One set of the plant was grown at 12 hours day and 12 hours night period cycles, and it flowered while in the other set night phase was interrupted by flash of light, and it did not produce flower. Under which one of the following categories will you place this plant?

Explanation

(d) : Plants require a day length or light period for flowering, this light period is called as photoperiod. It was first studied by Garner and Allard (1920). Short day plants (SDP's) flower in photoperiods less than critical day length, e.g., Nicotiana tabacum, Glycine max (Soybean), Xanthium strumarium. Further, these plants require long uninterrupted dark period and hence are called long night plants. Long day plants (LDP's) flower in photoperiod more than critical day length, e.g., Hyocyamus niger (Henbane), radish, Beta, spinach, Plantago, etc. Day neutral plants flower in any photoperiod, e.g., tomato, maize, cucumber, etc.