Weed–pathogen interactions and elevated CO2: growth changes in favour of the biological control agent. (13th March 2014)

• Record Type: Journal Article
• Authors: Shabbir, A; Dhileepan, K; Khan, N; Adkins, S W; Bailey, Karen
• Is Part Of: Weed research. Volume 54:Number 3(2014:Jun.)
• Page Start: 217
• Page End: 222
• Publication Date: 2014-03-13
• Subjects: Weeds -- Control -- Periodicals; Herbicides -- Periodicals; 632.5
• DOI: 10.1111/wre.12078
• Languages: English
• ISSNs: 0043-1737

Abstract

<abstract abstract-type="main" id="wre12078-abs-0001"> <title>Summary</title> <p>In this study, we used <italic>Parthenium hysterophorus</italic> and one of its biological control agents, the winter rust (<italic>Puccinia abrupta</italic> var. <italic>partheniicola</italic>) as a model system to investigate how the weed may respond to infection under a climate change scenario involving an elevated atmospheric CO<sub>2</sub> (550 <italic>μ</italic>mol mol<sup>−1</sup>) concentration. Under such a scenario, <italic>P. hysterophorus</italic> plants grew significantly taller (52%) and produced more biomass (55%) than under the ambient atmospheric CO<sub>2</sub> concentration (380 <italic>μ</italic>mol mol<sup>−1</sup>). Following winter rust infection, biomass production was reduced by 17% under the ambient and by 30% under the elevated atmospheric CO<sub>2</sub> concentration. The production of branches and leaf area was significantly increased by 62% and 120%, under the elevated as compared with ambient CO<sub>2</sub> concentration, but unaffected by rust infection under either condition. The photosynthesis and water use efficiency (WUE) of <italic>P. hysterophorus</italic> plants were increased by 94% and 400%, under the elevated as compared with the ambient atmospheric CO<sub>2</sub> concentration. However, in the rust‐infected plants, the photosynthesis and WUE decreased by 18% and 28%, respectively, under the elevated CO<sub>2</sub> and were unaffected by the ambient atmospheric CO<sub>2</sub> concentration. The results suggest that although <italic>P. hysterophorus</italic> will benefit from a future climate involving an elevation of the atmospheric CO<sub>2</sub> concentration, it is also likely that the winter rust will perform more effectively as a biological control agent under these same conditions.</p> </abstract>