Department of Molecular Plant Physiology, Utrecht University, 3584 CH Utrecht, The Netherlands.
Plant Physiol. 2012 Dec;160(4):2083-92. doi: 10.1104/pp.112.206649. Epub 2012 Oct 18.
Dormancy is a state of metabolic arrest that facilitates the survival of organisms during environmental conditions incompatible with their regular course of life. Many organisms have deep dormant stages to promote an extended life span (increased longevity). In contrast, plants have seed dormancy and seed longevity described as two traits. Seed dormancy is defined as a temporary failure of a viable seed to germinate in conditions that favor germination, whereas seed longevity is defined as seed viability after dry storage (storability). In plants, the association of seed longevity with seed dormancy has not been studied in detail. This is surprising given the ecological, agronomical, and economic importance of seed longevity. We studied seed longevity to reveal its genetic regulators and its association with seed dormancy in Arabidopsis (Arabidopsis thaliana). Integrated quantitative trait locus analyses for seed longevity, in six recombinant inbred line populations, revealed five loci: Germination Ability After Storage1 (GAAS1) to GAAS5. GAAS loci colocated with seed dormancy loci, Delay Of Germination (DOG), earlier identified in the same six recombinant inbred line populations. Both GAAS loci and their colocation with DOG loci were validated by near isogenic lines. A negative correlation was observed, deep seed dormancy correlating with low seed longevity and vice versa. Detailed analysis on the collocating GAAS5 and DOG1 quantitative trait loci revealed that the DOG1-Cape Verde Islands allele both reduces seed longevity and increases seed dormancy. To our knowledge, this study is the first to report a negative correlation between seed longevity and seed dormancy.
休眠是一种代谢停滞的状态,它有助于生物体在与正常生活过程不兼容的环境条件下生存。许多生物体都有深度休眠阶段,以促进延长寿命(增加长寿)。相比之下,植物具有种子休眠和种子寿命,这两个特征被描述为两个不同的特征。种子休眠被定义为在有利于发芽的条件下,有活力的种子暂时无法发芽的现象,而种子寿命则被定义为干燥储存(贮藏性)后种子的活力。在植物中,种子寿命与种子休眠之间的联系尚未得到详细研究。考虑到种子寿命在生态、农艺和经济方面的重要性,这是令人惊讶的。我们研究了种子寿命,以揭示其遗传调控因子及其与拟南芥(Arabidopsis thaliana)种子休眠的关系。对六个重组自交系群体中的种子寿命进行综合数量性状位点分析,揭示了五个位点:Germination Ability After Storage1 (GAAS1) 到 GAAS5。GAAS 位点与种子休眠位点 Delay Of Germination (DOG) 共定位,该位点之前在同一六个重组自交系群体中被鉴定出来。GAAS 位点及其与 DOG 位点的共定位通过近等基因系得到了验证。观察到了一个负相关,深度种子休眠与低种子寿命相关,反之亦然。对共定位的 GAAS5 和 DOG1 数量性状位点的详细分析表明,DOG1-Cape Verde Islands 等位基因既降低了种子寿命,又增加了种子休眠。据我们所知,这项研究首次报道了种子寿命和种子休眠之间的负相关关系。