小麦抗寒性

Wheat cold hardiness can affect blossom time

小麦的抗寒性可影响到开花时间

New research by UC Davis wheat geneticist（遗传学者）Jorge Dubcovsky and his colleagues could lead to new strategies for improving freezing tolerance in wheat, which provides more than one-fifth of the calories consumed by people around the world. The new findings, published June 22 in the Online First issue of the journal Plant Physiology, shed light on（阐明）the connection between flowering and freezing tolerance in wheat.

In winter wheat and barley（大麦）varieties, long exposures to non-freezing cold temperatures accelerate flowering time in a process known as vernalization（春化处理，种子催熟法） . These exposures also prepare the wheat to better tolerate freezing, a process known as cold acclimation（适应环境） .

In their new study, Dubcovsky and his colleagues at UC Davis, The Ohio State University and in Hungary, demonstrated that when the main vernalization gene, VRN1, is expressed in the leaves, it initiates a process that leads to decreased expression of the freezing tolerance genes. (In genetics, "expression" refers to the process by which information carried by the gene is used to create a protein.)

"This system enables wheat and other temperate grasses to respond differently to cool temperatures in the fall than they would to cool temperatures in the spring," said Dubcovsky, a professor in UC Davis' Department of Plant Sciences.

Dubcovsky heads UC Davis' wheat breeding program and Wheat Molecular Genetics Laboratory. The lab coordinates a broad-based research program that aims to provide the scientific information needed to develop healthier and more productive varieties of wheat.

He noted that a cool temperature in the fall, when plants have low levels of the vernalization gene VRN1, activates the freezing tolerance genes, helping to trigger the plants' acclimation to cold temperatures. This is essential in the fall, when cool temperatures are an indication that winter's freezing temperatures are approaching.

"However the same cool temperature in the spring, when high levels of the vernalization gene VRN1 are present in the leaves, results in a weaker response of the freezing tolerance genes," Dubcovsky said. "This avoids initiating the plants' cold-acclimation response, which requires a lot of the plants' energy and is unnecessary in the spring because warmer weather is approaching."

新的研究的加州大学戴维斯分校小麦遗传学家（遗传学者）豪尔赫dubcovsky和他的同事可能导致新的战略，提高小麦抗冻性，它提供了超过五分之一的热量消耗的世界各地的人们。新的研究结果，发表在六月二十二日第一期在线植物生理学杂志，揭示（阐明）之间的联系，开花和小麦抗冻性。

冬小麦大麦（大麦）品种，长期暴露在非冻结性冷的温度加快开花时间在一个过程称为春化作用（春化处理，种子催熟法）。这些风险也准备小麦更好地容忍冻结，这一过程称为冷驯化（适应环境）。

在他们的新研究，dubcovsky和他的同事在戴维斯大学，俄亥俄州立大学，在匈牙利，表明，当主春化基因VRN 1，表示，在叶片中，它将启动一个进程，导致减少表达的抗冻基因。（遗传学，“表达”是指的过程，信息进行的基因是用来创建一个蛋白质。）

“这个系统使小麦和其他温带牧草在不同的反应温度下冷却的冷却温度比他们将在春天，说：“dubcovsky，教授在加州大学戴维斯植物科学系。

dubcovsky头加州大学戴维斯分校的小麦育种和小麦分子遗传学实验室。实验室坐标的一个基础广泛的研究计划，旨在提供科学信息需要发展更健康和更富有成效的小麦品种。

他指出，一个凉爽的温度在秋季，当植物有低水平的春化基因，激活抗冻基因，帮助引发植物冷驯化温度。这是必不可少的秋天，当凉爽的温度是一个迹象表明，冬季的冻结温度接近。

然而同样的凉爽温度在春季，当高水平的春化基因存在于叶片，结果在一个弱的抗冻基因，“dubcovsky 说。”这避免了启动植物冷驯化反应，这需要很多植物的能量是不必要的，在春天，温暖的天气即将来临。”