Optimum conditions for germination and storage of Duboisia myoporoides R. BR. seeds were studied in 1970 and 1971.
1) Weight of the seed used here was 1.4±0.06mg and 1.2±0.02mg in 1970 and 1971, respectively. 2) At constant temperatures little or no germination was observed; only 2% of germination was seen at 30°C, and at the other constant temperatures of 10, 20, and 40°C seeds did not germinate at all.
3) Seeds exposed to a low temperature of 10°C for the period of 5 to 25 days failed to germinate entirely.
4) Diurnal alternation of temperature was found to promote seed germination. The best results were obtained in the combination of 15°C (5 hr) and 30°C (19 hr), and in the case of 10 and 30°C, the most suitable time for these temperatures was 16 and 8 hours, respectively.
5) Gibberellin treatment gave the same effect as alternating temperature on germination, and still more promote it. Optimum concentration of gibberellin was 100 to 200 ppm, and treating time with these concentration was 48 and 24 hours, respectively.
6) The effect of light on germination was not recognized.
7) As to the storage of seeds, it was noted that moisture condition during the storage influenced more than did temperature condition; seeds stored under dry condition kept higher germination capacity for about 4 months.

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Using the seeds ofEragrostis abyssinica SCHRAD., which had been harvested on September 9, 1970, and stored at the room, 5°C and -17°C storing conditions, germination behaviours, including days from sowing to germination, germination process, germination duration, final germination percentage, transition of germination pattern during the storage, were studied during the term from October, 1970, to December, 1971, repeatedly 15 times with a month intervals.
At the starting test period, germination started 1 day after sowing and continued during the 43 days, and germinated 80% of whole seeds used at the final date. Seed dormancy was not remarkably recognized. In the following germination test, it was ascertained that the earlier was the germination test, in other words, the shorter was the storage period, the longer was the germination duration. Final germination percentages once decreased, and afterwards they increased again at all the storing conditions. The lower was the storing temperature, the earlier was these decreasing and increasing pattern. The lower was the storing temperature, the smaller was the variation.
After 11 months storage, germination percentages of seeds stored at the room condition drastically decreased, but germination percentages of seed stored at the -17°C condition were kept at more than 80% even after 15 months storage. The decreasing process of final germination percentage of the seeds stored at the 5°C storing condition may be regarded as belonging to the middle phenomenon between them.

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Leaf blades, petioles and stems of 8 healthy and 10 witches' broom diseased sweet potato plants were analyzed for 13 elements including N, P, K, Ca, Mg, Fe, Mn, Zn, B, Mo, Cu, Na and Al. The concentrations of N, K, B and Cu in the leaf blade, of K, Ca, Mo and Cu in the petiole, and of N and Mg in the stem of healthy sweet potato plants were significantly higher than those of witches' broom diseased ones.
Among the three plant parts, the N and Mn concentrations of the leaf blade were significantly higher than those of the other two plant parts in both healthy and witches' broom diseased sweet potato. There was not significant difference in the Zn concentration among the leaf blade, petiole and stem of both healthy and witches' broom diseased plants. The other 10 elements showed different tendencies of distribution between healthy and witches' broom diseased plants.
Relationships of element concentrations were studied between the leaf blade, petiole and stem of sweet potato plants. The concentrations of K, Ca, Zn, Fe, Mn and Na were significantly correlated between the leaf blade and petiole, between the leaf blade and stem, and between the petiole and stem in both healthy and witches' broom diseased plants. In general, more elements were correlated between the potiole and stem than those between other plant parts in both healthy and witches' broom diseased plants.
Possibilities of using plant analysis were discussed in order to diagnose witches' broom disease infection of sweet potato plants.

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The influences of temperatures and gaseous conditions on dormancy and germination in rice seeds were investigated, in order to make clear the mechanism of seed dormancy.
1. In comparison of seed dormancy found in indica type and japonica type varieties, the number of varieties of indica type showing a high seed dormancy were more remarkable than that of japonica type.
2. The speed of activation of seed germination in non-dormant varieties was faster than that in dormant ones. This activation mentioned above seems to be related to germination percentage and magnification of temperature-extent, in which seeds of rice could germinate. Then, the activation of seed germination was recognized as showing varietal difference, but seed germination activated entirely was not recognized the varietal difference at 20°C-32°C.
3. Effects of alternating treatments of temperatures on the breaking dormancy of seeds were only recognized on plot alternated between 20°C and 32°C. High temperature treatment of seeds at 40°C immediately after sowing broke completely the seed dormancy, therefore it was considered that effect of high temperature treatment on the breaking of seed dormancy was not revealed by dryness of seeds, but was directly revealed by action of high temperature.
4. On the germination of dormant seeds, dormancy of fully ripened seeds was completely broken when seeds were placed in 100% oxgen tension, and the acceleration of germination percentage could be taken in high oxgen tension. Accordingly, it became clear that oxgen supply was requested on the germination of dormant seeds.

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