The germination of strawberry (Fragaria grandiflora EHRH.) seeds was studied. All 13 varieties tested showed a strong photosensitivity in their seed germination, that is, the germination was much inhibited in the dark. Alternating temperatures of 15° and 30°C much stimulated germination in both light and dark. Among constant temperatures of 15°, 20°, 25° and 30°C, 25°C was the best for germination, followed by 30°C and 20°C, and the low temperature of 15°C was the worst. This indicates that the relatively wide range of constant temperatures between 20°C and 30°C are adequatee to .their.r germination.In about 10 months after harvest, no diminution of dormancy was shown in strawberry seed.Among chemicals tested for stimulating germination, potassium nitrate was the most effective at concentrations of 0.1 and 0.2%. Ethrel and gibberellin were also effective, but their effectivenesses were not so large as potassium nitrate.Thiourea was only slightly effective at much lower concentration of 0.05%. Low temperature treatment was ineffective in the short period of 10 days, but effective in the relatively long period of one month or more, and the longer the treatment period, the larger the stimulative= effect. Scarification of seed coats with concentrated sulphuric acid for two to three minutes was rather effective for stimulation in both light and dark. This indicates that the cause of dormancy of strawberry seeds lies mainly in thei fruit and seed-coat, not in the embryo.Far-red light showed very strong inhibition on the strawberry seed germination . This inhibition was not recovered even by alternating temperatures, but overcome to some extent by low temperature treatment.In this experiment, strawberry seeds were stored well in dry condition of room temperature, or in either dry or open condition at 5°C.

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