不同生育期大豆叶片、叶柄及茎中游离脯氨酸对不同水分胁迫的反应

本实验分别测定了两个大豆品种在四种不同水分条件下叶片、叶柄和茎中游离脯氨酸浓度的变化。并对大豆在开花期、结英期以及鼓粒期体内脯氨酸的变化动态进行了研究。结果表明:在正常供水条件下,从开花期到鼓粒期随着生育期的进展,两个大豆品种叶片、叶柄和茎中的脯氨酸浓度均保持着增长趋势,并且脯氨酸浓度在各生育期都是按叶片、叶柄、茎而依次降低。正常供水条件下,抗旱性较强的“7605”各测定部位的脯氨酸浓度在各生育期均高于抗旱性较弱的“鲁豆四号”。“鲁豆四号”体内的脯氨酸对水分胁迫的反应要比“7605”敏感得多,而且在水分胁迫下脯氨酸累积能力明显高于“7605”。两个大豆品种体内脯氨酸对水分胁迫的反应因部位不同、生育期不同以及胁迫程度不同而不同。我们认为脯氨酸不能作为大豆抗旱性的有效指标。

The Responses of Free Proline in Leaves, Petioles, and Stems of Two Soybean Cultivars to Different Water Stress at Differet Development Stages

The variation of free proline concentrations of leaves, petioles, and stems in two soybean cultivars grown in different water conditions have been studied at different development stages. In favourable water condition an increasing tendency of free proline concentrations of leaves, stems, and petioles in two soybean cultivars was established from flowering stage to seedfilling stage, and a gradient of decreasing free proline concentration was found in this order of priorities: leaf, petiole, stem, at each development stage, the free prolin concentrations of drought resistent "7605"in each determined part were higher than those of drought susceptible "Ludou No.4", but under water stress the proline accumulating capacity of "Lu dou No.4" was obviously higer than that of "7605". The responses of free proline in two cultivars to water stress varied with determinded part, development stage, and stress degree. It is sugested that the free proline should not be utilized as an index of drought resistence in soybean.