NITROGEN FERTILIZATION OPTIMIZATION ALGORITHM BASED ON IN-SEASON ESTIMATES OF YIELD AND PLANT NITROGEN UPTAKE

Autor:	Ronald L. Elliott, E. V. Lukina, A. R. Klatt, Marvin L. Stone, K. W. Freeman, R. W. Mullen, Gordon V. Johnson, William R. Raun, John B. Solie, Wade Everett Thomason, K. J. Wynn
Rok vydání:	2001
Předmět:	Daytime Physiology food and beverages Sowing chemistry.chemical_element engineering.material Nitrogen Normalized Difference Vegetation Index Nitrogen fertilizer Human fertilization Agronomy chemistry Yield (wine) Botany engineering Environmental science Fertilizer Agronomy and Crop Science
Zdroj:	Journal of Plant Nutrition. 24:885-898
ISSN:	1532-4087 0190-4167
Popis:	Current methods of determining nitrogen (N) fertilization rates in winter wheat (Triticum aestivum L.) are based on farmer projected yield goals and fixed N removal rates per unit of grain produced. This work reports on an alternative method of determining fertilizer N rates using estimates of early-season plant N uptake and potential yield determined from in-season spectral measurements collected between January and April. Reflectance measurements under daytime lighting in the red and near infrared regions of the spectra were used to compute the normalized difference vegetation index (NDVI). Using a modified daytime lighting reflectance sensor, early-season plant N uptake between Feekes physiological growth stages 4 (leaf sheaths lengthen) through 6 (first node of stem visible) was found to be highly correlated with NDVI. Further analyses showed that dividing the NDVI sensor measurements between Feekes growth stages 4 and 6, by the days from planting to sensing date was highly correlated with final grain...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::b1c3895de36be8b00166be2ef0bcb9e8 https://doi.org/10.1081/pln-100103780 Zobrazit plný text záznamu