Ongoing domestication of whole-leaf rosinweed, Silphium integrifolium Michx., as a perennial oilseed and forage crop aims to increase yields while limiting decreases in other desirable traits (i.e., trade-offs). Two changes to plant architecture, increasing pistillate ray florets head⁻¹ ( = feminization) and reduced lateral branching of stems, have been considered for their potential to improve oil yields but with limited understanding of potential trade-offs. Field tests with genets that vary for feminization failed to show that increasing the number of female florets head⁻¹ had any effect on pollinator visitation and seed set (%) but revealed that feminization reduced embryo mass achene⁻¹. In general, tripling the number of ray florets head⁻¹ reduced the mass of individual embryos by 50% or more, which suggests feminization still provides a net benefit for oil yields. Clipping (bud removal) used to simulate reduced branching in S. integrifolium affected components of yield in ways that were generally predictable; heads (receptacles) became larger and mass achene⁻¹ increased. However, the large number of buds removed to achieve modest increases in head size and achene mass make reduced branching appear undesirable. Ultimately, S. integrifolium genets with genetically reduced branching are needed to make the best evaluation of this potential change. Both sets of experiments reveal plasticity in S. integrifolium yield components and suggest that efforts to improve the quality of phenotypic data are important to efficient selection.

中文翻译：

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Silphium integrifolium Michx 结构的变化。在驯化过程中揭示了产量的新权衡

全叶松香（Silphium integrifolium Michx.）作为多年生油料和饲料作物的持续驯化旨在提高产量，同时限制其他理想性状的下降（即权衡）。植物结构的两个变化，增加雌性射线小花头^-1（=女性化）和减少茎的侧枝，已被认为具有提高油产量的潜力，但对潜在权衡的理解有限。对不同基因的雌性化进行的田间试验未能表明增加雌性小花头^-1的数量对传粉者的访问和种子组 (%) 有任何影响，但表明雌性化减少了胚胎质量瘦果^-1. 一般而言，将头状小花头^-1的数量增加三倍可使单个胚胎的质量减少 50% 或更多，这表明女性化仍然为油产量提供了净收益。剪裁（去除芽）用于模拟整合链球菌中减少的分枝，以通常可预测的方式影响产量的组成部分；头（贮器）变大，瘦果质量^-1增加。然而，为了实现头部大小和瘦果质量的适度增加而去除大量芽，使得减少的分枝看起来不受欢迎。最终，需要具有遗传减少的分支的整合叶链球菌基因来对这种潜在变化进行最佳评估。两组实验都揭示了可塑性S. integrifolium产量成分，并表明努力提高表型数据的质量对于有效选择很重要。