1. The pollen grains of four plants belonging to Gramineae were used in this experiment. 2 . When the selection of the sort of colloidal substance as medium, the adjustment of the thickness of the medium layer and the humidity in a moist chamber were suitable, pollen grains germinated well. 3. The humidity in the moist chamber (petri dish of 9 cm in diameter and 1.8 cm in height) was regulated by one, half or a quarter sheet of the filter paper (11 cm in diameter) contained 1 cc water. 4. Colloidal substance used as medium was selected from "yellow, gray, Ishizu and Miyagi" gelatin. 5. The pollen grain of Hordeum vulgare L. "Hadakashinriki " germinated best on the 15 At thick medium of 5 % yellow gelatin contained 5 % sucrose in the moist chamber by a quarter sheet of a filter paper at 25℃. 6. The pollen grain of Oryza saliva L. "Norin No. 18 " g erminated best on the 15 At thick medium of 4 % gray gelatin contained 10 % sucrose in the moist chamber by a half sheet of a filter paper at 25℃. 7. The pollen grain of Panicum crusgalli L. " Loca l variety " germinated best on the 15 a thick medium 3 % yellow gelatin contained 30 % sucrose in the moist chamber by a quarter sheet of a filter paper at 21℃. 8. The pollen grain of Zea Mays L. " Local variety " germinated best on the 20 At thick medium 25'-30 % yellow gelatin contained 5-40 % sucrose in the moist chamber by a quarter sheet of a filter paper at 28℃. 9. The best germination ratio shown in each polle n grain is as follows. Hordeum vulgare L. " Hadakashinriki " 99.7 % Oryza sativa L. " Norin No. 18 " 99.2 % Panicum crusgalli L. " Local variety " 98.6 % Zea Mays L. " Local variety "100 % 10. The more hypertonic the medium was, that is, the slower the water absorption of pollen grains was, the more the pollen grains expanded. 11. The pollen grains expanded rapidly on a medium layer, and after some rest time, they began to germinate. The pollen grains which expanded a little germinated in high percentages rather than ones expanded much. 12. The plasma in the pollen grain change to the sol state from the outside of it by sucking the water rapidly. Then, if the amount of sucked water is suitable the pollen grain can germinate. But, if it is over the swelling pressure in the pollen grain become over too, and the pollen grain plasmoptyses. On the other hand, if suction speed is too slow the plasma can not change to the sol state. On that occacion, it swells and the pollen grain plasmoptyse in continuing such a suction speed. 13. The humidity by a half or a quarter sheet of a filter paper (11 cm in diameter) in the moist chamber is equivalent to it by about 0.02 mol NaC1 solution.
Mendeley出力
