ISSN:
1573-5036
Keywords:
Crop development
;
Grain yield
;
Nitrogen
;
Nitrogen dressing
;
Nitrogen economy
;
Nitrogen harvest-index
;
Soil Wheat
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Summary Nitrogen exerts its influence on crop growth and grain yield in various ways. Early top dressings or a high level of soil nitrogen stimulate tiller formation and leaf growth, which results in an increase of shoot dry weight and leaf area index. Late top dressings promote the survival of ear-bearing tillers, grain set and leaf area duration. Nitrogen compounds for grain growth are mainly supplied by the vegetative aerial parts (65–80%); the remainder originating from uptake and relocation by the roots after anthesis. The proportion of the total amount of nitrogen present in the grains, the nitrogen harvest-index, centers around 0.78 under optimum conditions. The recommendations for nitrogen dressing are based on the amount of residual soil nitrogen and on the requirement of the crop in the given environment. Both components may vary considerably due to environmental constraints. Despite inaccuracies in the assessment of mineral nitrogen content of the soil and the predicted nitrogen requirement of the crop, the recommendations for splitting nitrogen dressing in winter wheat have considerably improved the efficient use of nitrogen fertilizer.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02369972
