摘要
以玉米杂交种 3119为试材 ,研究了两种光照 ( 4 0 0 μ mol· m-2· s-1和 2 0 0 μ mol· m-2· s-1)和 5种供氮水平 ( 0、 7.5、 15、 2 2 .5和 30 m mol NO-13 / L)对玉米光合和碳、氮代谢的影响。强光下植株具有较高的呼吸速率、较大的光合潜力和光合速率 ,物质生产能力较高 ,光合产物更多地分配到根系之中。同时强光下植株的硝酸还原酶活性、谷氨酸脱氢酶活性以及可溶性蛋白质的含量较高 ,叶片中的硝酸盐含量较低 ,具有较高的氮素同化能力。两种光强下植株的物质生产和氮素同化能力均随供氮水平的增加先升后降 ,弱光下植株在较低的供氮水平下具有较高的物质生产能力和氮素同化能力 ,而强光下植株的最大光合物质生产能力和氮素同化能力出现在较高的氮素水平。在 N2～ N5处理 ,强光下植株的根冠比均高于弱光下的植株 ,且二者的差异随供氮量的增加而增加 ,但在缺氮处理 ( N1处理 ) ,弱光下的根冠比反而高于强光下的植株。强光下植株与弱光下的植株相比具有较高的可溶性糖和淀粉含量 ,两种光强下可溶性糖的差异随供氮量的增加呈现减少的趋势 ,而淀粉含量的差异在 N2水平为最小值 ,高于或低于 N2水平均使二者的差异扩大。在低氮条件下植株的可溶性糖和淀粉的含量较高 ,蛋白质含量较低 。
The interaction of growth light condition and nitrogen supply on maize ( Zea ma ys L.) development and photosynthetic characteristic was studied in 1997～1999 . The seedling of maize hybrids 3119 was cultivated with sands under two kinds o f light condition (400 μmol·m -2 ·s -1 and 200 μmol·m -2 ·s -1 ) and five kinds of nitrogen supply (the contents of NO -1 3 in Hoag land cultivation solution was 0, 7.5, 15, 22.5 and 30 mmol/L respectively. The p lants grown under high light density had higher respiration rate, higher photosy nthetic productivity and dry matter capacity, and more photosynthetic production was distributed into the root system compared with those under low light densit y. Also a higher activity of nitrate reductase and glutamate dehydrogenase, a hi gher contents of soluble protein, a less contents of nitrate in leaf and a highe r nitrogen assimilation were presented in plants under high light density. The d ry matter productivity and the ability of nitrogen assimilation increased first and then decreased as the nitrogen supply increased, and the turning point under high light density was presented at higher level of nitrogen supply compared wi th those under low light density. The level of nitrogen supply in which plants h ad highest dry matter capacity and nitrogen assimilation rate was higher under h igh light density than that under low light density. From N2 to N5 treatment, pl ants grown under high light density had a higher value of root/shoot than those grown under low light density, and the difference between high and low light den sity raised as the nitrogen supply increased. But under the nitrogen deficit str ess plants under low light density had higher ratio of root/shoot. Plants grown u nder high light density had higher contents of soluble sugar and starch, the dif ference of sugar between two light condition decreased as the nitrogen supply in creased. More soluble sugar and starch and less soluble protein were found in pl ants under low nitrogen supply, and it was inverse in those under high nitrogen supply. It is concluded that the suitable nitrogen supply under low light densit y is less than that under high light density.
出处
《作物学报》
CAS
CSCD
北大核心
2000年第6期806-812,共7页
Acta Agronomica Sinica
基金
国家九五科技攻关重中之重资助项目
关键词
光
氮素
玉米
光合特性
氮代谢
氮代谢
Maize
Light
Light Density
Nitrogen
Carbon metabolism
Nitrogen metabolism
Photosynthetic trait
