不同短季棉品种衰老过程生化机理的研究

Researches on the Biochemical Mechanism of Aging Process of Different Short Season Cotton Varieties

本文对中棉所16等5个短季棉品种大田栽培条件下的第10叶片和盆栽子叶附体或离体状态下某些生化变化作了研究.结果表明,中棉所16及姊妹系中427的叶绿素和可溶性蛋白质降解慢、幅度小.超氧物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性强.中棉所10的叶绿素和可溶性蛋白质降解快、幅度大.SOD、POD、CAT活性小.辽棉7叶绿素降解速度居中,田间附体叶片蛋白质降解较慢,离体子叶则降解快,SOD、POD、CAT活性居中,在离体子叶后期高于其他品种,可能与晚熟有关,中无268叶绿素和子叶可溶性蛋白质降解慢,SOD、POD、CAT活性有特异之处,如SOD、POD活性明显高于其他品种,CAT则低于其他品种,可能与该品种无棉酚、兼抗枯黄萎病和棉蚜、棉铃虫有关.

Researches were conducted on the biochemical change in the 10th leaf of 5 short season cot-ton varieties including Zhongmiansuo 16 grown in field and in the explant cotelydon or cotelydon intact of same varieties in pots. Results show that the chlorophyll and soluble protein in the leaves of Zhongmiansuo 16 and its sibbling line Zhong 427 degrade slowly within a short range, while they show high activity of SOD, POD and CAT. The chlorophyll and soluble protein in leaves of Zhongmiansuo 10 degrade fast in great range, while its SOD, POD and CAT activity is low. The chlorophyll in leaves of Liaomian 7 degrades in an intennediate extent. Protein in the intact leaves of plants in field degrades slowly, while that in the explant leaves degrades fast. The SOD, POD and CAT show intennediate activity, but in late season their activity in explant cotelydon is higher than those in other varieties. Its late maturity may be related to this biochemical change. The chlorophyll in leaves and soluble protein in cotelydon of Zhong 268 degrads slowly. Its SOD, POD and CAT have specific activity. For example, its SOD and POD activity is significantly higher than those of other varieties, while its CAT activity is lower. This may result from no gossypol of this variety, and from its resistance to Fusarium and Vericillium wilt and to cotton aphids and bollworms.