Explanation

LDP (Long Day Plant) These plants show flowering when they receive long photoperiod, above the critical photoperiod. $e.g.,$ henbane, wheat, oat, beet, spinach, raddish, lettuce, etc. SDP (Short Day Plant) These is plants show flowering when the photoperiod, or length below the critical period. Most of winter plants are SDP, e.g., potato, bean, tobacco, rice, sugar cane etc. DNP (Day Natural Plant) These plants can blossom thoughout the year. e.g., tomato, maize, cotton, pepper, etc.