Abstract
Rapid acquisition of information about nitrogen (N) uptake and grain yield is an essential step in making site-specific in-season fertilizer N management decisions. The objective of this study was to quantify and validate the relationships between N uptake and grain yield of wheat using in-season measurements with atLeaf chlorophyll meter and GreenSeeker optical sensor at Feekes 6 growth stage (jointing stage) of wheat. The relationships were developed using data generated from experiments with multi-rate fertilizer N treatments and conducted in two consecutive wheat seasons (2017/2018 and 2018/2019) at two locations in the western Nile Delta of Egypt. A power function based on atLeaf measurement at Feekes 6 stage of wheat could explain 55.3% and 53.3% variations in the N uptake at this stage and grain yield at maturity, respectively. Measurements with GreenSeeker were related with N uptake and yield of wheat through exponential function and could explain 68.5% and 60.6% of the variation in N uptake and grain yield, respectively. The developed models were validated on an independent data set from another field experiment on wheat. The normalized root mean square error for the relation between atLeaf measurements and N uptake and grain yield were fair, whereas the fits were good for measurements with GreenSeeker. This study reveals that atLeaf chlorophyll meter and GreenSeeker optical sensor can be successfully used for establishing site-specific N management strategies in wheat.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by-nc-nd. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 7
Claim · model-written summary
AtLeaf measurements explained 55.3% of wheat nitrogen uptake variation.
- Taxon
- wheat
Triticum aestivume0 - Organ / stage
- Feekes 6 stagee0
- Outcome
- N uptakee0
- Value
- 55.3%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“A power function based on atLeaf measurement at Feekes 6 stage of wheat could explain 55.3% and 53.3% variations in the N uptake at this stage and grain yield at maturity, respectively”
Claim · model-written summary
AtLeaf measurements explained 53.3% of wheat grain yield variation.
- Taxon
- wheat
Triticum aestivume0 - Outcome
- grain yield at maturitye0
- Value
- 53.3%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“A power function based on atLeaf measurement at Feekes 6 stage of wheat could explain 55.3% and 53.3% variations in the N uptake at this stage and grain yield at maturity, respectively”
Claim · model-written summary
GreenSeeker measurements explained 68.5% of wheat nitrogen uptake variation.
- Taxon
- wheat
Triticum aestivume0 - Outcome
- N uptakee0
- Value
- 68.5%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Measurements with GreenSeeker were related with N uptake and yield of wheat through exponential function and could explain 68.5% and 60.6% of the variation in N uptake and grain yield, respectively”
Claim · model-written summary
GreenSeeker measurements explained 60.6% of wheat grain yield variation.
- Taxon
- wheat
Triticum aestivume0 - Outcome
- grain yielde0
- Value
- 60.6%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Measurements with GreenSeeker were related with N uptake and yield of wheat through exponential function and could explain 68.5% and 60.6% of the variation in N uptake and grain yield, respectively”
Claim · model-written summary
AtLeaf prediction fits for nitrogen uptake and grain yield were fair on independent wheat data.
- Taxon
- wheat
Triticum aestivumt0 - Outcome
- N uptake and grain yielde0
- Value
- faire0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“The normalized root mean square error for the relation between atLeaf measurements and N uptake and grain yield were fair”
t0“Wheat grain yield and nitrogen uptake prediction using atLeaf and GreenSeeker portable optical sensors at jointing growth stage”
Claim · model-written summary
GreenSeeker prediction fits for wheat nitrogen uptake and grain yield were good on independent data.
- Taxon
- wheat
Triticum aestivumt0 - Outcome
- fitse0
- Value
- goode0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“the fits were good for measurements with GreenSeeker”
t0“Wheat grain yield and nitrogen uptake prediction using atLeaf and GreenSeeker portable optical sensors at jointing growth stage”
Claim · model-written summary
The authors conclude both sensors can support site specific nitrogen management in wheat.
- Taxon
- wheat
Triticum aestivume0 - Outcome
- site-specific N management strategiese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“atLeaf chlorophyll meter and GreenSeeker optical sensor can be successfully used for establishing site-specific N management strategies in wheat”