[Interactive effects of light intensity and nitrogen supply on fraxinus mandshurica seedlings growth, biomass, and nitrogen allocation].
With sand culture in greenhouse, the responses of Fraxinus mandshurica seedlings growth, biomass, and N allocation to 2 levels of light intensity and 4 levels of N supply were studied. The results showed that under low light intensity, the seedlings shoot/root ratio (S/R) and net N uptake rate (NNUR) increased significantly (P < 0.01), but their relative growth rate (RGR) and net assimilation rate (NAR) had a significant decrease (P < 0.01). The biomass of root, stem, leaf, and total plant under low light was decreased by 36.8% (P < 0.01), 1.7%, 12.7% (P < 0.05) , and 24.3% (P < 0.01), respectively, and the N allocation to leaf increased but that to root was in adverse. At the two light levels, N supply had an obvious promotion effect on the seedlings growth, and the S/R and the N allocation to leaf were increased obviously with increasing N supply. Significant interactive effects of light and N supply were observed on the seedlings diameter, S/R, RGR, and biomass allocation.
Huo
Chang-fu
CF
School of Forestry, Northeast Forestry University, Har-bin, China. huochangfu@163.com
Wang
Zheng-quan
ZQ
Sun
Hai-long
HL
Fan
Zhi-qiang
ZQ
Zhao
Xiao-min
XM
D018533:Biomass; D031661:Fraxinus / Q000254:growth & development* / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism / Q000494:pharmacology*; D036226:Seedlings / Q000254:growth & development* / Q000378:metabolism; D013472:Sunlight
D009584:Nitrogen