Influence of nitrogen fertilizing on weed infestation in sugar beets
1994
Braeutigam, H. (Goettingen Univ. (Germany). Inst. fuer Zuckerruebenforschung) | Schaeufele, W.R.
A two year field experiment was conducted near Goettingen to study the influence of N fertilizing on weed infestations as well as development, yield and quality of sugar beets. The weed infestation was modified by chemical weed control methods. The analyses for the amount of nitrate(min) in the soil was replicated two times. The results showed, that at all dates of assessment the leaf area of beets increased with higher levels of N fertilizing (0, 40, 140, 240 kg/ha). Simultaneously, the leaf area of weeds increased until the rows were covered by beets and then decreased until the harvest date. There were no significant differences between leaf areas of weeds determined at various observation dates. Increasing the amount of N fertilization resulted in an increase of beet yield, dry matter of beet and leave, nitrate content and nitrate extraction of beet, leave as well as weed and nitrate(min)-content; at the same time a decrease in white sugar yield was observed. The weed infestation influenced all yield parameters negatively. As weed infestation increased the sugar content decreased slightly, while the amount of the total nitrate (according to the method of Kjeldahl) in beet and leave remained stable
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