الفهرس 
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Abstract
Two separate experiments were carried out at Al-Jabal Al-Akhdar region, Libya during six consecutive years and at Kafr El-Sheikh, Egypt during two consecutive years for two times. The first experiment aimed to investigate the seed germination and some vegetative growth traits of Cyclamen rohlfsianum under the native habitat, in addition, measure the annual increments of leaves and tuber size in seedling of Cyclamen rohlfsianum in their native habitat, over 6-year growing period, to determine the period from sowing to flowering. While, the second experiment aimed to investigate the effect of NPK fertilization at the different levels (0.0, 0.5, 1.0 and 1.5 g kristalon (19: 19: 19) /pot 15cm in diameter) on growth, flowering, tuber productivity and chemical constituent under cultivation. The obtained results could be summarized as follows:
First experiment:
Seeds showed high germination percentage (88±4%), followed by a rapid development of the fat hypocotyl during 29-35 days of growth and the lastly, one leafy cotyledon emerged from the seed coat. The tuber fresh weight and diameter varied with the age of the plants, depending on the leaf number and area. These slowly increased for the first three years, then at a more rapid rate for the following two years with the highest reached at six years. Flowering did not occur until number of leaves and total leaf area were at least 3 and 49 cm2, respectively. The vegetative tuber size of 6.15 g fresh weight and 2.8 cm diameter, (4-year-old plants) were probably large enough to produce, in the next year (5th year of growing period), three or more flowers (3.5±0.9) and thereafter, more than three leaves emerged (3.76) whereas, 79±3.5% of plants flowered. However, flowering tuber size sharply increased to 21.27g and 5.49cm, respectively for 6-year-old plants, which were associated with increases in flowering percentage (98±7%), number of flowers (4.3±0.4) and total leaf area (111.78 cm2).
Second experiment:
All fertilization levels had no significant effect on time of flowering, number of flowers per plan and pedicel length, in the year one of the both experiments. While, in the year two of the both experiments, all fertilization levels were significantly advanced the time of flowering. Flowering was advanced 7 days by medium and high levels and 6 days by low level. Fertilization treatments at the high and medium levels gave the highest number of flowers per plant and tallest pedicel.
Leaf number, leaf area, petiole length, diameter and fresh weight of tuber were significantly affected by fertilizer rate in both year of the both experiments. However, fertilizer at high and medium levels were the most effective treatment with non-significant differences among themselves, it produced the highest increase in leaf number and leaf area, longest petiole, diameter of tuber and the heaviest fresh weight of tuber.
Chlorophyll a and b (mg/g fresh weight) and leaf and tuber N, P and K contents (in %) significantly increased with increasing levels of NPK fertilization, with non-significant difference among high and medium levels.
The nitrogen, phosphor and potassium contents (in %) in the tuber of high fertilizer plant were in the range 1.45-1.67; 0.26-0.29 and 2.95-3.00% respectively, of dry matter at harvest, while N, P and K contents (in %) of the leaf were in the range 2.91-3.10, 0.31-0.40 and 3.92-3.97%, respectively.
It is obvious from the aforementioned data that, there was no difference between medium and high fertilizer levels. Thus NPK application can be reduced without affecting all traits.