On germination of the Kintoki-carrot seeds. II

Abstract

In Japan, the Kintoki variety of carrot seeds are usually sown within forty five days after their harvest, without the removal of the pericarp or hairs. This results in very low germination. The following results were obtained from experiments performed in 1953 and 1954. (1) Not only the green, but the brown mature newly harvested seeds also generally increased the germination power and speed by storage in the laboratory. (2) In seeds of all stages of maturity, the germination was increased by the pericarp removal, soaking and drying (soaking in several hours and then air dried), and sun-drying treatments. (3) The extent of increasing the germination by the above treatments differed by the stage of mat-urity of the seeds. In the matured seeds, the differen-ces were very distinct, whereas, in the immature seeds they appeared but slight. (4) The effects of seed treatments on the germination decreased as time elapsed after the harvest. (5) Greater influence of these treatments upon germination was shown in immature seeds than matured, but the difference between them become smaller and smaller by the elapse of time after the harvest. (6) These treatments had greater influence upon the germination speed rather than on the germina-tion power. (7) The effect of sun-drying upon germination was influenced by the period of treatment. (8) The effect of soaking and drying on the germination was not directly proportional to the time or the hours of soaking; but it was found that about three to four hours of soaking seemed best. (9) Combination of treatments had greater effect on the germination than any single treatment. (10) The mechanism of improving germination by treatments must be very complex, and cannot be explained solely from the experiments performed.