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北方針葉樹トドマツの低温への適応 ： 耐凍性獲得のタイミングと遺伝的変異
石塚, 航;小野, 清美;原, 登志彦;後藤, 晋
Permalink : http://hdl.handle.net/2115/59077
JaLCDOI : 10.14943/lowtemsci.73.81
Abstract
冬期の気候が寒冷な北方林に生育する常緑樹木は, その厳しい環境を耐え抜くために十分な耐凍性を有する必要があり, 耐凍性獲得と呼ばれる季節的な応答を示す. この耐凍性獲得タイミングには凍害回避と成長の間のフェノロジカル・トレードオフが存在すると考えられ, 植物の応答タイミングは生育する環境の中で受容する環境シグナルをもとに適切に調節されていると推察される. モデルアプローチによって, 気温変動を利用したシグナルで耐凍性獲得の調節機構と, そこに内在する遺伝的変異とを定量的に評価することができるようになってきた.
In boreal forests with cold winters, evergreen coniferous species must develop adequate freezing tolerance to survive in the severe climate. Such species show autumn cold hardening as a seasonal acclimation response. It is important that the cold hardening occurs at a suitable time in each local climate,but there is a phenological trade-off between later hardening,which lengthens the active growth period,and earlier hardening,which avoids frost damage. Various kinds of environmental signals that vary locally might regulate hardening in plants. A modeling approach can extend our knowledge of the relationship between temperature- related signals and plants’ ontogenetic development of autumn cold hardiness, thereby enabling us to quantify intraspecific variations in freezing tolerance.
In boreal forests with cold winters, evergreen coniferous species must develop adequate freezing tolerance to survive in the severe climate. Such species show autumn cold hardening as a seasonal acclimation response. It is important that the cold hardening occurs at a suitable time in each local climate,but there is a phenological trade-off between later hardening,which lengthens the active growth period,and earlier hardening,which avoids frost damage. Various kinds of environmental signals that vary locally might regulate hardening in plants. A modeling approach can extend our knowledge of the relationship between temperature- related signals and plants’ ontogenetic development of autumn cold hardiness, thereby enabling us to quantify intraspecific variations in freezing tolerance.
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