Arbuscular mycorrhizal fungi benefit from 7 years of free air CO2 enrichment in well-fertilized grass and legume monocultures

被引:37
作者
Gamper, H
Peter, M
Jansa, J
Lüscher, A
Hartwig, UA
Leuchtmann, A
机构
[1] ETH, Swiss Fed Inst Technol, Geobot Inst, CH-8008 Zurich, Switzerland
[2] Swiss Fed Res Stn Agroecol & Agr, CH-8046 Zurich, Switzerland
[3] ETH, Swiss Fed Inst Technol, Inst Plant Sci, CH-8315 Lindau, Switzerland
[4] Acad Engiadina, CH-7503 Samedan, Switzerland
关键词
arbuscular mycorrhiza; free air carbon dioxide enrichment (FACE); Lolium perenne (perennial ryegrass); nitrogen fertilization; root colonization; spore abundance; Trifolium repens (white clover);
D O I
10.1111/j.1529-8817.2003.00734.x
中图分类号
X176 [生物多样性保护];
学科分类号
090705 ;
摘要
Rising atmospheric carbon dioxide partial pressure (pCO(2)) and nitrogen (N) deposition are important components of global environmental change. In the Swiss free air carbon dioxide enrichment (FACE) experiment, the effect of altered atmospheric pCO(2) (35 vs. 60 Pa) and the influence of two different N-fertilization regimes (14 vs. 56 g N m(-2) a(-1)) on root colonization by arbuscular mycorrhizal fungi (AMF) and other fungi (non-AMF) of Lolium perenne and Trifolium repens were studied. Plants were grown in permanent monoculture plots, and fumigated during the growth period for 7 years. At elevated pCO(2) AMF and non-AMF root colonization was generally increased in both plant species, with significant effects on colonization intensity and on hyphal and non-AMF colonization. The CO2 effect on arbuscules was marginally significant (P=0.076). Moreover, the number of small AMF spores (less than or equal to100 mum) in the soils of monocultures (at low-N fertilization) of both plant species was significantly increased, whereas that of large spores (>100 mum) was increased only in L. perenne plots. N fertilization resulted in a significant decrease of root colonization in L. perenne, including the AMF parameters, hyphae, arbuscules, vesicles and intensity, but not in T. repens. This phenomenon was probably caused by different C-sink limitations of grass and legume. Lacking effects of CO2 fumigation on intraradical AMF structures (under high-N fertilization) and no response to N fertilization of arbuscules, vesicles and colonization intensity suggest that the function of AMF in T. repens was non-nutritional. In L. perenne, however, AM symbiosis may have amended N nutrition, because all root colonization parameters were significantly increased under low-N fertilization, whereas under high-N fertilization only vesicle colonization was increased. Commonly observed P-nutritional benefits from AMF appeared to be absent under the phosphorus-rich soil conditions of our field experiment. We hypothesize that in well-fertilized agricultural ecosystems, grasses benefit from improved N nutrition and legumes benefit from increased protection against pathogens and/or herbivores. This is different from what is expected in nutritionally limited plant communities.
引用
收藏
页码:189 / 199
页数:11
相关论文
共 69 条
[1]  
[Anonymous], 2002, MYCORRHIZAL ECOLOGY
[2]   Differential contribution of arbuscular mycorrhizal fungi to plant nitrate uptake (15N) under increasing N supply to the soil [J].
Azcón, R. ;
Ruiz-Lozano, J.M. ;
Rodríguez, R. .
Canadian Journal of Botany, 2001, 79 (10) :1175-1180
[3]   Root system adjustments:: regulation of plant nutrient uptake and growth responses to elevated CO2 [J].
BassiriRad, H ;
Gutschick, VP ;
Lussenhop, J .
OECOLOGIA, 2001, 126 (03) :305-320
[4]   THE RESPONSE OF NATURAL ECOSYSTEMS TO THE RISING GLOBAL CO2 LEVELS [J].
BAZZAZ, FA .
ANNUAL REVIEW OF ECOLOGY AND SYSTEMATICS, 1990, 21 :167-196
[5]   Influences of anthropogenic pollution on mycorrhizal fungal communities [J].
Cairney, JWG ;
Meharg, AA .
ENVIRONMENTAL POLLUTION, 1999, 106 (02) :169-182
[6]   Dry matter yield, leaf growth and population dynamics in Lolium perenne Trifolium repens-dominated pasture turves exposed to two levels of elevated CO2 [J].
Clark, H ;
Newton, PCD ;
Bell, CC ;
Glasgow, EM .
JOURNAL OF APPLIED ECOLOGY, 1997, 34 (02) :304-316
[7]   Nitrogen fertilization and developmental stage alter the response of Lolium perenne to elevated CO2 [J].
Daepp, M ;
Nösberger, J ;
Lüscher, A .
NEW PHYTOLOGIST, 2001, 150 (02) :347-358
[8]  
Daniels B. A., 1982, Methods and principles of mycorrhizal research., P29
[9]  
Dirks B., 1930, Landwirtschaftl. Jahrbucher, V71, P73
[10]  
Egerton-Warburton LM, 2000, ECOL APPL, V10, P484, DOI 10.1890/1051-0761(2000)010[0484:SIAMCA]2.0.CO