17 Feb 2016
Results of 2015 HRZ Nutrition Experiments
Summary of responses from nutrient omission experiments.
![](http://media.ipni.net/image/IPNI2016RNO10-1528-P.jpg)
Summary of results
The 2015 wheat trials at Bool Lagoon and Glenthompson showed an early biomass response to N and P by anthesis, but this did not translate into higher grain yield (see Table). There was evidence that additional P led to a reduced harvest index and lower grain size, which is consistent with the crop haying off under dry soil conditions during the grain-fill period. The 2015 canola trials showed a strong response in all measured parameters to additional N at Frances and both N and P at Inverleigh. There were positive grain yield and HI responses to S in wheat at Bool Lagoon in 2015, but negative responses to S at anthesis in wheat at Glenthompson (2015). Across all sites there wa only one significant response to micronutrients, which was for wheat (grain) at Glenthompson, and did not translate to a higher grain yield.
Summary of significant effects of applied nutrients in the 2015 omission trials. Values separated by different letters are significantly different at the 5% level. For N effects, 2 lsd’s are shown. The first is for comparison between the lowest and middle rate, the second for comparisons between the middle and highest rate. This is because the lowest N rate was only applied to the Nil and +all treatments, whereas the middle and highest N rate were applied to all treatments.
Site | Parameter | Response to… | Description of significant differences | 5% lsd | |
Frances (canola) | Grain yield (t/ha, 100 C drying) | N | 18 kg N/ha | 0.64b | 0.163 |
95 kg N/ha | 0.89a | 0.126 | |||
174 kg N/ha | 0.94a | ||||
![]() | Biomass – 11 September (kg/ha) | N | 18 kg N/ha | 2326b | 660 |
95 kg N/ha | 2632b | 461 | |||
174 kg N/ha | 3396a | ||||
![]() | Harvest Index | Not significant | ![]() | 0.243 | ![]() |
![]() | Biomass at grain harvest (t/ha) | N | 18 kg N/ha | 2.76c | 0.52 |
95 kg N/ha | 3.62b | 0.40 | |||
174 kg N/ha | 4.04a | ||||
Bool Lagoon (wheat) | Grain yield (t/ha, 100 C drying) | N, S | 18 kg N/ha | 3.50a | 0.459 |
64 kg N/ha | 3.05b | 0.320 | |||
149 kg N/ha | 3.45a | ||||
0 kg S/ha | 3.12b | 0.356 | |||
23 kg S/ha | 3.55a | ||||
Visual rating 28 Oct (scored 1-5) | N, P | 18 kg N/ha | 1.50c | 0.334 | |
64 kg N/ha | 1.76b | 0.233 | |||
149 kg N/ha | 1.99a | ||||
0 kg P/ha | 1.54b | 0.260 | |||
25 kg P/ha | 1.97a | ||||
![]() | Biomass at grain harvest (t/ha) | P | 0 kg P/ha | 7.67b | 0.396 |
25 kg P/ha | 8.42a | ![]() | |||
![]() | Harvest index | P, S | 0 kg P/ha | 0.456a | 0.0337 |
30 kg P/ha | 0.421b | ![]() | |||
0 kg S/ha | 0.377b | 0.0337 | |||
23 kg S/ha | 0.439a | ![]() |
Site | Parameter | Response to… | Description of significant differences | 5% lsd | |
Glenthompson (wheat) | Grain yield (t/ha, 100 C drying) | Not significant | 4.32 | ||
![]() | Harvest Index | Not significant | 0.41 | ||
![]() | Grain protein (%) | Not significant | 13.0 | ||
![]() | Grain weight (g/1000 grain) | P (P = 0.09) | 0 kg P/ha | 33.2a | 1.53 |
25 kg P/ha | 31.9b | ||||
![]() | Anthesis biomass – 23 October (kg/ha) | N, P
S (P = 0.08) | 18 kg N/ha | 9369b | 438 |
77 kg N/ha | 9807a | ||||
0 kg P/ha | 9033b | 534 | |||
25 kg P/ha | 9688a | ||||
0 kg S/ha | 10007 | 534 | |||
23 kg S/ha | 9449 | ||||
![]() | Ear density – 23 October (ears/m2) | P | 0 kg P/ha | 425b | 30.3 |
25 kg P/ha | 463a | ||||
![]() | Flag leaf mass – October (g/m2) | N | 18 kg N/ha | 18.7b | 1.31 |
77 kg N/ha | 21.5a | ||||
![]() | Biomass at grain harvest (t/ha) | Micronutrients (P = 0.1) | None | 10.6 | 0.69 |
+Cu, Zn | 11.2 | ||||
Inverleigh (canola) | Grain yield (t/ha, 100 C drying) | N, P | 18 kg N/ha | 1.34b | 0.252 |
75 kg N/ha | 1.60a | 0.173 | |||
146 kg N/ha | 1.69a | ||||
0 kg P/ha | 1.38b | 0.196 | |||
25 kg P/ha | 1.69a | ||||
![]() | Biomass at grain harvest (t/ha) | N, P | 18 kg N/ha | 5.16b | 0.770 |
75 kg N/ha | 5.72ab | 0.527 | |||
146 kg N/ha | 6.02a | ||||
0 kg P/ha | 5.12b | 0.599 | |||
25 kg P/ha | 6.00a | ||||
![]() | Harvest Index | N, P (P = 0.07) | 18 kg N/ha | 0.279 | 0.0336 |
75 kg N/ha | 0.292 | 0.0199 | |||
146 kg N/ha | 0.293 | ||||
0 kg P/ha | 0.282 | 0.0218 | |||
25 kg P/ha | 0.294 |
![]() | Oil content (% oil at 6% moisture) | N, P | 18 kg N/ha | 46.04a | 0.529 |
75 kg N/ha | 43.49b | 0.362 | |||
146 kg N/ha | 42.63c | ||||
0 kg P/ha | 42.39b | 0.411 | |||
25 kg P/ha | 43.41a | ||||
![]() | Oil yield (t/ha) | N, P | 18 kg N/ha | 0.690b | 0.1248 |
75 kg N/ha | 0.777ab | 0.0853 | |||
146 kg N/ha | 0.806a | ||||
0 kg P/ha | 0.652b | 0.0970 | |||
25 kg P/ha | 0.818a | ||||
![]() | Protein content (%, 6% moisture) | N, P | 18 kg N/ha | 36.6c | 0.844 |
75 kg N/ha | 40.2b | 0.577 | |||
146 kg N/ha | 41.9a | ||||
0 kg P/ha | 42.2a | 0.656 | |||
25 kg P/ha | 40.5b | ||||
![]() | Protein yield (t/ha) | N, P | 18 kg N/ha | 0.282c | 0.0600 |
75 kg N/ha | 0.386b | 0.0241 | |||
146 kg N/ha | 0.431a | ||||
0 kg P/ha | 0.358b | 0.0467 | |||
25 kg P/ha | 0.412a |
Additional Resources
Crop Nutrient Decisions in HRZSize: 9.34 MB
Results Report from SFSSize: 0.61 MB