抗寒种衣剂对早籼稻秧苗抗寒性的影响及其作用机理的研究

【目的】探明抗寒种衣剂对水稻秧苗抗寒性的影响及其作用机理。【方法】研究了两个早籼稻品种经4种抗寒种衣剂（HET种衣剂、YKJ种衣剂、YKZYJ种衣剂和ABA种衣剂）包衣处理后在低温胁迫下的若干生理生化效应。【结果】在低温胁迫下，抗寒种衣剂处理使秧苗根系活力、过氧化物酶（POD）、过氧化氢酶（CAT）、超氧化物歧化酶（SOD）活性和叶绿素含量维持较高水平，丙二醛（MDA）含量和电解质外渗率降低，可溶性糖和游离脯氨酸大量积累，受害株率大幅下降。【结论】抗寒种衣剂增强了秧苗抵抗低温胁迫的能力；4种抗寒种衣剂的抗寒效果以YKZYJ种衣剂最优，YKJ和ABA种衣剂次之，HET种衣剂再次。

Effect and Mechanism of Cold Tolerant Seed-Coating Agents on The Cold Tolerance of Early Indica Rice Seedlings

Abstract: Physiological and biochemical effects of 4 cold resistant seed-coating agents(HET、YKJ、YKZYJ and ABA seed coating agent )on two early rice varieties were studied under chilling stress．The result showed that，under chilling stress，cold resistant seed coating agents maintained a rather high level of root vigour, POD, CAT and SOD activities and chlorophyll content, retarded the decline of soluble protein, reduced MDA content and electrolyte leakage, accumulated a great deal of soluble sugar and free proline, and decreased plant damage rate by a big margin, indicating that the cold resistant seed coating agents improved the ability of rice seedlings in resisting to chilling stress. Efficiency of cold resistance of YKZYJ was the best among the four cold resistant seed-coating agents tested. Key words： Rice; Cold resistant seed-coating agent; Chilling stress; Physiology and biochemistry, Mechanism of cold resistance