Seed mortality in the soil is related to seed coat thickness
Seed mortality in the soil is related to seed coat thickness
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DOI：
10.1017/s0960258510000255
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发表时间：
2010-12-01
影响因子：
2.1
通讯作者：
Colbach, Nathalie
中科院分区：
文献类型：
--
作者：
Gardarin, Antoine;Duerr, Carolyne;Colbach, Nathalie
量化种植制度对杂草动态影响的模型是测试创新种植制度的有用工具。在这些模型中，土壤中的种子死亡率是一个关键参数，以解释种植制度随着时间的推移，通过土壤种子库的累积效应。由于种子死亡率很难测量，我们的目标是开发一种方法来估计它从容易获得的信息。将13种杂草种子埋于田间30cm深处，定期回收2年，测定其生活力。种子质量，尺寸，形状，和蛋白质和脂质含量以及外壳厚度进行了测量。为了估计未包括在研究中的物种的种子死亡率，我们寻找死亡率和种子性状之间的关系。种子活力主要在埋藏的第二年下降，死亡率范围为0.01至0.63种子。种子死亡率随种皮厚度的增加而降低。没有发现与其他测量的性状或与文献中的种子持久性数据相关。这些结果得到证实时，系统发育相关性与非遗传独立的对比的影响。在所研究的物种范围内，种皮的厚度在17至231毫米之间变化，可以保护种子免受土壤中的外部攻击，并减缓种子腐烂。这种特性可以通过X射线图像很容易地测量，并可用于估计更广泛物种的种子死亡率。
Models that quantify the effects of cropping systems on weed dynamics are useful tools for testing innovative cropping systems. In these models, seed mortality in the soil is a key parameter to account for the cumulated effect of cropping systems over time via the soil seed-bank. Since seed mortality is difficult to measure, our objective was to develop a method to estimate it from easily accessible information. Seeds of 13 weed species were buried 30cm deep in fields and were recovered regularly for 2 years to measure their viability. Seed mass, dimensions, shape, and protein and lipid contents as well as coat thickness were measured. To estimate seed mortality of species not included in the study, we searched for relationships between mortality rates and seed traits. Seed viability mainly decreased during the second year of burial, with mortality rates ranging from 0.01 to 0.63 seeds.seeds(-1).year 21, depending on the species. Seed mortality decreased with increasing seed coat thickness. No correlation was found with other measured traits or with seed persistence data in the literature. These results were confirmed when the effects of phylogenetic relatedness with phylogenetically independent contrasts were included. The thickness of the seed coat, which varied between 17 and 231 mm over the range of species studied, can protect the seed from external attacks in the soil and slow down seed decay. This trait can be easily measured via X-ray images and could be used to estimate the seed mortality rate for a wider range of species.