Data from: Genetic variation in adaptive traits and seed transfer zones for Pseudoroegneria spicata (bluebunch wheatgrass) in the northwestern United States

A genecological approach was used to explore genetic variation in adaptive traits in Pseudoroegneria spicata, a key restoration grass, in the intermountain western United States. Common garden experiments were established at three contrasting sites with seedlings from two maternal parents from each of 114 populations along with five commercial releases commonly used in restoration. Traits associated with size, flowering phenology and leaf width varied considerably among populations and were moderately correlated to the climates of the seed sources. P. spicata populations from warm, arid source environments were smaller with earlier phenology and had relatively narrow leaves than those from mild climates with cool summers, warm winters, low seasonal temperature differentials, high precipitation, and low aridity. Later phenology was generally associated with populations from colder climates. Releases were larger and more fecund than most of the native ecotypes, but were similar to native populations near their source of origin. Differences among native populations associated with source climates that are logical for survival, growth and reproduction indicate that genetic variation across the landscape is adaptive and should be considered during restoration. Results were used to delineate seed transfer zones and population movement guidelines to ensure adapted plant materials for restoration activities.

本研究采用基因生态学方法，针对美国西部山间区域的关键恢复用草本植物——穗状伪羊草（Pseudoroegneria spicata）的适应性性状遗传变异展开探究。
研究在3处生境差异显著的试验点建立了同质园试验（common garden experiment），供试材料涵盖114个种群各2株母本来源的幼苗，以及5种常用于植被恢复的商用推广品种。
种群间在株型、开花物候及叶宽等性状上存在显著分化，且这些性状与种源地气候呈中等程度相关。相较于夏季凉爽、冬季温暖、季节温差小、降水量充沛且干旱度较低的温和气候种源，源自温暖干旱生境的穗状伪羊草种群株型更矮小、物候更早且叶宽相对较窄；物候延迟的种群则多源自气候更为寒冷的区域。
商用推广品种的株型及繁殖力均优于多数本土生态型，但与其种源地附近的本土种群性状高度相似。本土种群间的性状差异与其种源地气候高度适配，且该差异对物种存活、生长及繁殖均具有适应性意义，这表明区域尺度上的遗传变异具有适应性，在植被恢复工作中应予以充分考量。
本研究结果可用于划定种子调拨区（seed transfer zones）及种群迁移指导准则，以保障植被恢复活动所用植物材料的适应性。