Department of Plant Sciences, University of California-Davis, One Shields Avenue, Davis, California 95616, USA.
Am J Bot. 2013 Oct;100(10):1991-9. doi: 10.3732/ajb.1200508. Epub 2013 Sep 26.
Cultivated tomato, Solanum lycopersicum, suffers chilling induced wilting because water movement through its roots decreases with declining soil temperatures. Certain wild tomato species exhibit resistance to chilling-induced wilting, but the extent of this chilling tolerance in wild tomatoes is not known. •
We measured shoot wilting during root chilling in wild Solanum accessions from habitats differing in elevation, temperature, and precipitation. We also measured shoot wilting during root chilling in introgression lines (ILs) with chromosome 9 segments collinear to the shoot turgor maintenance QTL stm9 region from chilling-tolerant S. habrochaites, chilling and drought-tolerant S. lycopersicoides, or drought-tolerant S. pennellii. •
Wild tomato species, which experience chilling temperatures (<10°C) in their native habitat, maintain shoot turgor under root chilling. Among accessions of S. lycopersicum var. cerasiforme, a typically chilling sensitive species, shoot turgor maintenance during root chilling was correlated with the precipitation of the native habitat. By contrast, S. pennellii, a species that is typically drought adapted, did not maintain turgor under root chilling. Grafted plants with roots containing S. habrochaites and S. lycopersicoides introgressions improved shoot turgor maintenance under root chilling. •
Resistance to chilling-induced water stress is an important adaptation to chilling temperatures in wild tomatoes. There is some overlap in adaptation to drought and chilling stress in some tomato species. Root-based resistance to chilling-induced water stress in wild tomatoes may involve orthologous gene(s).
栽培番茄（Solanum lycopersicum）由于土壤温度下降导致根部水分移动减少，易受冷胁迫萎蔫。某些野生番茄物种表现出对冷胁迫萎蔫的抗性，但野生番茄的耐寒程度尚不清楚。
我们测量了来自海拔、温度和降水不同生境的野生茄属植物在根部受冷时的植株萎蔫程度。我们还测量了来自耐寒的 S. habrochaites、耐寒耐旱的 S. lycopersicoides 或耐旱的 S. pennellii 的具有与茎膨压维持 QTL stm9 区域同源的第 9 号染色体片段的导入系（ILs）在根部受冷时的植株萎蔫程度。
在其原生境中经历低温（<10°C）的野生番茄物种在根部受冷时仍能维持茎膨压。在典型的冷敏感物种 S. lycopersicum var. cerasiforme 的品种中，根部受冷时维持茎膨压与原生境的降水有关。相比之下，典型耐旱的 S. pennellii 在根部受冷时不能维持膨压。含有 S. habrochaites 和 S. lycopersicoides 导入片段的接枝植物改善了根部受冷时的茎膨压维持。
对冷胁迫引起的水分胁迫的抗性是野生番茄适应低温的一个重要适应特征。在某些番茄物种中，对干旱和冷胁迫的适应有一定的重叠。野生番茄根部对冷胁迫引起的水分胁迫的抗性可能涉及同源基因。
