Location: Hard Winter Wheat Genetics ResearchTitle: Evaluating canopy spectral reflectance vegetation indices to estimate nitrogen use traits in hard winter wheat Author
|Frels, Katherine - University Of Minnesota|
|Joyce, Brian - Hitachi, Inc|
|Baenziger, P. Steven - University Of Nebraska|
Submitted to: Field Crops Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/4/2017
Publication Date: 12/19/2017
Citation: Frels, K., Guttieri, M.J., Joyce, B., Baenziger, P. 2017. Evaluating canopy spectral reflectance vegetation indices to estimate nitrogen use traits in hard winter wheat. Field Crops Research. 217 (2018) 82-92. https://doi.org/10.1016/j.fcr.2017.12.004.
DOI: https://doi.org/10.1016/j.fcr.2017.12.004 Interpretive Summary: Winter wheat plants that efficiently take up nitrogen from the soil and convert it to protein are desirable because they make the best use of applied fertilizer, which generally is a costly production input. Efficient nitrogen use can lead to higher protein grain, higher yield, and less fertilizer leaching or run-off. Unfortunately, measuring nitrogen use efficiency is very labor intensive, requiring multiple samplings of plant tissue, grinding tissue, and measurement of weight and nitrogen concentration. The goal of this research was to use measurement of light reflected back from the wheat plants after flowering and until maturity to predict nitrogen use efficiency. This research evaluated 28 different approaches for analyzing the light to identify the most effective methods. Five analytical methods most consistently predicted nitrogen use efficiency characteristics in two years of the field trial, the Boochs2, DDI, Maccioni, MCARI2/OSAVI2, and the TCARI/OSAVI spectral indices. Among these, the Maccioni index was most strongly associated with nitrogen use efficiency characteristics in two years of field trials. Our results provide wheat breeding programs with a cost-effective analytical tool for predicting nitrogen use efficiency in their routine testing programs.
Technical Abstract: Wheat nitrogen use efficiency must be improved to reduce the need for nitrogen (N) fertilizers. This study was conducted to determine if measurement of canopy spectral reflectance (CSR) could be used to non-destructively and indirectly select wheat genotypes with improved nitrogen use traits. Canopy spectral reflectance measurements were collected during grain fill in a 299-genotype trial planted near Ithaca, NE in 2012 and 2013, and 28 vegetation indices were calculated from the data. The relationship between vegetation indices (VI) and nitrogen use (NU) traits was investigated. Vegetation indices were highly heritable in both years and predicted the NU traits anthesis biomass, mature biomass, grain N yield, grain yield, N harvest index, N utilization efficiency, N uptake efficiency and post anthesis N uptake. One VI, Maccioni, performed most consistently and was significantly related to several nitrogen use traits. The results of this study indicate that VIs, in particular the Maccioni index, could be used in wheat breeding programs to non-destructively phenotype for nitrogen use traits.