Phenotypic plasticity and bet-hedging in a heterocarpic winter annual/spring ephemeral cold desert species of Brassicaceae
Phenotypic plasticity and bet-hedging in a heterocarpic winter annual/spring ephemeral cold desert species of Brassicaceae
复制标题
十字花科异果性冬季一年生/春季短暂冷漠物种的表型可塑性和下注对冲
DOI：
10.1111/j.1600-0706.2011.19800.x
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发表时间：
2012-03-01
期刊：
影响因子：
3.4
通讯作者：
Baskin, Carol C.
中科院分区：
文献类型：
--
作者：
Lu, Juan J.;Tan, Dun Y.;Baskin, Carol C.
表型可塑性对植物在环境波动生境中的定殖和存活起着重要作用。这项研究的主要目的是确定非生物水平的影响，（土壤水分和养分供应）和生物（密度和植食性）因素对异形裂上部的数量和比例质量分配的表型可塑性的影响（高分散，低休眠）和不裂的低（低分散，高休眠）来自不同种子形态的寒冷沙漠冬季一年生/春季短命Diptychocarpus strictus的个体的长角果。在一个试验园中播种的种子产生的植物受到不同水平的土壤水分，养分供应，密度和模拟植食动物。测量分配给营养和生殖成分的质量，并计算上部和下部角果的数量。除营养条件下上、下角果数比差异不显著外，各处理间的单株质量、生殖质量、上、下角果数、各角果形态的数量和质量、单株种子质量、上、下角果数比和个体各器官的质量分配差异显著。在有利环境下，上/下角果率相对较高，而在不利环境下，上/下角果率相对较低。上部和下部角果的相对分配呈显著负相关，表明在良好的生长条件下分配到上部角果是以牺牲分配到下部角果为代价的。这似乎是第一次报告的影响，食草动物的一水硬铝石形态比在异果植物和一个只有极少数的影响，密度对形态比在这组。In D.严格地说，压力与非压力的增长条件引起的异形散生体，这本身被认为是赌注对冲的比例的转变。
Phenotypic plasticity can play an important role in colonization and survival of plants in an environmentally fluctuating habitat. The primary aim of this study was to determine the influence of level of abiotic (soil moisture and nutrient availability) and biotic (density and herbivory) factors on phenotypic plasticity in the number and proportional mass allocation to the heteromorphic dehiscent upper (high dispersal, low dormancy) and indehiscent lower (low dispersal, high dormancy) siliques of individuals of the cold desert winter annual/spring ephemeral Diptychocarpus strictus derived from different seed morphs. Plants produced from seeds sown in an experimental garden were subjected to different levels of soil moisture, nutrient supply, density and simulated herbivory. Mass allocated to vegetative and reproductive components was measured and number of upper and lower siliques counted. Except for number ratio of upper: lower siliques under nutrient supply, levels of the four treatments resulted in significant variation in total plant mass, reproductive mass, number of siliques (upper and lower), number and mass of each silique morph, individual seed mass, upper/lower silique ratio and mass allocation to each organ in an individual. In favorable environments, the upper/lower silique ratio was relatively high, while in unfavorable environments it was relatively low. The relative allocation to upper and lower siliques was significantly negatively correlated, suggesting that allocation to upper siliques in good growth conditions occurred at the expense of allocation to lower siliques. This appears to be the first report on the effect of herbivory on diaspore morph ratio in heterocarpic plants and one of only a very few on the effect of density on morph ratio in this group. In D. strictus, stressful vs nonstressful growth conditions caused a shift in the ratio of heteromorphic diaspores, which themselves are assumed to be bet-hedging.