This study was undertaken to promote saikosaponins accumulation in the leaves of a medicinal plant, Bupleurum falcatum, grown in solution culture. Effects of air temperature, relative humidity (R.H.), photosynthetic photon flux density (PPFD), photoperiod and CO₂ concentration on growth and saikosaponin production were investigated using growth chambers with fluorescent lamps. Maximum leaf dry weight (mg⋅plant^-1) and saponin content (mg⋅plant^-1) were obtained at 25/25°C (photoperiod/dark period air temperature) . The growth was proportional to R.H., while saponin concentration (% dry wt) was gradually decreased with the increase in R.H. Therefore, saponin content reached a peak at 80% R.H. Leaf dry weight changed with photoperiod from 12 to 20 h⋅d^-1. Further extension of photoperiod suppressed the growth, however. Increase in PPFD gave high saponin concentrations. A low PPFD (106μmol⋅m^-2⋅s^-1) and a photoperiod of 20 h⋅d^-1 provided high efficiencies of dry matter production and saponin production. There was no effect of CO₂ enrichment.

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In order to analyze environment inside open type poultry house in winter season, measurement of temperature and NH₃ gas concentration was carried out in an open type poultry house in Ehime Prefecture from 27th to 28th in December of 1993. Cross section and plan of 2nd floor of the poultry house are shown in Figs. 1 and 2. Numbers in Fig. 2 indicate measurement points. Twenty-two thousand and five hundred White Leghorns were raised in the poultry house. Height of manure on shelf was about 35 cm. Weight water content of the manure on shelf was about 78% and that of manure at 1st floor was about 64%. Curtain was closed for maintenance of inside air temperature except the time between 11: 24 and 12: 14. Figure 3 shows diurnal changes in temperature of air at 2nd floor, air at 1st floor, outside air, the manure on shelf and the manure at 1st floor. Figure 4 shows diurnal changes in NH₃ gas concentration in middle cage, at 1st floor and 2 cm above the manure on shelf at the point 5. NH₃ gas concentration in middle cage was higher than 20 ppm except the time when the curtain was open. NH₃ gas concentration in middle cage was higher than that at 1st floor. It is considered to be caused by NH₃ gas generation from the manure on shelf. Figure 5 shows diurnal changes in NH₃ gas concentration in middle cage at the points 4, 5 and 6. When the measurement was being carried out, air movement inside the poultry house was very slow because of the closing of the curtain and direction of the air movement was from the point 6 to the point 4. It caused higher NH₃ gas concentration at the point 4. Horizontal distribution of NH₃ gas concentration in middle cage is shown in Fig. 6. It is considered that higher NH₃ gas concentration at the point 4 was due to the very slow air movement inside the poultry house. Vertical distribution of NH₃ gas concentration at the point 5 is shown in Fig. 7, indicating that NH₃ gas generation from the manure on shelf causes higher NH₃ gas concentration at 2nd floor.

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The purpose of this research is to clarify the effect of shade on the growth, fruit yield and dry matter partitioning to plant organs of single truss tomatoes, Licopersicon esculentum Mill. cv. “House Momotaro.” Plants were grown in a greenhouse under three shade levels (0, 50 and 70%) from May to June (Exp. 1) and under four shade levels (0, 25, 45 and 80%) from September to November (Exp. 2) . In both experiments, plant dry weight decreased as shade level became more intense. Also, fruit yield and dry plant organ weight at the harvesting period reduced as the shade level increased. However, there were no marked differences in the proportion of organ dry matter distribution among different shade levels with the exception of 80% shade plants, which had no fruit. Further, the heavier shade increased the ratio of dry matter partition to leaf for the earlier period from 10 to 40 days of shading in Exp.
2. On the other hand, in the plants grown under 0, 25 and 45% shade levels, the ratio of dry matter partition to fruit for the latter period of Exp. 2 were higher than those of the plants for the earlier period. The plants under 45% shade partitioned the highest proportion of dry matter to fruit among the four shade levels during the harvesting period in Exp. 2.

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To clear effects of injury and plant hormone treatments to mother-scale on the bulblet formation of Lilium japonicum Thunb. the experiments were conducted. The scales cut off a part of abaxia and the edge of the mother-scale were used as explant. And they were cultured on MS medium without plant hormones at 24°C for 8 weeks under continuous light of 20 μmol⋅m^-2⋅s^-1. The number of bulblets formed on the explant was about twice of control and there is a significant difference between the injury-treatment and control. The mother-scale was cut into 8 pieces of explant from basal to apical portions. The explants were planted on MS medium containing 2, 4-D 1.0 mg/L and kinetin 0.1 mg/L, 2, 4-D 0.1 mg/L and kinetin 1.0 mg/L, or without hormones. And they were cultured for 8 weeks under the same conditions as the experiment 1. The combination of 2, 4-D 1.0 mg/L and kinetin 0.1 mg/L exhibited the most effect on the bulblet formation. Size of bulblets on the basal part of the scale was the largest in all explants and the number of bulblets formed on the middle part was more than ones in the basal and apical parts of the scale.

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The effects of CO₂ enrichment (700-900 ppmv) on the sugar concentration and acid invertase activities in tomato (Lycopersicon esculentum Mill. cv. Lady First) fruits were studied. The CO₂-enriched fruits contained significantly higher concentrations of glucose and fructose than the control (250-400 ppmv) . There was no significant difference in sucrose concentration. The acid invertase in soluble fraction showed higher activity than that in the cell wall bound fraction. The increase in invertase activity from 50 days after anthesis was accompanied with the changes in reducing sugar concentrations. Furthermore, the CO₂-enriched fruit showed higher invertase activity than the control. It is concluded that CO₂ enrichment improves sugar concentration and enhance fruit color due to increasing photosynthesis as shown by the elevated invertase activity.

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Texture observed in images of canopy from close distance is expected as the significant source of information which represents the recent status of growth plants, and it has the advantage of easiness of analysis of its characteristics. We evaluated the applicability of PSM at various growth stages through the estimation of the species composition in the pasture field mixed with orchard grass and white clover and the plane heterogeneity of growth in the pasture fields of each species. The coefficient of correlation between textural features and the species composition exceeded 70% at the elder growth stages in which vegetation ratio exceeded 60%, while textural features could not show significant correlation at the younger growth stages. Further, the textural feature which corresponds to the shortest spacial wavelength showed the significant correlation with the plane heterogeneity despite the growth stage.

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Effects of light break on the growth and flowering of Gerbera hybrida Hort, were examined under the soilless culture during the fall to winter season. The midnight light break treatment was conducted for 1 h from 23: 00 to 0: 30. The appearance of lateral shoots was considerably reduced by the light beak and therefore, number of flower stalks and leaves were less than those under the natural photoperiod. The initial flowering under the light break delayed slightly compared to that under the natural photoperiod.

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