Silicon uptake by a pasture grass experiencing simulated grazing is greatest under elevated precipitation
Abstract Background Grasses are hyper-accumulators of silicon (Si) and often up-regulate Si following herbivory. Positive correlations exist between Si and plant water content, yet the extent to which Si uptake responses can be mediated by changes in soil water availability has rarely been studied a...
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| Format: | Article |
| Language: | English |
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BMC
2018-12-01
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| Series: | BMC Ecology |
| Subjects: | |
| Online Access: | http://link.springer.com/article/10.1186/s12898-018-0208-6 |
| _version_ | 1818737926839730176 |
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| author | James M. W. Ryalls Ben D. Moore Scott N. Johnson |
| author_facet | James M. W. Ryalls Ben D. Moore Scott N. Johnson |
| author_sort | James M. W. Ryalls |
| collection | DOAJ |
| description | Abstract Background Grasses are hyper-accumulators of silicon (Si) and often up-regulate Si following herbivory. Positive correlations exist between Si and plant water content, yet the extent to which Si uptake responses can be mediated by changes in soil water availability has rarely been studied and never, to our knowledge, under field conditions. We used field-based rain-exclusion shelters to investigate how simulated grazing (shoot clipping) and altered rainfall patterns (drought and elevated precipitation, representing 50% and 150% of ambient precipitation levels, respectively) affected initial patterns of root- and shoot-Si uptake in a native Australian grass (Microlaena stipoides) in Si-supplemented and untreated soils. Results Si supplementation increased soil water retention under ambient and elevated precipitation but not under drought, although this had little effect on Si uptake and growth (tiller numbers or root biomass) of M. stipoides. Changes in rainfall patterns and clipping had strong individual effects on plant growth and Si uptake and storage, whereby clipping increased Si uptake by M. stipoides under all rainfall treatments but to the greatest extent under elevated precipitation. Moreover, above-ground–below-ground Si distribution only changed following elevated precipitation by decreasing the ratio of root:shoot Si concentrations. Conclusions Results highlight the importance of soil water availability for Si uptake and suggest a role for both active and passive Si transport mechanisms. Such manipulative field studies may provide a more realistic insight into how grasses initially respond to herbivory in terms of Si-based defence under different environmental conditions. |
| first_indexed | 2024-12-18T01:00:49Z |
| format | Article |
| id | doaj.art-a7377ce12ad34410b4b51051e001df06 |
| institution | Directory Open Access Journal |
| issn | 1472-6785 |
| language | English |
| last_indexed | 2024-12-18T01:00:49Z |
| publishDate | 2018-12-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Ecology |
| spelling | doaj.art-a7377ce12ad34410b4b51051e001df062022-12-21T21:26:23ZengBMCBMC Ecology1472-67852018-12-011811810.1186/s12898-018-0208-6Silicon uptake by a pasture grass experiencing simulated grazing is greatest under elevated precipitationJames M. W. Ryalls0Ben D. Moore1Scott N. Johnson2Hawkesbury Institute for the Environment, Western Sydney UniversityHawkesbury Institute for the Environment, Western Sydney UniversityHawkesbury Institute for the Environment, Western Sydney UniversityAbstract Background Grasses are hyper-accumulators of silicon (Si) and often up-regulate Si following herbivory. Positive correlations exist between Si and plant water content, yet the extent to which Si uptake responses can be mediated by changes in soil water availability has rarely been studied and never, to our knowledge, under field conditions. We used field-based rain-exclusion shelters to investigate how simulated grazing (shoot clipping) and altered rainfall patterns (drought and elevated precipitation, representing 50% and 150% of ambient precipitation levels, respectively) affected initial patterns of root- and shoot-Si uptake in a native Australian grass (Microlaena stipoides) in Si-supplemented and untreated soils. Results Si supplementation increased soil water retention under ambient and elevated precipitation but not under drought, although this had little effect on Si uptake and growth (tiller numbers or root biomass) of M. stipoides. Changes in rainfall patterns and clipping had strong individual effects on plant growth and Si uptake and storage, whereby clipping increased Si uptake by M. stipoides under all rainfall treatments but to the greatest extent under elevated precipitation. Moreover, above-ground–below-ground Si distribution only changed following elevated precipitation by decreasing the ratio of root:shoot Si concentrations. Conclusions Results highlight the importance of soil water availability for Si uptake and suggest a role for both active and passive Si transport mechanisms. Such manipulative field studies may provide a more realistic insight into how grasses initially respond to herbivory in terms of Si-based defence under different environmental conditions.http://link.springer.com/article/10.1186/s12898-018-0208-6ClippingDroughtGrassesSiliconSimulated herbivoryWater stress |
| spellingShingle | James M. W. Ryalls Ben D. Moore Scott N. Johnson Silicon uptake by a pasture grass experiencing simulated grazing is greatest under elevated precipitation BMC Ecology Clipping Drought Grasses Silicon Simulated herbivory Water stress |
| title | Silicon uptake by a pasture grass experiencing simulated grazing is greatest under elevated precipitation |
| title_full | Silicon uptake by a pasture grass experiencing simulated grazing is greatest under elevated precipitation |
| title_fullStr | Silicon uptake by a pasture grass experiencing simulated grazing is greatest under elevated precipitation |
| title_full_unstemmed | Silicon uptake by a pasture grass experiencing simulated grazing is greatest under elevated precipitation |
| title_short | Silicon uptake by a pasture grass experiencing simulated grazing is greatest under elevated precipitation |
| title_sort | silicon uptake by a pasture grass experiencing simulated grazing is greatest under elevated precipitation |
| topic | Clipping Drought Grasses Silicon Simulated herbivory Water stress |
| url | http://link.springer.com/article/10.1186/s12898-018-0208-6 |
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