Plants with long sunshine time include winter wheat, barley, rape and radish. Long-day plants refer to plants whose sunshine length exceeds the critical day length (14- 17 hours) or whose dark period must be shorter than a certain number of hours to form flower buds. Otherwise, flower buds can't be formed, and they can only stay in the vegetative growth stage.
Short-day plants include soybeans, corn, rice and viola yedoensis. Short-day plants refer to plants that can bloom only when the sunshine length is shorter than its critical day length (less than 12 hours, but not less than 8 hours). In a certain range, the longer the dark period, the earlier it blooms. If it is under long sunshine, it will only grow nutritionally without flowering.
Extended data
The flowering of long-day plants and short-day plants is not directly related to the duration of sunshine, but the duration of darkness will directly determine whether they bloom or not. If you want to promote the flowering of daytime plants, you don't need to extend the sunshine duration.
As long as the light is given in the continuous darkness for a short time, the continuous darkness can be shortened below a certain critical value, and the continuous darkness can only be extended to short-day plants.
The critical day length (night length) of long-day plants and short-day plants varies from species to species, and is not strictly 12 hour. The critical day length of long-day plants is often shorter than 12h, while that of short-day plants is longer than 12h, so we must distinguish short-day plants from long-day plants according to the definition, not the length of critical day length.
Baidu Encyclopedia-Longyangguang Plants
Baidu encyclopedia-short-day plants