摘要： 为了给小麦高光效和高抗逆相结合的高产品种选育提供理论依据，在大田条件下，以黄淮地区3个小麦主栽品种为研究对象，探究了不同小麦品种穗部光合速率和颖壳抗氧化酶活性对一天中光辐射强度变化的响应。结果表明，在不同生育时期，百农4199、矮抗58和周麦18的穗部光合速率（Pn）以及颖壳超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和抗坏血酸过氧化物酶（APX）的活性均随着一天中光辐射强度由弱到强再到弱的变化而呈现先升后降的趋势，颖壳丙二醛（MDA）的含量随着光辐射强度变化呈现先降后升的趋势。从品种比较来看，在抽穗期、开花期、花后10 d、花后20 d的7：30、11：30、13：30和17：30，百农4199的穗部光合速率分别比矮抗58高出15.72%，27.99%，28.01%和62.46%、33.49%，15.09%，20.94%和17.97%、37.90%，21.41%，6.30%和40.11%、9.34%，10.70%，17.27%和19.32%；分别比周麦18高出12.45%，19.74%，25.36%和58.58%、14.89%，3.13%，22.52%和13.48%、40.64%，25.93%，9.70%和10.89%、13.13%，21.47%，28.34%和22.53%。究其原因，百农4199的颖壳在不同时期不同光照条件下其SOD、CAT和APX等抗氧化酶活性高于矮抗58和周麦18，较高的抗氧化酶活性降低了百农4199颖壳的MDA含量，使穗部能充分利用少量的弱光或耗散多余的光能，从而使自己适应不同的光照辐射水平。

关键词: 小麦穗部, 光合速率, 颖壳, 抗氧化酶活性, 光照辐射强度

Abstract: In order to provide a theoretical support for the selection and breeding of high-yielding wheat varieties with high light efficiency and high stress resistance in the Huang-huai region, a field experiment with three wheat varieties was carried out to investigate the responses of photosynthetic rate of spike and antioxidant enzyme activity of glume to the change of light radiation intensity in one day. The results showed that the photosynthetic rate (Pn) of spikes and the activities of superoxide dismutase(SOD), catalase(CAT) and ascorbate peroxidase(APX) of glumes of Bainong 4199 (BN 4199), Aikang 58 and Zhoumai 18 all changed with the change of light radiation intensity from weak to strong to weak during the day at different growth stages.They showed a trend of rising first and then falling. And the content of malondialdehyde(MDA) showed a trend of falling first and then rising with the change of light radiation intensity. From the comparison of varieties, the spikes photosynthetic rates of BN 4199 were 15.72%, 27.99%,28.01% and 62.46%; 33.49%, 15.09%,20.94% and 17.97%; 37.90%, 21.41%,6.30% and 40.11%; 9.34%, 10.70%,17.27% and 19.32% higher than those of Aikang 58, and were 12.45%, 19.74%,25.36% and 58.58%;14.89%, 3.13%,22.52% and 13.48%; 40.64%, 25.93%,9.70% and 10.89%; 13.13%, 21.47%,28.34% and 22.53% higher than those of Zhoumai 18 at 7:30, 11:30,13:30 and 17:30 of heading stage, flowering stage, 10 days after flowering and 20 days after flowering. The reason is that the glumes of BN 4199 have higher antioxidant enzyme activities such as SOD, CAT and APX under different light conditions than Aikang 58 and Zhoumai 18. Higher antioxidant enzyme activity reduces the MDA content of BN 4199 glumes, and enables the ear to make full use of a small amount of weak light or dissipate excess light energy, thereby adapting itself to different levels of light radiation.

Key words: Wheat spike, Photosynthetic rate, Glume, Antioxidant enzyme activity, Light radiation intensity

中图分类号: 

• S512.01