The influence of nitrogen fertilizations and light intersity on mother plants productivity and the rooting of cuttings of Chrysanthemum (cultivar - Horim Golden)

Mother plants of Chrysanthemum cv. "Horim Golden" have been cultivated at three levels of nitrogen fertilization, dosage for a 3 l pot was 100,500,1000 mg N. The plants were growing with fluorescent lamps on (5000 lx or 10000 lx). The rooting of the cuttings obtained under such conditions took place with 5000 lx. The effect of nitrogen on the productivity of mother plants depended on the light intensity. Higher nitrogen doses affected favourably the number of cuttings, the growth and number of roots per cuttings - only when higher light intensity was applied for mother plants. Light of various intensity used in the cultivation of chrysanthemum mother plants had a significantly higher effect on the dynamics of rooting that did nitrogen fertilization. High intensity light, irrespective of the nitrogen dose used, also increased the weight and number of roots per cutting. Moreover, a clear correlation has been found between the carbohydrate content in cuttings and the dynamics of rooting and the number and weight of roots formed. The process of root formation took place later and was slower in cuttings in which a higher carbohydrate content was found; however, the number and weight of roots formed by these cuttings were considerably higher. In cuttings characterised by a low carbohydrate; total nitrogen ratio a decrease in the number and weight of roots has been found