Genetic and physiological basis of adaptive salt tolerance divergence between coastal and inland Mimulus guttatus
Genetic and physiological basis of adaptive salt tolerance divergence between coastal and inland Mimulus guttatus
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DOI：
10.1111/j.1469-8137.2009.02901.x
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发表时间：
2009-01-01
期刊：
影响因子：
9.4
通讯作者：
Willis, John H.
中科院分区：
文献类型：
--
作者：
Lowry, David B.;Hall, Megan C.;Willis, John H.
局部适应是一种公认的现象，栖息地介导的自然选择推动了种群的分化。然而，关于特定性状和基因座如何结合导致局部适应的研究很少。在这里，我们进行了一系列实验，以确定哪些生理机制有助于沿海多年生和内陆一年生生态型之间的局部适应差异。利用数量性状基因座(QTL)定位与耐盐性和叶片钠离子浓度相关的基因座。为了确定这些QTL是否赋予田间适合性，我们用重组自交系(RIL)进行了相互移植试验，检验了它们的效应。沿海植物具有更高的叶片Na+浓度和更高的组织耐受性，但在渗透胁迫耐受性方面没有差异。3个QTL与耐盐雾有关，2个QTL与叶片Na+浓度有关。3个耐盐雾QTL在沿海田间均有显著的适合度效应，而在内陆没有显著的适合度效应。叶片Na+QTL在田间没有可检测到的适合度效应，其生理结果与沿海种群对盐雾和土壤盐分的适应一致。新植物学家(2009年)183：776-788doi：10.1111/j.1469-8137.2009.02901.x。
P>Local adaptation is a well-established phenomenon whereby habitat-mediated natural selection drives the differentiation of populations. However, little is known about how specific traits and loci combine to cause local adaptation.Here, we conducted a set of experiments to determine which physiological mechanisms contribute to locally adaptive divergence in salt tolerance between coastal perennial and inland annual ecotypes of Mimulus guttatus. Quantitative trait locus (QTL) mapping was used to discover loci involved in salt spray tolerance and leaf sodium (Na+) concentration. To determine whether these QTLs confer fitness in the field, we examined their effects in reciprocal transplant experiments using recombinant inbred lines (RILs).Coastal plants had constitutively higher leaf Na+ concentrations and greater levels of tissue tolerance, but no difference in osmotic stress tolerance. Three QTLs contributed to salt spray tolerance and two QTLs to leaf Na+ concentration. All three salt-spray tolerance QTLs had a significant fitness effects at the coastal field site but no effects inland. Leaf Na+ QTLs had no detectable fitness effects in the field.Physiological results are consistent with adaptation of coastal populations to salt spray and soil salinity. Field results suggest that there may not be trade-offs across habitats for alleles involved in local salt spray adaptations.New Phytologist (2009) 183: 776-788doi: 10.1111/j.1469-8137.2009.02901.x.