Journal Article

N-fertilization has different effects on the growth, carbon and nitrogen physiology, and wood properties of slow- and fast-growing Populus species

Qu, Long, Polle, Andrea, Bai, Hua, Jiang, Xiangning, Peng, Changhui, Gai, Ying, Luo, Zhi-Bin, Li, Hong, Luo, Jie, Li, Mengchun, Janz, Dennis, Cao, Xu, Liu, Tongxian

2012

Overview

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. alba×P. glandulosa, Pg) poplar saplings were exposed to different N levels. Above-ground biomass, leaf area, photosynthetic rates (A), instantaneous photosynthetic nitrogen use efficiency (PNUE i), 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.

• Publisher: Oxford University Press [etc.],Oxford University Press
• Subject: aboveground biomass / Agronomy. Soil science and plant productions / ammonium compounds / analysis / Biological and medical sciences / Biological Transport / Biomass / carbon / Carbon - metabolism / chlorophyll / Fundamental and applied biological sciences. Psychology / General agronomy. Plant production / genes / genetics / Glutamate Synthase / Glutamate Synthase - metabolism / glutamic acid / growth & development / leaf area / leaves / lignin / Lignin - analysis / metabolism / nitrate reductase / Nitrate Reductase - metabolism / nitrates / Nitrates - metabolism / nitrogen / Nitrogen - metabolism / Nitrogen, phosphorus, potassium fertilizations / nutrient use efficiency / photosynthesis / Photosynthesis - physiology / physiology / Plant Leaves / Plant Leaves - genetics / Plant Leaves - growth & development / Plant Leaves - physiology / Plant Leaves - ultrastructure / Plant physiology and development / Plant Proteins / Plant Proteins - metabolism / Plant Roots / Plant Roots - genetics / Plant Roots - growth & development / Plant Roots - physiology / Plant Roots - ultrastructure / Plant Shoots / Plant Shoots - genetics / Plant Shoots - growth & development / Plant Shoots - physiology / Plant Shoots - ultrastructure / Plant Stems / Plant Stems - genetics / Plant Stems - growth & development / Plant Stems - physiology / Plant Stems - ultrastructure / Plant Transpiration / Plant Transpiration - physiology / Populus / Populus - genetics / Populus - growth & development / Populus - physiology / Populus - ultrastructure / Quaternary Ammonium Compounds / Quaternary Ammonium Compounds - metabolism / Research Paper / resource allocation / saplings / shoots / Soil / Soil-plant relationships. Soil fertility. Fertilization. Amendments / Species Specificity / sugars / ultrastructure / wood / Wood - growth & development / wood properties / Xylem / Xylem - genetics / Xylem - growth & development / Xylem - physiology / Xylem - ultrastructure / xylem vessels