N-fertilization has different effects on the growth, carbon and nitrogen physiology, and wood properties of slow- and fast-growing Populus species
N-fertilization has different effects on the growth, carbon and nitrogen physiology, and wood properties of slow- and fast-growing Populus species
复制标题
施氮肥对慢生和快生杨树种的生长、碳氮生理和木材特性有不同的影响
DOI：
10.1093/jxb/ers271
复制
发表时间：
2012-10-01
影响因子：
6.9
通讯作者：
Luo, Zhi-Bin
中科院分区：
文献类型：
--
作者：
Li, Hong;Li, Mengchun;Luo, Zhi-Bin
研究氮肥对生长特性不同的杨树生长、碳氮素生理和木材性质的影响。研究了不同氮素水平对杨树幼树生长的影响。地上部生物量、叶面积、光合速率(A)、瞬时光合氮利用效率(PNUEi)、叶绿素和叶糖浓度均高于PP。叶片硝酸还原酶(NR)活性和根系谷氨酸合成酶(GOGAT)活性PG高于PP，新梢N量和NUE也高于PP。PG木材的木素含量和热值均低于PP木材。氮肥对PG根系生物量的降低幅度大于PP，但对PG的叶生物量、叶面积、A和PNUEi的增加幅度大于PP。在参与氨氮、硝酸盐运输或氮素同化的13个基因中，PG的转录本表现出比PP更显著的氮肥变化。化肥对硝酸还原酶活性和氮素含量的增加幅度大于化肥处理。在这两种植物中，施氮肥导致较低的热值以及较短和较宽的导管分子/纤维。这些结果表明，速生杨树的生长、碳素、氮素生理和木材性质对氮素有效性的增加比慢生杨树更敏感，这可能是因为在高氮水平下，速生杨树优先分配资源到叶片，加速了氮素生理过程。
To investigate how N-fertilization affects the growth, carbon and nitrogen (N) physiology, and wood properties of poplars with contrasting growth characteristics, slow-growing (Populus popularis, Pp) and fast-growing (P. albaP. glandulosa, Pg) poplar saplings were exposed to different N levels. Above-ground biomass, leaf area, photosynthetic rates (A), instantaneous photosynthetic nitrogen use efficiency (PNUEi), chlorophyll and foliar sugar concentrations were higher in Pg than in Pp. Foliar nitrate reductase (NR) activities and root glutamate synthase (GOGAT) activities were higher in Pg than in Pp as were the N amount and NUE of new shoots. Lignin contents and calorific values of Pg wood were less than that of Pp wood. N-fertilization reduced root biomass of Pg more than of Pp, but increased leaf biomass, leaf area, A, and PNUEi of Pg more than of Pp. Among 13 genes involved in the transport of ammonium or nitrate or in N assimilation, transcripts showed more pronounced changes to N-fertilization in Pg than in Pp. Increases in NR activities and N contents due to N-fertilization were larger in Pg than in Pp. In both species, N-fertilization resulted in lower calorific values as well as shorter and wider vessel elements/fibres. These results suggest that growth, carbon and N physiology, and wood properties are more sensitive to increasing N availability in fast-growing poplars than in slow-growing ones, which is probably due to prioritized resource allocation to the leaves and accelerated N physiological processes in fast-growing poplars under higher N levels.