Relationship between low-temperature tolerance and vernalization response in wheat and rye
Relationship between low-temperature tolerance and vernalization response in wheat and rye
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DOI：
10.4141/cjps96-007
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发表时间：
1996-01-01
影响因子：
1.2
通讯作者：
Ward, RW
中科院分区：
文献类型：
--
作者：
Fowler, DB;Limin, AE;Ward, RW
春化反应和低温驯化是谷物为应对低温胁迫而进化而来的生存机制。这两种反应都有相似的最适诱导温度范围，并且它们受到相互关联的遗传系统的控制。也有人认为，春化的完成是冬季谷物在低温驯化的最佳温度范围内长时间保持的低温耐性逐渐丧失的原因。本研究进行了两个试验，旨在阐明小麦(Triticum aestivum L.)维管化反应与耐冷性的关系。和黑麦(Secale graale L.)所有品种的植株在恒定的4℃下开始快速的低温驯化。低温耐性的变化速度逐渐减慢，最终开始下降，形成耐低温能力与驯化阶段之间的曲线关系。维管束达到饱和的时间与保持在4℃的品种的耐冷性开始下降之间存在密切的关系。然而，在春化饱和后暴露于温暖的温度下，谷类植物至少保留了部分低温适应能力，表明维管束饱和并不会导致耐低温基因的‘’关闭‘’。不能排除春化基因在耐低温基因表达中具有更微妙的调控作用的可能性，并对未来的研究途径进行了讨论。
Vernalization response and low-temperature acclimation are survival mechanisms that cereals have evolved to cope with low-temperature stress. Both responses have similar optimum temperature ranges for induction, and they are controlled by genetic systems that are interrelated. It has also been suggested that the completion of vernalization is responsible for the gradual loss in low-temperature tolerance observed in winter cereals maintained for long periods of time at temperatures in the optimum range for low-temperature acclimation. In the present study, two experiments were conducted with the objective of clarifying the relationship between vemalization response and low-temperature tolerance in wheat (Triticum aestivum L.) and rye (Secale cereale L.). The plants of all cultivars began to low-temperature acclimate at a rapid rate when exposed to a constant 4 degrees C. The rate of change in low-temperature tolerance then gradually slowed and eventually started to decline, producing a curvilinear relationship between low-temperature tolerance and stage of acclimation. A close relationship was observed between the time to vemalization saturation and the start of the decline in low-temperature tolerance of cultivars held at 4 degrees C. However, cereal plants retained at least a partial ability to low-temperature acclimate following exposure to warm temperatures after vernalization saturation, indicating that vemalization saturation does not result in a ''switching off' of the low-temperature tolerance genes. The possibility that vernalization genes have a more subtle regulatory role in the expression of low-temperature tolerance genes could not be ruled out, and future avenues for investigation are discussed.