農業作物產量常因受到缺水、高鹽、高溫影響而降低，植物對抗環境逆境的細胞及分子研究已有廣泛的研究。LEA蛋白在種子成熟後期大量表現，通常在缺水情形下表現量會增加。從綠豆幼苗所分離的VrDHN基因為Y2K類型dehydrin，屬於第二型的LEA蛋白。本論文藉由繪製壓力-體積曲線可得到綠豆的水勢參數。膨壓是植物體中水分狀態的重要訊息。VrDHN基因的表現量在不同的處理下會隨著膨壓的減少而有明顯的改變。實驗結果顯示當膨壓在0.1 MPa時VrDHN基因的表現量會遽增。

Crop production is often reduced by drought, high salinity, and nonoptimal temperatures. The cellular and molecular responses of plants to environmental stress have been studied intensively. The genes encoding late embryogenesis abundant (LEA) proteins are consistently represented in differential screens for transcripts with increased levels during drought. The Vigna radiata VrDHN gene which is a Y2K-type dehydrin belongs to the Group 2 LEA proteins. In the study, pressure-volume curve of mungbean leaf was plotted to obtain parameters of water status. Turgor pressure is an important factor that signals the water status of plant cells. The VrDHN mRAN expression is significantly affected by turgor loss. Our results showed that turgor potential of 0.10 MPa is the threshold for the remarkably increase of VrDHN transcripts under water stress.

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