Abstract:

The study was conducted to determine effects of nitrogen (N) supply levels on growth, flower yields and xanthophylls content of marigold, studying the cold marigold’s appropriate amount of nitrogen. This experiment was designed to find the affection of nitrogenous fertilizer on growth and development, flower production and production of lutein to Tagetese recta in cold region. Randomized method was used, in condition of fixed amount of potash and phosphate, to analyze the affection of 6 different levels of treatment on biological properties and yield of Tagetese recta. By increased amount of nitrogen fertilizer, delayed flowering, height, stem diameter, strains of crown diameter, number of branches, dry weight per plant and chlorophyll content were all show the same trend which increased in the first then decreased. In N3 condition, flower yield, lutein and yield were most, significant difference among treatments. In condition of this experiment, the reasonable amount of nitrogenous fertilizer to Tagetese recta in cold region was 90 kg/hm2, which can make flower yield reach to the most 24.11 t/hm2.