チューリップ種子発芽におよぼす変温の影響

In the previous paper, the author reported that the optimum temperature for the germination of the tulip seeds is 5℃ and the beginning of the germination starts after 30 - 50 days long varying with the strain of seeds.
On the other hand, the alternation of temperature is influenced from this length till the beginning of the germination.
Judging from this phenomenon the author suggested that one of the obstacle in case of the tulip breeding by the seedling method is caused by the alternation of temperature in the germination term, and the shortening of the breeding-cycle is attained partially by the solution of the mechanism of the germination.
In the first experiment, the author recognized that the influence for the germination by a single round treatment of the alternation of temperature combined with the optimum temperature (5℃) and the higher temperature (20℃) was expressed by the prolongation of the basic length till the beginning of the germination (that basic length is obtained by the length till the biginning of the germination under 5℃), namely the integrating days under the optimum temperature till the beginning of the germination was affected badly in proportion to the length of the treatment of the higher temperature within the scope of alternation of temperature.
Then, in this paper the influence of successive treatment by the alternation of temperature was examined and the following facts were clarified.
1. The influence on a single round treatment of the alternation of temperature was intensified by the successive treatment.
2. The length till the beginning of the germination and the germination term were prolonged, and the germination energy fall off badly.
3. In case of the shorter length of the treatment of the optimum temperature within the scope of alternation of temperature, its influence for the germination was remarkable.
4. The activity on the ability of the germination was not checked, but coutrolled temporarily by the alternation of temperature. The ability of the germination recovered normally as soon as the treatment of the alternation of temperature was taken away.