Life histories of the perennial geophyte Erythronium grandiflorum (Liliaceae) in Colorado subalpine transplant garden from annual measurements, 1991 onward

In an outdoor garden at Irwin, Colorado, we established glacier lily plants in open-bottomed PVC pots that protected them from gopher attack. The initial cohorts were excavated from field sites as mature corms of unknown age. Later cohorts were grown from seed, so their ages are known. Each spring since 1991, we have noted fruit and flower production. In August, after the aboveground parts have died back, we exhume the plants, wash off the soil, weigh the corms, characterize their morphology, photograph them, and replant them. If a corm splits, we replant the pieces in separate pots. The study is ongoing, with 264 plants in 2019. Main findings through 2020: plants produce 0-4 flowers per year, depending on size; most plants flower each year; death is rare, with many plants having survived the entire study; setting a fruit reduces corm substantially (cost of reproduction); plants appear to regulate weight by adjusting flower production, and by splitting; genotypes vary in splitting propensity. Oddly, mortality is higher in very large corms than in mid-sized ones. Evidence for senescence is scant.

我们在科罗拉多州欧文（Irwin）的户外实验园中，将冰川百合（glacier lily）植株种植于底部开口的聚氯乙烯（PVC）盆中，以避免其遭受囊鼠的侵害。初始批次的植株以未知树龄的成熟球茎形式从野外样地挖掘获得，后续批次则由种子培育而来，因此其生长年龄已知。自1991年起，我们于每年春季记录植株的开花与结实情况。每年8月，待地上部分枯萎脱落之后，我们将植株挖出，冲洗附着的土壤、称量球茎重量、观测其形态特征、拍摄照片后重新定植。若球茎发生分裂，则将分裂后的子球分别栽种于不同盆中。本研究目前仍在进行中，截至2019年共保有264株植株。截至2020年的主要研究结果如下：植株每年可开出0至4朵花，花量取决于球茎大小；多数植株每年均可开花；植株死亡率极低，多数个体可存活至整个实验周期；结实行为会显著降低球茎重量，即繁殖成本；植株似乎可通过调控开花量与球茎分裂来维持体重；不同基因型的球茎分裂倾向存在差异。值得注意的是，超大球茎的死亡率高于中等大小的球茎；目前几乎未发现植株衰老的相关证据。