Claim · model-written summary
P area had R = –0.40 at low canopy positions and was unsuitable as a replacement shading indicator.
- Taxon
- Macadamia integrifolia
Macadamia integrifoliae1 - Outcome
- R valuese0
- Value
- –0.40e0
- Qualifier
- low canopy positionse0
- Comparator
- percentage ground covere0
Not reportedMaterialGeneCompoundOrgan / stageInteractorInteractor roleSecond interactorSecond interactor roleTreatmentSettingDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Nitrogen area and P area gave the highest R values (–0.60 and –0.40 at low canopy positions), and neither was a suitable replacement for percentage ground cover as a leaf-based shading indicator.”
e1“Macadamia integrifolia”
Title
D. O. Huett; B. J. Gogel; N. M. Meyers; et al. Australian Journal of Agricultural Research 2001. doi:10.1071/ar00066
Other claims from this paper (19)
- Association At Alstonville, leaf N%, P% and specific leaf weight increased significantly with PFD.
- Association At Alstonville, leaf N amount per area and P area increased significantly with PFD.
- Method / resource Regression analyses gave a maximum R squared of 0.59.
- Association HOL had higher N%, N area and SLW than FEL and YTL, which were equal.
- Association YTL and FEL had equal P% and P area, both exceeding HOL.
- Association Cultivar did not significantly affect N%, N area or SLW.
- Association Cultivar 660 exceeded 781 and 344 in P% and P area.
- Association Cultivar 781 exceeded 344 in P% and P area.
- Association At district sites, leaf parameters increased significantly with PFD.
- Association Leaf parameters correlated weakly negatively with ground cover; the correlation declined with height and PFD.
- Method / resource N area had R = –0.60 at low canopy positions and was unsuitable as a replacement shading indicator.
- Method / resource The N-area regression coefficient best correlated with ground cover (R squared 0.55) and may be useful as a shading indicator.
- Observation At position 1, HOL N concentration ranged from 1.3% to 1.8%.
- Observation At position 1, HOL P concentration ranged from 0.06% to 0.11%.
- Association N parameters were very poorly correlated with kernel yield at all five tree positions.
- Association HOL P parameters correlated weakly negatively with kernel yield at positions 1 and 2.
- Recommendation The study did not support recommendations to reduce leaf N because of detrimental yield effects.
- Recommendation Diagnostic leaf sampling should be modified to avoid shading reductions in N and P and cultivar effects on P.
- Method / resource Current diagnostic leaf N and P standards cannot reliably diagnose macadamia orchard nutritional status.