In the previous report the author classified the sesame varieties based upon their photoperiodic responses into five groups, viz., 1) a group highly sensitive to both short-day and long-day conditions, 2) a group more sensitive to short-day, while less to long-day conditions, 3) a group less sensitive to short-day, but more to long-day conditions, 4) a group low sensitive to both long-day and short-day conditions, 5) a group sensitive to long-day conditions only. The present paper gives the results of tests carried on at the Shikoku Agricultural Experiment Station, Zentsuji, in 1955. The latitude of this place is 34°13′N. Different days were used in the growing of 30 sesame varieties obtained from eight countries, where the following daily periods were maintained from July 10 to August 10 : a) 8 hours per day, b) natural conditions, and c) in the day time, by natural exposure, at night illuminated all night with two bulbs of 100w. from the distance of 1.5M. These were sown on June 30 and after treatment their growth was put to their natural conditions. The effect of the photoperiodic responses on the growth of sesame varieties belonging to the above five groups and the results of the experiments are summarized as follows : 1) The varieties of sesame which were introduced from Africa, Indonesia and a part of India did not ripen fully by the long-day management, which hindered to procure ripened capsules. 2) The color of corolla showed some change by the long-day managemen ; and as far as the varieties of high sensitivity to both long-day and short-day are concerned, the color of the flowers was recognized to have a tendency to change from light to dark. It is presumed that temperature has a close bearing as is inferred that by the long-day management it bloomed in the low temperature of October. 3) The shapes of the leaf blade are variable in general ; in the best time of growth, among the varieties which have a compound was or palmete simple type of leaf, under the long-day management, the degree of lobation in a leaf was remarkable ; under the short-day management, on the contrary, lobation was less found. 4) With regard to the leaf type, as a general rule, most of the group which is highly sensitive to both short-day and long-day conditions, in the period of vegetative growth, a fusses the ternate compound leaf ; while the groups of low sensitivity to both long-day and short-day conditions, of long-day conditions of low sensitivity to short-day, while low to long-day conditions were generally of simple leaf type. 5) The number of flowers per axil also changes : under favorable nutrition the number of flowers per axil was peculiar to the variety, and under unfavorable environment a decrease wasvaried. According to the short-day management the decrease of number of flowers per axil was recognized in general. 6) The short-day management capsule growed short and small ; the number of seeds per capsule diminished, and the seed, both in its shape and size showed some variation.
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