植物的春化作用意指植物需要經過曝露於冬季的低溫後才能在隨後的春季中開花,而存在於植物、動物乃至於真菌類生物的光週期現象,則泰半相關於發育反應。透過春化作用,自然界中的植物即可在漸暖且較合適的春天裡進入生殖生長期,進行果實或種子的生產來完成一世代循環。而光週期的形成與光週期反應亦為生物長期演化的結果,藉由日長變化作為發育階段歷程演進的適當指標,使得生物能夠持續往前生長與發育,歷經生活史的各個發育階段終至於完成一個世代。發光二極體(LED)可以作為大自然中太陽光的替代光源,從農作栽培的觀點確實在縮短生育期、調節生產期、提高產量或提升品質等方面具有可行性,值得投入探討及系統研發。
The vernalization requirement has been found existed in plants through which plants acquire the competence to flower in the spring after experiencing a period of low temperature in winter. Photoperiodism (or photoperiodicity) occurs in plants, animals and even fungi, and is the physiological reaction for these organisms to changes of daylength, mostly the developmental responses. Plants may initiate or accelerate the flowering process after the vernalization and then produce seeds in better environmental conditions to complete their life cycle. The response to photoperiod has evolved because daylength is a reliable indicator of the time of the year that enables developmental events proceeding as scheduled to fulfill a generation. The lightemitting diode (LED) can be used as a substitute of solar radiation under structure or in field, providing radiation and energy for the growth, development and reproduction of a plant. Many studies have proved the feasibility and applicability of using LED to shorten growth duration, adjust production timing, increase yield and promote quality of harvested products. With such a multifunctional application advantages, researches on establishing systems incorporating LED as a light source are greatly encouraged. Photoperiodism;Vernalization;Lightemitting