Hydrocarbon contained in leaf waxes of 30 species was isolated chromatographically. Branched and saturated hydrocarbons were found little in them. Most of hydrocarbon was confirmed to be n-alkane. Component of maximum content ofn-alkane and pattern of the component in each species are different expect the case thatn-nonacosane (C₂₉) contained 80% ofn-alkane of Cruciferae species. Pattern of the component ofCoix ma-yuenis similar to that ofC.lachryma-jobi.It is found that there are some plant species, which contain a good deal of even-numberedn-alkane.

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Young plants of several kinds of vegetables were grown in a plastic house, and changes of their growth parameters caused by shading with white cheeseclothes (about 70% of the solar radiation in the plastic house) were compared to clarify the difference of their shade tolerance.
1. Growth analysis were carried out 6 times on cucumber, eggplant, lettuce and radish in the first group, 29 times on cabbage and 27 times on mitsuba (Cryptotaenia japonicaHassk.) in the second group at various seasons. The average values of meteorological factors within the plastic house during the experimental periods were almost the same for all the vegetables except eggplant which had a little higher radiation and temperature.
2. In the first group NAR decreased 16%, LWR did not change, and SLA increased 6% by shading, so that RGR decreased 10%. In the second group NAR decreased 14%, LWR did not change, and SLA increased 5 % by shading, so that RGR decreased 10%. Increase of RLGR by shading occurred only in mitsuba (8%) . The changes of ULWR were almost the same as RGR in all the vegetables tested.
3. RGR of root was most depressed by shading compared with the other parts of plants, and there was a trend that the shading effect on RGR was stronger in leaf blades than in petioles in all the vegetables having petioles, except mitsuba in which there was no difference between them.
4. In cabbage and mitsuba of which growth parameters were analysed about thirty times, the shading effects on the growth parameters in the warm period and in the cold period were compared on the basis of the mean day temperature. The effects were all the same in the two periods.
5. The reaction of RLGR in mitsuba to shading was different from that of the other vegetables. RLGR of mitsuba increased clearly by shading. All the growth parameters except RLGR were affected by shading in the same way in all the vegetables. Therefore, the effects of shading given in a short period on the growth parameters seem to be the same in all the vagetables, but if the shading is prolonged, the effects might be different in mitsuba, one of shade plants growing natively in woodlands in Japan.

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An assimilation chamber whose inside temperature could be controlled was made to measure the photo-synthesis, respiration and transpiration of forest trees in situ. The switching power supply system was used in thermomodule circuit, which reduces the weight of the apparatus and make it easier to handle even in a primeval forest on steep mountain.
Deviation from the desired temperature during a 10-hour run was ±0.2°C under a constant thermal load (100 cal/min) . The settling time for the step input of temperature (28°C→23°C) was within 3 minutes and that of the load (100 cal/min→0 cal/min) was within half a minute.
The chamber was used to measure the photo-synthesis of intact sun leaves in a natural beech stand. The inside temperature closely followed the ambient air temperature with only a deviation of ±0.3°C during the day with fluctuating irradiations of sunlight.

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To develop a method for evaluating artificial light for plants, a mathematical model of transpiration rate in cucumber plants was presented by using parameters representing light, air temperature, humidity and spectral dependence of transpiration rate. The transpiration rate (E, mg⋅dm^-2⋅min^-1) was divided into two components ofE₁in darkness andE₂under radiation, as written byE=E₁+E₂. E₁was given byf₁ (T, H) , whereT (°C) andH (%) are air temperature and relative humidity, respectively.E₂was expressed asE₂=L⋅f₂ (T, H) , where L is the parameter representing the light condition and the plant response to the light. The wavelength region of 400 to 700 nm was divided into three regions of B (400≤λB≤500 nm), G (500≤λG≤600 nm) andR (600 <λR≤700 nm), correspond-ing to the spectral dependence of leaf conductance for water vapor in Cucurbita maximaL, and blue (b), green (g) and red (r) fluorescent lights were used for the examination; most of the spectral energy of those lights distributed inB, GandR, respectively. The light condition was evaluated by using the total light intensity (Q, nE⋅cm^-2⋅sec^-1) in the region of 400 to 700 nm and the relative light intensities ofI_B, I_G and I_R (I_B+I_G+I_R=1) inB, G andRfor representing the spectral energy distribution. The spectral dependence of transpiration rate was similar to that of leaf conductance and was represented by the parameters ofK_B, K_GandK_R (K_B+K_G+K_R=1) which characterized the transpiration rate affected by the respective lights inB, GandR. Thus, L was given byL=Q⋅ (K_B⋅I_B+K_G⋅I_G+K_R⋅I_R) , andf₂ (T, H) =E₂/Lwas determined by measuringE₂ under the respective light and air conditions. Therefore, E=f₁ (T, H) +Q⋅ (K_B⋅IB+K_G⋅I_G+K_R⋅I_R) ⋅f₂ (T, H) was presented as a model. From the fact that the transpiration rates simulated from the model were close to measured ones under two typical lights from white fluorescent and incandescent lamps at different air temperatures and humilities, it was demonstrated that the parameters representing the light can be used to evaluate artificial light for plants.

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