Somatic embryos were produced using aseptic seedlings of wild Cyclamen species. The seeds of 18 wild Cyoclamen species were cultured in the dark at 15-20°C until germination, and then maintained under a 16/8 light/dark photoperiod (20-30μmol m^-2 s^-1 provided by fluorescent lamps) at 24°C. Modified MS medium supplemented with 30.0gl^-1 sucrose and 3.0gl^-1 gellan gum was used for culture of aseptic seedlings. The seeds of C. balearicum, C. creticum, C. intaminatum and C. repandum did not germinate. Aseptic seedlings were obtained from 14 wild Cyclamen species : C. africanum, C. cilicium, C. coum, C. cyprium, C. graecum, C. hederifolium var. album, C. libanoticum, C. mirabile, C. parviflorum, C. persicum, C. pseudibericum, C. purpurascens, C. rohlfsianum and C. trochopteranthum. Sectioned petioles and leaves from the seedlings were inoculated on two types of induction media. The induction was carried out in the dark at 24°C. Among the 14 species, only C. cyprium, C. libanoticum, and C. parviflorum did not produce calli. The calli were subcultured and transferred to a somatic induction mealum without plant growth regulators. Variations in the type of callus, the frequency of callus formation and the potential for somatic embryogenesis were observed among the species. Somatic embryogenesis was achieved in C. africanum, C. cilicium, C. persicum, C. rohlfsianum and C. trochopteranthum and shoot formation in C. africanum and C. hederifolium var. album for the first time in this experiment.

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Changes in the evapotranspiration (ETP) of stock (Matthiola incana R. Br.) cv. White Dorse seedlings in a cell flat were measured, and regression analyses were conducted to investigate the relationships between ETP and environmental factors (solar radiation ; SR, saturation deficit ; SD and air temperature ; AT).
In each sowing month, ETP was positively correlated with SR, SD and AT. Coefficients of determination (R²) were higher than 0.81 in SR throughout the year and larger than those in SD or AT in most sowing months. Seasonal variation of R² in the regression lines was also lowest between ETP and SR compared to the other two factors. Thus, ETP was strongly affected by SR in each sowing month.
When the yearly data were pooled, the regression line between ETP (y;mg·plant^-1) and SR (x;MJ·M^-2) was expressed as follows ; y = 276.2x+24.1 (R²= 0.873). Although R² of a multiple regression equation became 0.921 when SD and AT were included as explanatory variables, there was little difference between the values of R^-2-. A simple regression line of ETP and SR could estimate ETP.
Change in ETP during seedling growth caused by the increase in the total leaf area was only 1.7 fold in comparison to changes in total dry weight and leaf area which were 10 and 7 fold, respectively. ETP at night was considered negligible in the estimation of ETP.
When the transplants of stock are grown with an automatic fertigation system for a cell flat (12ml cell volume), supplying every 5 to 6 MJ·m^-2 cumulative solar radiation may be a suitable value for fertigation frequency.

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We demonstrated the practical utility of solar radiation mediated fertigation control for transplant production in a cell flat with an automatic ebb-and-flow fertigation system. Furthermore, we investigated seasonal changes in growth and productivity of stock (Matthiola incana R. Br.) cv. White Dorse as affected by fertigation frequency controlled in response to solar radiation (5 or 10 MJ · m^-2) and scheduled time course (once or twice per day).
The shoot dry weight of transplants and fresh weight of cut flowers were higher in plants fertigated with every 5 MJ · m^-2 of solar radiation, sown between late April and late July. In plants sown during other periods, there was no significant difference in growtn and productivity among plants fertigated differently. When the plants sown in June were fertigated twice per day, the exposure was 5 MJ · m^-2 in average of cumulatlve solar radiation from fertigation to subseauent fertigation. However, the maximum cumulative value exceeded 8 MJ · m^-2. Water stress caused by the high solar radiation accompanied by high temperature and large saturation deficit may have resulted in reduced growth of the transplants and decreased quality of the cut flowers.
When the stock transplants were grown in a cell flat (220 cells of 12ml cell volume), suffcient but not excess fertigation could be obtained by supplying nutrient solution every 5 MJ · m^-2 of solar radiation with an automatic ebb-and-flow fertigation system.

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Seed fertility, growth period, yield and other characters were investigated in amphidiploid lines and sesquidiploid lines derived from Brassica rapa (2n= 20 AA) and B. oleracea (2n =18 CC) for edible flower stem, and the possibility of breeding a commercial variety with edible flower stem is discussed in this study. Seed fertility was still low in amphidiploid lines, however, some lines with high seed fertility and self-incompatibility were obtained, which can be used as parents in the further breeding of hybrids. Seed fertility in backcross of amphidiploid lines with A genome lines was higher than that in the self-pollination of amphidiploid lines. It was considered that sesquidiploid lines possess greater commercial value than amphidiploid lines. Although amphidiploid lines and sesquidiploid lines expressed a late mature character compared with their diploid lines, early and medium mature lines were obtained by using A and C genome lines with short growth duration as parents. Some amphidiploid lines and sesquidiploid lines showed strong heterosis, especially in the total plant weight, but the edible proportion of these plant was lower than that of their parents. Sesquidiploid lines were smaller in plant size, and were more suitable to high density planting than amphidiploid lines. Unit yield of the flower stem and edible proportion rate of sesquidiploid lines increased when they were grown at the optimal density. It is possible to obtain commercially valuable varieties of amphidiploid lines or sesquidiploid lines using pure amphidiploid lines selected in seed fertility, growth period, yield and other characters as the parents.

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Differentiation of rhizome into shoots occurred in Murashige and Skoog' medium containing 0.01-0.3μM jasmonic acid (JA), 0.01 and 0.03μM metyl jasmonate (Me-JA) and 0.01-0.3μM cucurbic acid (CUC), respectively. Differentiation was especially marked at 0.03μM of JA and 0.01μM Me-JA. Formation of protocorm-like bodies (PLB) from rhizome cultures observed at all treatments except for control treatment (growth regulator free). Higher concentrations of JA, Me-JA and CUC were effective for PLB formation. The average number of PLBs was highest at 3μM Me-JA. The rate of PLB formation was 100 percent at 1 and 3μM MeJA, and 0.3-3μM CUC treatments. Higher concentrations of Me-JA and CUC inhibited branching of rhizome cultures. Branching of the rhizome was completely inhibited by 0.1-3 μM Me-JA and 1 and 3μM CUC.

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In part 1 of this series, a sensing system consisting of a laser scanner and infrared sensors was manufactured and tested. The laser scanner was moved up and down by a lift to obtain a three-dimensional distance data, and the infrared sensors were used to detect the presence of human.
In this paper, an algorithm for discriminating human bodies was investigated. From the results, discrimination was achieved even when human bodies overlapped each other crosswise with some distance between them.
Furthermore, manipulator control experiments for obstacle avoidance were carried out to confirm effectiveness of the sensing system. First, the distances and the shapes of objects around a robot were measured by the laser scanner, and an avoidance motion of manipulator decided. Secondly, the manipulator moved while avoiding the object. The degree of danger was calculated when infrared sensors detected a human body around the robot, which then triggered adjustment of the speed of manipulator tip. From the experimental results, the manipulator avoided obstacles within its operating area and changed its speed according to the value of degree of danger.

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