权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Studies on vsualization of freezing behaviors in plants using NMR microscopy and Infra-red thermography and mechanisms of avoiding freeze injuries.

使用核磁共振显微镜和红外热成像技术对植物冻结行为进行可视化研究以及避免冻害的机制。

基本信息

批准号：
16380030
负责人：
ISHIKAWA Masaya
金额：
$ 10.32万
依托单位：
National Institute of Agrobiological Sciences
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2007
项目状态：
已结题

项目摘要

Behavior of water(freeze or supercool)is crucial for plant tissues to survive subfreezing temperatures as their major component is water. Plants have complex tissues and observation of their freezing behaviors is not necessarily easy with conventional methods. We have developed two novel non-invasive methods to visualize freezing behaviors in plant tissues. These methods proved to be powerful tools to analyze freezing behaviors in plants, which may allow us to reveal mechanisms of cold hardiness, freezing injuries and frost injuries.1. We have established a method to visualize freezing behaviors in complex plant tissues using proton NMR(MIR)microscopy. This depends on a simple mechanism, T_2(spin-spin relaxation time)becomes extremely short when water freezes, which results in a catastrophic decrease in the contrast of NMR images.2. We successfully visualized freezing behaviors in flower buds of several woody species(Malus, Pyrus, Prunus, Cornus, Daphne). This allowed us to find novel … More types of freezing behavior in some of these flower buds and to clearly locate boundary between non-frozen and frozen tissues. Using atest tube method, we detected high ice nucleation activity in the tissue that freezes early.3. Fine freezing behaviors of various leaf tissues of Trachycarpus fortuneii(a cold hardy palm)were revealed using NMR microscopy. Mesophyll cells remained supercooled until-16C. Anti-nucleation activity was detected in the methanol extract from this palm.4. Fine freezing behaviors of various leaf tissues in a cold hardy bamboo species(Sasa kurilensis) were revealed using cryomicroscopy.5. Attempts to visualize freezing events using infra-red thermography have been made since 15 years ago in North America. However, they used raw thermography images (sensitivity being low), the transmission of freezing can be seen in tissues with high water content. In the last few years, the apparatus has been digitized, which allows thermo-images analyzed on computers. Using subtraction images and differential images, we could precisely analyze details of freezing transmission. Less

水的行为（冻结或过冷）对植物组织在冰点以下存活至关重要，因为它们的主要成分是水。植物具有复杂的组织，用传统的方法观察它们的冷冻行为并不一定容易。我们已经开发了两种新的非侵入性方法来可视化植物组织中的冷冻行为。这些方法被证明是分析植物冰冻行为的有力工具，可以帮助我们揭示抗寒性、冻害和霜害的机制。我们建立了一种利用质子核磁共振（MIR）显微镜观察复杂植物组织冷冻行为的方法。这取决于一个简单的机制，当水冻结时，T_2（自旋-自旋弛豫时间）变得非常短，这导致核磁共振图像对比度的灾难性下降。我们成功地可视化了几种木本植物（苹果、梨、李、山茱萸、达芙妮）花蕾的冻结行为。这让我们在一些花蕾中发现了更多类型的冷冻行为，并清楚地定位了非冷冻和冷冻组织之间的界限。利用试管法，我们检测到在早期冻结的组织中有较高的冰核活性。利用核磁共振显微镜研究了寒性棕榈（Trachycarpus fortuneii）不同叶组织的精细冷冻行为。叶肉细胞保持过冷直到-16℃。测定了该棕榈甲醇提取物的抗成核活性。利用低温显微镜研究了一种耐寒竹（Sasa kurilensis）不同叶片组织的精细冷冻行为。早在15年前，北美就开始尝试使用红外热成像技术来可视化冻结事件。然而，他们使用原始热成像图像（灵敏度较低），可以在高含水量的组织中看到冷冻的传输。在过去的几年里，该设备已经数字化，这使得热图像可以在计算机上分析。利用减法图像和差分图像，可以精确分析冻结传输的细节。少