1970 年 83 巻 986 号 p. 281-284
Effects of temperature and growth regulating substances on flowering of Pharbitis nil (strain Violet) were studied under long day conditions of 16 hours light.
1. Plants grown at 22° and treated with N-3-chlorophenyl-N'-phenylurea (CP) and N-3-nitrophenyl-N'-phenylurea (NP) ** in 1mg/l developed flower buds on the main stem in 33.3 and 46.6% plants respectively, while control plants produced a few flower buds only on axillary stems.
2. Plants grown at 27° and 5° for 15 and 9 hours respectively under 16 hours light produced flower buds on the main stem in all the plants. Exposure to low temperature (5°) was given during the first part of the light period. Treatment with gibberellic acid (GA3) in 100mg/l produced flower buds at lower nodes than the control plants. Abscisic acid (ABA) and Indoleacetic acid (IAA) showed similar but less effect.
3. When grown at a temperature of 27° (15 hours) and 17° (9 hours) under 16 hours light, treatment with CP, NP, GA3, IAA, ABA and kinetin (K) did not produce flower bud on the main stem but produced some flower buds on axillary stems. Maximum percentage of plants setting flower buds were recorded by treatment with CP in 10mg/l.