Abstract
The crossing technique of common beans was studied, using a dwarf variety Masterpiee.
(1) When a flower is castrated on the day before flowering, there is a danger of breaking anthers during the operation and following self fertilization and moreover it becomes difficult to work because the pistil grows to curve spirally.
(2) On the contrary, if the castration is done at the four or five days before flowering, it is difficult to operate because of the very small size of bud and there is a danger of injuring the pistil.
(3) The most favourable time of castration, therfore, seems to be about 3 days before flowering.
(4) It appears to be preferable to pollinate within 24 hours after the castration, in the morning if possible.
