烤烟大田生长期烟叶中淀粉合成的酶活性变化

对K326、红花大金元(HD)2个烤烟品种在云南常规施肥情况下烟叶中ADPG焦磷酸化酶、淀粉合成酶、Q酶活性的变化及可溶性总糖、还原糖和淀粉含量的变化进行了研究。结果表明：K326，HD的ADPG焦磷酸化酶、淀粉合成酶活性在移栽后第40d开始升高，都在生理成熟期第90d达到高峰，以后迅速下降。2个品种的Q酶活性高峰在移栽后80d出现，但2个品种的Q酶活性变化规律不一致。K326的Q酶活性移栽后第60d开始先下降，65d以后迅速上升，移栽后80d达到高峰后又下降IHD的Q酶活性移栽后第柏d开始一直上升，移栽后第80d达到高峰后缓慢下降。2个品种可溶性总糖、还原糖含量都在移栽后第40d迅速升高，持续稳定20d以后下降，移栽后90d又迅速上升。2个品种淀粉含量都在移栽后60d上升，在生理成熟期达到最高(HD在移栽后90d，K326在移栽后110d)。

CHANGES IN ENZYME ACTIVITIES INVOLVED IN STARCH SYNTHESIS IN TOBACCO LEAF AFTER TRANSPLANTING

Two tobacco cultivars, K 326 and HD, were grown in a field experiment and fertilizers were supplied as in local conventional agronomical practice. The changes in the activities of ADPGPPase, starch synthase and Q-enzyme and in the contents of total soluble sugars, reducing sugar and starch during the growth of the plants were recorded. The activities of ADPGPPase and starch synthase started to increase on the 40~(th) day after seedling transplanting in both cultivars, reached their maximum on the 60~(th) day and dropped sharply thereafter. Q-enzyme activity reached its maximum on the 80~(th) day after transplanting in both cultivars, but each cultivar showed a different pattern in the change of the enzyme. In the cutters of K326, Q-enzyme activity first went down around the 40~(th) day after transplanting, climbed up rapidly after the 65~(th) day, reached its maximum on the 80~(th) day and fell thereafter. In the cutters of HD, Q-enzyme activity increased from the 40~(th) day after transplanting up to the 80~(th) day, followed by a gradual decline. The content of total soluble sugars and reducing sugars increased rapidly from the 20~(th) day after transplanting, remained fairly constant for about 20 days and then declined steadily until it rose again on the 90~(th) day. Starch content went up around 60 days after transplanting and reached its maximum at the physiological maturation of the cultivars, 90 and 110 days after transplanting for HD and K 326, respectively.