Abstract
The incorporation of chicory into phased farming systems requires an understanding of N mineralisation of chicory residues and the supply of N to subsequent crops. A field experiment was conducted to determine the relative rates of N mineralisation from chicory, chicory/subclover and lucerne/subclover residues. Existing pastures were removed by spraying with herbicide in either spring or autumn and mineral N was measured at the time of spraying, and then 6 and 12 months later. Chicory/subclover had the greatest mineralisation rate during the first 6 months after spraying in either spring (0.54 kg mineral N/ha/day) or autumn (0.64 kg mineral N/ha/day), whilst lucerne/subclover had the lowest at 0.07 and 0.08 kg mineral N/ha/day for spring and autumn, respectively. However, 12 months after spraying, the mineralisation rate increased for lucerne/subclover, but began to slow for chicory and chicory/subclover. Compared to chicory alone, growing chicory with subclover significantly increased the release of mineral N by 28 and 47 kg N/ha, 6 and 12 months after pasture removal, respectively. The mass of N mineralised 12 months after pasture removal was similar for chicory/subclover (219 kg N/ha) and lucerne/subclover (234 kg N/ha). However, as high rates of mineralisation occurred for chicory treatments within the first 6 months after spraying, chicory-based pastures could potentially be sprayed out later (eg autumn) than lucerne pastures allowing more grazing time without the risk of N deficiency to the following crop. Therefore chicory/subclover pastures are well suited to phased farming systems, particularly where pasture phases are shorter, as the N benefit can be readily utilised by following crops.
Original language | English |
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Title of host publication | 16th AAC |
Subtitle of host publication | Capturing opportunities and overcoming obstacles in Australian agronomy |
Editors | I. Yunusa |
Place of Publication | Australia |
Publisher | The Regional Institute |
Pages | 1-5 |
Number of pages | 5 |
Publication status | Published - 2012 |
Event | 16th Australian Agronomy Conference - University of New England, Armidale, Australia Duration: 14 Oct 2012 → 18 Oct 2012 Conference number: 16th http://agronomyaustraliaproceedings.org/index.php/2012-conf-proc-homepage (Conference proceedings 2012 homepage) |
Conference
Conference | 16th Australian Agronomy Conference |
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Abbreviated title | Capturing Opportunities and Overcoming Obstacles in Australian Agronomy |
Country/Territory | Australia |
City | Armidale |
Period | 14/10/12 → 18/10/12 |
Internet address |
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