Fluctuations in the leaf numbers inPaphiopedilum insignePfitz. var, sanderae Reichenb. fil, were examined under controlled environments. Plants were cultivated for 18 months in high, medium, and low temperature rooms of a natural light phytotron and under a usual condition for growingPaphiopedilum. Stems of this species lived for more than 40 months from emergence to death. The fluctuation of the leaf number through one life cycle of a stem was estimated from the compiled data. High temperature promoted an increase in leaf number and low temperature inhibited it. Leaf shedding was concentrated in the autumn and winter in all treatments and was assumed to occur two or three times in the life cycle of a stem. This multiphased leaf-shedding nature is discussed here.

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When large quantities of farmyard manure (FYM) are applied excess salts may become a serious problem, since green-house soil is not exposed to natural leaching by rainwater. In a soil applied excess FYM, the major cations that contribute to excess salt accumulation are potassium and calcium. The areas of two green-house were 71.5 m²respectively. Each house had two plots, one of which was applied at the rate of 50 t, and the other was 5t FYM per 10 a. There were three rows in each plot. Leaching water was introduced into a tank (100l) out side the house through the vinyl sheets placed at the bottoms of the rows. Results were as follows:
1) There was no remarkable difference between the standing crops and fruit yield of the 50 t FYM plot and those of the 5 t FYM plot.
2) The pH value for the soil of 50 t FYM plot was consistently higher than that of 5 t FYM plot. It was 8.0 consistently for 24 weeks after planting and then lowered to 7.0. In the soil received 5 t FYM, soil pH was consisted about 7.0 by 16 weeks after planting and then lowered to about 5.0. Initial high conductivity value (3.0 mmho) due to FYM application decreased rapidly to 2.0 mmho after 16 weeks of planting in soils received 50 t FYM.
3) Most of the salts in FYM are soluble. In soils received 50 t FYM, potassium extracted by N-ammonium acetate (exchangeable) was measured to 25 me per 100 g soil in initial growing stage. The value measured was the sum of exchangeable and watersoluble potassium. The high concentration of exchangeable potassium in initial stage decreased rapidly to 10 me after 16 weeks of planting and gradually to 5 me after 32 weeks of planting. The decrease of potassium concentration in the soils was due to uptake by tomato plants and leaching.
4) High concentration of calcium extracted by N-ammonium acetate was observed in the soils received 50 t FYM. It seemed to be derived from exchangeable calcium, water soluble calcium, and some other compounds such as calcium carbonate dissolved by N-ammonium acetate.
5) In general, soils received excess FYM accumulates a large quantity of salts. However, excess salts were not accumulated in this green-house cultivation because of drainage system lain vinyle sheets at the bottoms of the rows. Draining water probably promoted the leaking of salts. Consequently, damages by excess salts for tomato crop were not observed in this experiment.

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Effect of excess farmyard manure (FYM) on tomato plant was studied under green-house conditions. There were two plots one of which was applied at the rate of 50t FYM per 10 a and the other was applied at the rate of 5t FYM per 10 a. The FYM used in this study contained 2.8% nitrogen, 2.8% potassium and 2.4% calcium. There was a slight difference between the standing crops of the heavily manured plot and those of the conventionally manured plot. The difference observed was possible due to the increase of leaf area and of leaf numbers. There also was a little difference of the tomato yield between the two plots. In the first crop the rate yield of fruit was about 15 t per 10 a in the heavily manured plot and 16 t in the conventionally manured plot. But in the second crop, 19t and 18t were produced per 10 a in heavily and in conventionally manured plots respectively. The tomato plants received heavy manure bore many numbers of flowers. In the second crop the number of fruit set was about 10-12 per truss in the heavily manured plot whereas that in the 5t FYM manured plot was about 8-9 per truss. Ripening disorder in fruit was not observed, even the K/Ca me ratio in soil solution decreased to 0.25. The sugar contents of tomato had a tendency to increase in the heavily manured plot. (p<0.1) The concentration of potassium in the stem and leaf decreased with growing stage, irrespective of the leaf position. But there were significant differences in the concentration of potassium in these organs between the two plots at each growing stage. The data in Table 4 suggested that the petioles might be capable of accumulating much higher concentration of potassium. In the 50 t plot, the petioles from all the leaf positions appeared to be approaching to a saturation point of potassium, and under these conditions potassium in the petioles were amounted to about 21 per cent of the dry matter. The concentration of potassium in the leaf blades petriole and stem increased with increasing potassium in the soil solution. But the maximum concentration of potassium in fruit juice was 4 to 5 per cent, even in the plot received 50 t FYM.

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