This paper describes preliminary results on the build-up mechanism of physical quantities within a corn plant canopy. Small polyethylene covered net radiometers were constructed and used to measure the height distribution of net radiation. Miniature aspirated psychrometers were also constructed and used to collect data on the air temperature and water vapor pressure profiles within the canopy. Sample air from nine levels within the canopy was collected into beach balls using a pump system (see Fig. 3). CO₂ concentration in sample air was determined with an infra-red gas analyser. The energy balance approach was utilized to evaluate the fluxes of sensible heat, latent heat and carbon dioxide by layers within the canopy. The results so obtained are presented in Figs. 4, 5, 6 and 7.

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It is considered that there are three phases of decreasing yield in rice plant caused by strong wind; one is occurrence of atrophied kernels at a time before the heading, second is ill effect to fertilization and development of the grains at or near the heading time, and the last is shattering loss at later ripening stage. On the former two there are many reports by various authers (11, 6, 9, 10, 12 and etc.) but on the last little reports.
This investigation was made for clarifying the effect of different wind speed and that of stages after the heading and position of the grains on shattering in rice plant. Norin no. 29 cultured in pot were used in this experiment. Wind treatment were made in a wind tunnel in our institute. And following results were obtained.
1) When the plants were exposed to various wind velocity (6, 9, 12, 15, and 18 metre per second) for five hours at the full ripening stage after seven weeks from the heading, there was obtained no grain shattered in the treatment of 9m/s. or weaker wind speed, 0.3 percent of grain shattered at 12m/s., and the percentage increased quickly for increasing wind speed. On the other hand, breaking type lodging were also increased for increasing wind speed, and the shattered grains in lodged plants was less than that in non-lodged plants. Therefore, it seems the most shattering loss in rice plant occurs at the wind speed of about 15 metre per second.
2) From the treatment of 15m/s. of wind for five hours at different stages after the heading, the following result was abtained. Shattering grains was not occurred just at the heading stage, but it started at one week after the heading, and the maximum loss of shattering of about 40 percent was found in the treatment at four weeks after the heading. The present authors had supposed that the shattering would increase according the degree of ripening, but the result was not so. Although no accurate reasons can be found for this result, owing to the lack of any reliable data, it seems to have some relation with change of lodging resistance in rice plants.
3) The grains on upper part of the head were easiest to be shattered, and the reasons are due not only to wide vibration or severe fluttering of the upper part of the head but also weaker tensile strength or resistance to the shattering.
4) The results suggest some prevention methods against shattering loss causing by strong wind. Three of effective methods decreasing loss due to shattering will be: (1) construct windbreaks or hedges to decrease wind speed over rice fields: (2) make the strong resistance varieties by breeding and (3) break down the plants artificially in order to decrease the vibration of head just before the time of a typhoon attack. The last should be applied to only plants in full ripening stage.

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This paper presents data on the effects of winter weather on flowering and fruiting of Prunus mume.
The results obtained are as follows;
(1) Critical temperature for flower killing was -8.0°C--9.5°C, and air temperature near -4.5 °C--5.0°C was found to be critical for killing young fruits of Prunus mume.
(2) MIURA (1962) reported that the percentage of fruit set of Koume variety was high when the daily maximum temperature reaches more than 15°C.
(3) It would be desirable to cultre Prunus mume at the meteorologically suitable place where the minimum air temperature as low as -8.0°C--8.5°C in flowering stage and -4.5°C--5.0°C in the young fruits stage do not occur frequently, together with higher daily temperature in the flowering stage.

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(1) The estimation of heat balance for plant layers was carried out by using micro-meteorological data obtained on wheat field at night. The vertical distributions of the rate of cooling by long wave radiation, and of heating by eddy transfer of heat and dew formation in the plant layers are calculated. The results shown in Fig. 3.
(2) Amount of dew was measured by making use of sanitary cotton as the absorber of dew. The amount was compared with one calculated by heat balance method. From Fig. 5 it seems that dew in wheat field is formed predominantly by water vapour from the air layers above plant surface.
(3) Radiative cooling rates of air layers above this plant surface are calculated. Since the calculated cooling rates are larger than actual cooling rates, we can suppose that the air layers are warmed by eddy transfer of heat at night.

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