Models of growth and development of wheat triticum aestivum cultivar gabo in relation to plant nitrogen
Angus, J.F.; Moncur, M.W.
Australian Journal of Agricultural Research 36(4): 537-544
ISSN/ISBN: 0004-9409 Accession: 005910143
Wheat plants were grown in culture solutions differing in N concentration and transferred between the solutions at the time of floral initiation. Rates of growth and development were expressed in relation to the N concentrations of the whole plants. Growth rate increased and developmental rate decreased with increased plant N concentration, the extent depending on the developmental stage when the N was supplied, the duration of supply, and the concentration of N in the solution. Simple dynamic models fitted to the data accounted for 97% of the variation in observed biomass and 93% of the variation in rate of development. The models are based on a concept of relative N concentration, an expression of the actual N concentration of the plant in relation to the maximum and minimum possible N concentrations at a particular developmental stage. The models suggest possibilities for calculating the growth response to N fertilizer applied at any time during the development of a crop.