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Title: Genotype-specific responses of Bromus erectus to elevated CO{sub 2} at different levels of biodiversity and endophyte infection - a field experiment

Abstract

In 1994 we initiated a long-term field experiment in a calcareous grassland to study the effects of elevated CO{sub 2} on individuals, populations, and communities. Clonal replicates of 54 genotypes of the dominant grass Bromus erectus were grown in communities planted at three levels of biodiversity (5-, 12-, 31-species plots) and exposed to ambient and elevated CO{sub 2}. The same genotypes were also individually grown in tubes within the field plots. Some genotypes were infected by the endophytic fungus Epichloee typhina. Elevated CO{sub 2} had no significant effects on plant growth, however, there was large variation among genotypes in all measured characters. A significant CO{sub 2}-by-genotype interaction was found for leaf length in the competition-free tubes. Infection by the endophyte led to the abortion of all inflorescences but increased vegetative growth, especially under competitive conditions.

Authors:
; ;  [1]
  1. Univ. of Basel (Switzerland)|[Univ. of Zurich (Switzerland)
Publication Date:
OSTI Identifier:
95887
Report Number(s):
CONF-9507129-
Journal ID: BECLAG; ISSN 0012-9623; TRN: 95:004728-0155
Resource Type:
Journal Article
Resource Relation:
Journal Name: Bulletin of the Ecological Society of America; Journal Volume: 76; Journal Issue: 2; Conference: 80. anniversary of the transdisciplinary nature of ecology, Snowbird, UT (United States), 30 Jul - 3 Aug 1995; Other Information: PBD: Jun 1995
Country of Publication:
United States
Language:
English
Subject:
56 BIOLOGY AND MEDICINE, APPLIED STUDIES; GRAMINEAE; GENETIC VARIABILITY; RESPONSE MODIFYING FACTORS; CARBON DIOXIDE; ECOLOGICAL CONCENTRATION; BIOLOGICAL EFFECTS; SPECIES DIVERSITY; FUNGAL DISEASES

Citation Formats

Steinger, T., Groppe, K., and Schmid, B. Genotype-specific responses of Bromus erectus to elevated CO{sub 2} at different levels of biodiversity and endophyte infection - a field experiment. United States: N. p., 1995. Web.
Steinger, T., Groppe, K., & Schmid, B. Genotype-specific responses of Bromus erectus to elevated CO{sub 2} at different levels of biodiversity and endophyte infection - a field experiment. United States.
Steinger, T., Groppe, K., and Schmid, B. 1995. "Genotype-specific responses of Bromus erectus to elevated CO{sub 2} at different levels of biodiversity and endophyte infection - a field experiment". United States. doi:.
@article{osti_95887,
title = {Genotype-specific responses of Bromus erectus to elevated CO{sub 2} at different levels of biodiversity and endophyte infection - a field experiment},
author = {Steinger, T. and Groppe, K. and Schmid, B.},
abstractNote = {In 1994 we initiated a long-term field experiment in a calcareous grassland to study the effects of elevated CO{sub 2} on individuals, populations, and communities. Clonal replicates of 54 genotypes of the dominant grass Bromus erectus were grown in communities planted at three levels of biodiversity (5-, 12-, 31-species plots) and exposed to ambient and elevated CO{sub 2}. The same genotypes were also individually grown in tubes within the field plots. Some genotypes were infected by the endophytic fungus Epichloee typhina. Elevated CO{sub 2} had no significant effects on plant growth, however, there was large variation among genotypes in all measured characters. A significant CO{sub 2}-by-genotype interaction was found for leaf length in the competition-free tubes. Infection by the endophyte led to the abortion of all inflorescences but increased vegetative growth, especially under competitive conditions.},
doi = {},
journal = {Bulletin of the Ecological Society of America},
number = 2,
volume = 76,
place = {United States},
year = 1995,
month = 6
}
  • Root acid phosphatase activity increases phosphate available to plants by cleaving phosphate esters in soil organic matter. Because of increased plant growth potential under elevated [CO{sub 2}], we hypothesized that high [CO{sub 2}]-grown plants might exhibit higher phosphatase activity than low [CO{sub 2}]-grown plants. We assayed phosphatase activity in two species grown on two substrates (Bromus on serpentine soil and Bromus and Avena on sandstone soil) under high and low [CO{sub 2}] and under several nutrient treatments. Phosphatase activity was expressed per gram fresh weight of roots. Phosphatase activity of Bromus roots (on sandstone) was first assayed in treatments wheremore » only P and K, or only N, were added to soil. Bromus roots in this case showed strong induction of phosphatase activity when N only had been added to soil, indicating that Bromus regulated its phosphatase activity in response to phosphate availability. Both Bromus and Avena growing in sandstone, and Bromus growing in serpentine, showed enhanced phosphatase activity at high nutrient (N, P, and K) levels over that at low nutrient levels, but no differences between phosphatase activity were apparent between [CO{sub 2}] treatments. The increased phosphatase activity at high N, P, and K may indicate enhanced {open_quotes}growth demand{close_quotes} (reflected in higher biomass) in both Avena and Bromus. In contrast, though Bromus {open_quotes}growth demand{close_quotes} (biomass) increased under high [CO{sub 2}] on sandstone, phosphatase activity did not increase.« less
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