2005 Fiscal Year Final Research Report Summary
Study on the responses of wintering plants to stresses caused by acid snow
| Project/Area Number |
16580270
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Boundary agriculture
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| Research Institution | Hokkaido University |
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Principal Investigator |
ARAKAWA Keita Hokkaido Univ., Grad.Sch.Agriculture, Associate Prof., 大学院・農学研究科, 助教授 (00241381)
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| Project Period (FY) |
2004 – 2005
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| Keywords | Air pollution / Environmental stress / Acid snow / Wintering plants / Sulfuric acid / Extracellular freezing / Injury / Winter wheat |
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| Research Abstract |
Acid precipitation (acid rain or acid mist) is an environmental problem that has affected ecosystems and agriculture. Acid snow might be also an environmental stress factor for wintering plants since acid precipitates are locally concentrated in snow and the period in which ice crystals are in contact with shoots might be longer than that of acid precipitates in rain. In this study, 'equilibrium' and 'prolonged', freezing tests with sulfuric acid, which simulate situations of temperature depression and chronic freezing at a subzero temperature with acid precipitate as acid snow stress, respectively, were carried out using leaf segments of cold-acclimated winter wheat (Triticum aestivum L.). When leaf segments were frozen in the presence of sulfuric acid solution (pH 4.0,3.0 or 2.0) by equilibrium freezing with ice-seeding, the survival rate of leaf samples treated with sulfuric acid (pH 2.0) decreased markedly. Leaf samples after supercooling to -4 and -8℃ in the presence of sulfuric acid solution (pH 2.0) without ice-seeding were less damaged. When leaf samples were subjected to prolonged freezing at -4 and -8℃ for 7 days with sulfuric acid (pH 2.0), the survival rates of leaf samples exposed to sulfuric acid decreased more than those of leaf samples treated with water. On the other hand, leaf samples were less damaged by prolonged supercooling at -4 and -8℃ for 7 days with sulfuric acid (pH 2.0). The results suggest that an acid condition in the process of extracellular freezing and/or thawing promotes freezing injury of wheat leaves, because of the combined effects of acid substances concentrated in snow crystals and freeze-thaws in an acid solution concentrated by freezing. For further characterization of the responses of wintering plants to acid-snow stress, studies on the mechanism of injury caused by acid-snow stress are in progres.
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Research Products
(29 results)
