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The neoformation of the flower buds from the internodal segments of the flower stalk of Nicotiana tabacum L. var. wisc.38 cultivated in the glucose medium in the presence of light has been carried out. It is observed that the quantity of the absorbed glucose, as well as the increase of the dry weight was more in the light than in the dark, while the water content in the explants changes in the opposite direction. The absorption of glucose by the explants depends on the duration of light period and the light energy. Besides, the spectrum of light ranging between 598 and 644 nm was more effective on the absorption of glucose. The possibility of the intervention of light on the organogenesis by stimulation of the absorption of glucose is also discussed.
A sufficiently high light intensity can partially compensate the absence of glucose in the culture medium.
The presence of ATP in addition to high light energy, enhances the number of neoformated flower buds in the medium which is devoid of glucose.
The photosynthetic activity of the explants was relatively weak but not negligible in the first few days of the culture, but it increases during flower organogenesis.
The varistion of the chlorophylls content in each explant, particularly from fourth to twenty second days of culture, follows with the rate of photosynthetic intensity. It is therefore possible to conclude that the neoformation of flower buds was stimulated by increase of the photosynthetic intensity.