Influence of nitrate-ammonium ratio on growth and nutrition of Arabidopsis thaliana
Influence of nitrate-ammonium ratio on growth and nutrition of Arabidopsis thaliana
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DOI：
10.1007/s11104-010-0445-8
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发表时间：
2010-11-01
期刊：
影响因子：
4.9
通讯作者：
Ouerghi, Zeineb
中科院分区：
文献类型：
--
作者：
Helali, Sabah M'rah;Nebli, Heifa;Ouerghi, Zeineb
在不同NO (3) (-) /NH(4)（+）比例的培养基中，在控制条件下水培拟南芥幼苗。培养基没有缓冲，以防止pH变化，但每2天将其pH重置为pH 5.5。当氨态氮源占主导地位时，整个植物生物量沉积减少，与此同时，揭示叶片生理状态退化的几个参数也随之减少，如叶绿素含量降低、K+、Ca2+和水分含量降低、叶片扩张受限以及细胞应激症状的出现。然而，叶片的生物量生产功能似乎没有受到影响，因为单位叶表面积的生物量生产速率保持不变。实际上，生物量减少的主要因素是叶片的消除和/或叶片起始的抑制。本文结合NH(4)（+）对拟南芥根系离子通量和K+转运系统特性影响的文献资料进行了讨论。nh4（+）对矿物质（阳离子）营养的干扰可能是氨营养有害效应的主要原因。
Arabidopsis thaliana seedlings were grown in hydroponic culture under controlled conditions in mediums with different NO (3) (-) /NH (4) (+) ratios. The mediums were not buffered, against pH change, but their pH was reset at pH 5.5 each 2 days. When ammoniacal N source was predominant, the whole plant biomass deposition was diminished, parallely to several parameters which revealed degraded leaf physiological status, such as leaf chlorosis associated with diminished chlorophyll content, lowered K+, Ca2+, and water content, along with restricted leaf expansion, and apparition of cellular stress symptoms. However, leaf functioning for biomass production did not seem affected, since biomass production rate per unit leaf surface area remained unchanged. Indeed, the main factor of decrease biomass production was leaf elimination and/or repression of leaf initiation. The results are discussed in the context of literature data on the effects of NH (4) (+) on ion fluxes at the root level and properties of K+ transport systems in Arabidopsis. Disturbance of mineral (cationic) nutrition by NH (4) (+) seemed to be a major cause of the detrimental effect of ammoniacal nutrition.