地预测了每穗的种子数（R ² = 0.92） = 0.69）。除“田间”和“种子捕食”以外的其他因素对这些关系没有影响。在这项研究中发现的种子数量和穗干重之间的关系与早期研究中报道的关系非常相似。根据我们的结果，我们得出结论，两种植物性状均适合于种子生产的估计，这取决于评估可持续杂草管理策略所需的精确度和资源可用性水平。