Ultraviolet-B radiation and nitrogen affect the photosynthesis of maize:: a Mediterranean field study
Ultraviolet-B radiation and nitrogen affect the photosynthesis of maize:: a Mediterranean field study
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DOI：
10.1016/j.eja.2004.05.002
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发表时间：
2005-03-01
影响因子：
5.2
通讯作者：
Torres-Pereira, JMG
中科院分区：
文献类型：
--
作者：
Correia, CM;Pereira, JMM;Torres-Pereira, JMG
研究了UV-B辐射对玉米叶片气体交换速率、叶绿素荧光、色素、可溶性糖、淀粉、可溶性蛋白质和羧化酶活性的影响。在地中海田间条件下，研究了四种施氮水平（0、100、200和300 kg ha（-1）N）下的土壤肥力。该实验模拟了葡萄牙上空20%的平流层臭氧消耗。补充UV-B辐射和氮素缺乏降低了光合速率和蒸腾速率、气孔导度、总叶绿素、总类胡萝卜素、可溶性糖和UV-B吸收化合物浓度，以及PSII中电子受体库的大小和核酮糖-1，5-二磷酸羧化酶加氧酶（RuBisCO）和磷酸烯醇丙酮酸羧化酶（PEPCase）的活性。增强UV-B和氮缺乏增加最小和最大叶绿素荧光。UV-B辐射对玉米光合作用的影响与植株的营养状况有关，氮胁迫下玉米的净光合速率下降幅度较小。同时，高UV-B条件下，光合作用受氮素营养的影响较小。对于RuBisCO和PEPCase活性获得了类似的结果。氮饥饿的植物有较高的可溶性蛋白质在高UV-B相比，环境UV-B。在UV-B辐射条件下，氮素剥夺植株的淀粉含量高于其他处理。这些结果的潜在机制进行了讨论。(c)2004 Elsevier B. V.保留所有权利。
The effects of UV-B radiation on the gas exchange rates, chlorophyll fluorescence, pigmentation, soluble sugars, starch, soluble proteins and carboxylating enzyme activities of maize (Zea mays L.) were investigated at four levels of applied nitrogen (0, 100, 200 and 300 kg ha(-1) of N) under Mediterranean field conditions. The experiment simulated a 20% stratospheric ozone depletion over Portugal. Supplementary UV-B radiation and N deficiency reduced photosynthetic and transpiration rate, stomatal conductance, total chlorophyll, total carotenoids, soluble sugars and UV-B absorbing compounds concentration, as well as the pool size of the electron acceptors in PSII and ribulose-1,5-bisphosphate carboxylase oxygenase (RuBisCO) and phosphoenolpyruvate carboxylase (PEPCase) activities. Enhanced UV-B and N deficiency increased minimal and maximal chlorophyll fluorescence. The effect of additional UV-B on maize photosynthesis was dependent on the plant nutritional status, since the lower reduction of net photosynthetic rate occurred in N-stressed plants. At the same time, photosynthesis was less affected by N nutrition under high UV-B. Similar results were obtained for RuBisCO and PEPCase activities. N-starved plants had higher amounts of soluble proteins at high UV-B as compared to ambient UV-B. The starch concentration of N-deprived plants at ambient UV-B was higher than all other treatments. The underlying mechanisms for these results are discussed. (c) 2004 Elsevier B.V. All rights reserved.