Observation of the phenomenon of plant light cycle

related topicsFirst, the principlemany
plants
need to go through a certain period of light (photoperiod) to flower. And the leaf is known to be the organ that feels the effects of the light cycle. Under certain light cycle conditions, certain special metabolites are formed in the leaves and passed to the growth point, resulting in the formation of buds at long points. Under the condition of natural light, plants are artificially given short daylight, intermittent day, intermittent night and so on to understand the alternating day and night light and darkness and its length on the strong flowering of her ears, soybeans, rice and other short-day crops.II. Materials and equipment: 1. Soybean seedlings or heron seedlings;
2. Black cover (white outside) or dark box;
3. dark cabinets or darkrooms;
4. Daylights or red light bulbs (60 to 100 watts);
5. Automatic control of light source time switches.3, experimental steps when soybean seedlings grow the first leaf, or heron seedlings grow 5 to 6 leaves (night temperature in 18 to 20 degrees C or more), that is, the following method to give different treatment, in general, continuous processing of 10d can be completed. Processing light cycle flowering / not flowering short daylight daily light 8h (8 a.m. to 4 p.m.) intermittent day every day 11.5h to 2.5h into the dark (or with a black cloth) intermittent day 3h intermittent night on the basis of short daylight treatment, 12h to 1h a.m. light 1h at night, with intermittent night control of natural light conditions.