TY - JOUR
T1 - Anatomical characteristics of individual roots within the fine-root architecture of Chamaecyparis obtusa (Sieb. & Zucc.) in organic and mineral soil layers
AU - Hishi, Takuo
AU - Tateno, Ryunosuke
AU - Takeda, Hiroshi
N1 - Funding Information:
Acknowledgment We thank Koji Kawamura, Reiji Fujimaki, and members of the Laboratory of Forest Ecology at Kyoto University for helpful comments. Staff of the Kamigamo Experimental Station kindly granted us permission to conduct the field studies. This study was partly supported by a Grant-in-Aid for the 21st century COE program for Innovative Food and Environmental Studies Pioneered by Entomomimetic Sciences, from the Ministry of Education, Culture, Sports, Science and Technology of Japan.
PY - 2006/9
Y1 - 2006/9
N2 - Nutrient availability and temporal variation of physical stress are usually higher in organic soil layers than in mineral soils. Individual roots within the fine-root system adjust anatomical, morphological, and turnover characteristics to soil conditions, for example nutrient availability and physical stresses. We investigated anatomical traits, including cork formation and passage and protoxylem cell numbers, in cross-sections of individual fine roots of the conifer Chamaecyparis obtusa (Siebold & Zucc.) growing under different soil conditions. The fine-root systems in different soil layers were compared by sampling ingrowth cores buried for 1 year and filled with organic and mineral soil substrates. The number of exodermal passage cells was lower in roots from organic soils than in those from mineral soils, suggesting that apical roots tend to be more stress-tolerant in the organic layer than in mineral soils. In contrast, both root tip and specific root tip density were higher in roots from organic soils than in those from mineral soil layers. The proportion of roots with two strands of protoxylem (diarch) was greater in organic (90%) than in mineral (25%) soils. Thus, although the absorptivity of individual apical roots decreases in organic layers, the absorptivity of the entire fine-root system of C. obtusa may be increased as a result of the increase in apical root density and the proportion of ephemeral roots. We found that the fine-root system had simultaneous plasticity in density, anatomy, and architecture in response to complex soil conditions.
AB - Nutrient availability and temporal variation of physical stress are usually higher in organic soil layers than in mineral soils. Individual roots within the fine-root system adjust anatomical, morphological, and turnover characteristics to soil conditions, for example nutrient availability and physical stresses. We investigated anatomical traits, including cork formation and passage and protoxylem cell numbers, in cross-sections of individual fine roots of the conifer Chamaecyparis obtusa (Siebold & Zucc.) growing under different soil conditions. The fine-root systems in different soil layers were compared by sampling ingrowth cores buried for 1 year and filled with organic and mineral soil substrates. The number of exodermal passage cells was lower in roots from organic soils than in those from mineral soils, suggesting that apical roots tend to be more stress-tolerant in the organic layer than in mineral soils. In contrast, both root tip and specific root tip density were higher in roots from organic soils than in those from mineral soil layers. The proportion of roots with two strands of protoxylem (diarch) was greater in organic (90%) than in mineral (25%) soils. Thus, although the absorptivity of individual apical roots decreases in organic layers, the absorptivity of the entire fine-root system of C. obtusa may be increased as a result of the increase in apical root density and the proportion of ephemeral roots. We found that the fine-root system had simultaneous plasticity in density, anatomy, and architecture in response to complex soil conditions.
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U2 - 10.1007/s11284-006-0184-8
DO - 10.1007/s11284-006-0184-8
M3 - Article
AN - SCOPUS:33748420815
VL - 21
SP - 754
EP - 758
JO - Ecological Research
JF - Ecological Research
SN - 0912-3814
IS - 5
ER -