Benefits from below: silicon supplementation maintains legume productivity under predicted climate change scenarios

Johnson, Scott N. and Ryalls, James M. W. and Gherlenda, Andrew N. and Frew, Adam ORCID: and Hartley, Susan E. (2018) Benefits from below: silicon supplementation maintains legume productivity under predicted climate change scenarios. Frontiers in Plant Science, 9:202. pp. 1-9.

Text (Published Version)
Available under License Creative Commons Attribution 4.0.

Download (1MB) | Preview


Many studies demonstrate that elevated atmospheric carbon dioxide concentrations (eCO2) can promote root nodulation and biological nitrogen fixation (BNF) in legumes such as lucerne (Medicago sativa). But when elevated temperature (eT) conditions are applied in tandem with eCO2, a more realistic scenario for future climate change, the positive effects of eCO2 on nodulation and BNF in M. sativa are often much reduced. Silicon (Si) supplementation of M. sativa has also been reported to promote root nodulation and BNF, so could potentially restore the positive effects of eCO2 under eT. Increased nitrogen availability, however, could also increase host suitability for aphid pests, potentially negating any benefit. We applied eCO2 (+240 ppm) and eT (+4°C), separately and in combination, to M. sativa growing in Si supplemented (Si+) and un-supplemented soil (Si-) to determine whether Si moderated the effects of eCO2 and eT. Plants were either inoculated with the aphid Acyrthosiphon pisum or insect-free. In Si- soils, eCO2 stimulated plant growth by 67% and nodulation by 42%, respectively, whereas eT reduced these parameters by 26 and 48%, respectively. Aphids broadly mirrored these effects on Si- plants, increasing colonization rates under eCO2 and performing much worse (reduced abundance and colonization) under eT when compared to ambient conditions, confirming our hypothesized link between root nodulation, plant growth, and pest performance. Examined across all CO2 and temperature regimes, Si supplementation promoted plant growth (+93%), and root nodulation (+50%). A. pisum abundance declined sharply under eT conditions and was largely unaffected by Si supplementation. In conclusion, supplementing M. sativa with Si had consistent positive effects on plant growth and nodulation under different CO2 and temperature scenarios. These findings offer potential for using Si supplementation to maintain legume productivity under predicted climate change scenarios without making legumes more susceptible to insect pests.

Statistics for USQ ePrint 37293
Statistics for this ePrint Item
Item Type: Article (Commonwealth Reporting Category C)
Refereed: Yes
Item Status: Live Archive
Faculty/School / Institute/Centre: No Faculty
Faculty/School / Institute/Centre: No Faculty
Date Deposited: 20 Nov 2019 05:54
Last Modified: 07 Jun 2021 00:23
Uncontrolled Keywords: alfalfa, aphids, atmospheric change, climate change, global warming, silica, silicon
Fields of Research (2008): 06 Biological Sciences > 0607 Plant Biology > 060799 Plant Biology not elsewhere classified
05 Environmental Sciences > 0502 Environmental Science and Management > 050205 Environmental Management
05 Environmental Sciences > 0501 Ecological Applications > 050101 Ecological Impacts of Climate Change
Fields of Research (2020): 31 BIOLOGICAL SCIENCES > 3108 Plant biology > 310899 Plant biology not elsewhere classified
41 ENVIRONMENTAL SCIENCES > 4104 Environmental management > 410404 Environmental management
41 ENVIRONMENTAL SCIENCES > 4101 Climate change impacts and adaptation > 410102 Ecological impacts of climate change and ecological adaptation
Socio-Economic Objectives (2008): D Environment > 96 Environment > 9609 Land and Water Management > 960904 Farmland, Arable Cropland and Permanent Cropland Land Management
Identification Number or DOI:

Actions (login required)

View Item Archive Repository Staff Only