摘要:
以北京西山、北京延庆、山东泰山和山西绛县4 个产地的黄栌幼苗为材料,研究了田间模拟试验条件下苗木
根系对土壤水分胁迫的短期形态响应。结果表明:1) 黄栌幼苗通过调整根系形态以适应持续干旱环境,持续重度
胁迫环境中生长的幼苗根尖数量、根系分枝数量、根系表面积以及平均根系直径分别比对照平均高46.5%、
15.5%、3.4%、8.6%,且分别比持续中度胁迫环境中生长的幼苗平均高90.5%、34.2%、15.6%、18.4%。2) 4 产
地持续干旱环境中幼苗的0.0 ~0.5 mm 根系长度和根尖数量分别占总量的54.7% ~93.5%和95.1% ~99.5%,因
此,0.0 ~0.5 mm 细根对干旱胁迫的反应比其他径级根系更为敏感。3) 恢复灌溉后,不同产地黄栌幼苗根系生长
的恢复能力存在明显差异。山西绛县幼苗根系生物量的相对生长量在中度胁迫复水后分别是北京西山和北京延
庆幼苗的29.0 和48.6 倍,在重度胁迫后恢复灌溉则比北京西山幼苗高280%,因而表现出极强的敏感性和生长恢
复能力。
关键词:
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黄栌
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根系形态
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干旱胁迫
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恢复灌溉
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华北
Abstract:
Short-term responses of root morphology to soil drought stress in Cotinus coggyria seedlings gathered
from four locations in northern China ( Xishan Mountain and Yanqing County in Beijing, Taishan
Mountain in Shandong Province and Jiangxian County in Shanxi Province) were studied in the field. The
results indicated that: 1) C. coggyria seedlings adapted to continuous drought stress by altering their root
morphology. The root tip number, root fork number, root surface area and average root diameter of C.
coggyria seedlings treated with severe stress were higher than those of control by 46.5%, 15.5%,
3.4%, 8.6%, respectively, and they were also higher than those of seedlings continuously treated with
moderate stress by 90.5%, 34.2%, 15.6%, 18.4%, respectively. 2) Fine roots at a diameter of
0.0 ~0.5 mm were more sensitive to soil water stress than any other sizes of roots, presented as the
length and tip number of fine roots increased, accounting for 54.7% ~93.5% and 95.1% ~99.5% of
total root during continuous drought stress treatments. 3) The recovery growth of roots after restoring
irrigation in seedlings from four different locations was remarkably different. The relative root biomass of
seedlings from Jiangxian County of Shanxi Province subjecting to the moderate drought stress treatment
and then restoring irrigation was 29.0 and 48.6 times of those of seedlings from Xishan Mountain andYanqing County of Beijing, and it was 280% higher than that of seedlings from Xishan Mountain of
Beijing when subjecting to severe drought stress and then restoring irrigation. Thus, the seedlings from
Jiangxian County of Shanxi Province are more sensitive to soil drought stress, but they have stronger
recovery ability after restoring irrigation than others.
百度学术
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