In designing greenhouses, visualization of the greenhouse by computer graphics is important for estimating the light environment, spacing of crops, etc. The modeling of plant shapes has been difficult but recent progress in plant modeling technique enables the realistic modeling of plant shape. In this study, the practical applicability of the technique was tested by creating greenhouse images. AMAP (graphic design system with high-precision plant modeling technique) was used for visualization. The result shows that photo-realistic simulation of the design was possible using this method.

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The biologically active compounds (chlorogenic acid, caffeic acid, chicoric acid and 3, 5-dicaffeoylquinic acid) in lettuce (Lactuca sativa L.) were determined by high performance liquid chromatography (HPLC) to evaluate the difference between ten kinds of cultivars cultured with hydroponic solution at two levels of electric conductivities (EC ; 2.0 and 3.5 mS/cm). All the HPLC profiles of the cultivars tested showed the peaks at the same retention time ; there being no qualitative difference with the EC level. However, the peak areas differed with the cultivar. Particularly, a cultivar 'Chimasanchi' was found to contain much larger amounts of chlorogenic acid and 3, 5-dicaffeoylquinic acid than the others. The main component of 'Chimasanchi' was chlorogenic acid, while that of the others was chicoric acid. In addition, higher concentrations were obtained in the cultivars cultured with 3. 5 mS/ cm than with 2.0 mS/cm. Therefore, the concentration of secondary metabolites having biologically activities in vegetables may vary with the cultivars and also with the EC level of the culture solution, indicating that they could not be controlled by the chemical breeding and/or the culture condition.

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Installation of three-dimensional plant architecture expands the possibility of more precise description of the models of light environment, plant growth, etc. In the present study, the number and length of internodes of some varieties of soybean plants were measured and analyzed. Distributions of internode length were fitted by binominal and negative binomil distribution and characteristics of the branching were expressed using Marcov chain. It is shown that results of these methods agree well with the measurement. These methods enable more precise generation of plant architecture and will be applicable to other crops.

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A method for evaluating tomato ripeness, utilizing its surface color, was developed using a machine vision system with color image processing capability and a multi layered neural network-based software system. The tomato ripeness was classified into four categories; unripe, half ripe, full ripe and over ripe according to the standard commercial classification for manual sorting. Over ripe means the fruit has lost its freshness. Three color specification values, i. e., lightness L^*, chroma C ^* and hue H were calculated from the RGB gray levels of a captured color digital image of a tomato by an on-line image processing system. Only 0.2 to 0.5 % of total surface area of a fruit is needed for color image sensing of the classification. The area size representing 0.5% of the total area was covered by 243 pixels of resolution. A three-layered neural network with four hidden layer units gave a satisfactory performance at 18000 times of BP (Back Propagation) learning. The total processing time from the image capturing to the final output for a single fruit was 0.45 seconds. The recognition rate for the ripeness classification using this method was as high as 93 %. A recognition rate of only 77 % was obtained by the multiple regression model tested. The present work provides another example to strengthen the area of neural network application research on machine vision systems including agricultural robotics, postharvest and processing systems.

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Hippeastrum hybridum Hort. is a well known ornamental plant, difficult to propagate by conventional methods such as twin scaling because of low propagation rate and virus diseases. The regeneration ability of various parts of the plant such as bulb scales as the source of clonal propagation is of interest. The regeneration of new plants from excised bulb scales in vitro has been previously reported, but these methods are not suitable for production of large number of plantlets for commercial cultivation.
Herein, the effects of abscisic acid (ABA) and light irradiation on the regeneration and growth of Hippeastrum hybridum in shake culture were investigated. The bulb segments were inoculated in MS liquid medium supplemented with various concentrations of ABA and cultured at 21°C for 13 weeks under continuous irradiation or complete darkness. Cultures proliferated well in the medium without ABA. Production of plantlets was inhibited especially at high ABA concentrations (1 to 10 mg/l), and at worst inoculated bulb segments became deteriorated. To stimulate the regeneration and growth of Hippeastrum hybridum in vitro, use of MS liquid medium with or without ABA (0 to 0.1mg/l) under continuous light conditions was required. Bulb segments cultured in a 10l glass jar fermentor containing 5l of MS liquid medium without ABA under continuous light conditions showed sufficient propagation.

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The effects of the number of inoculated bulbscales and the culture strain on differentiation and growth of newly formed bulblets of Lilium auratum Lindl. in tissue culture were investigated.
The bulbscales dissected from tissue cultured bulblets were transferred successively to 300 ml flask containing 150 mE modified MS liquid medium, 5, 10, 15, 20, 25 and 30 bulbscales per flask, and cultured for 3 months. Fresh weight of bulblets increased with the decrease in the number of inoculated bulbscales.
Regeneration and growth of bulblets were also affected by the culture strain. Established strain collected in Fukushima town, Hokkaido Pref. tended to form multiple bulblets and to show callus induction, but not the strains collected in Mishima city, Shizuoka Pref.

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The market price of H. marmoreus rose during the first 9 years of its supply to the market, from 1973 to 1982, and then fell (Fig. 1). It sells at a very high price during the autumn season, and at a low price during the summer season (Fig. 2).
Let R_p be the year of grace, and h be the membership function of fuzzy model, the fuzzy equation X (R_p) predicts the future market price of H. marmoreus by analyzing some data from 1982 to 1992.
X (R_p) = (130.72, 4.7189/ (1-h)) _L- (21.250, 0.000) _L ln (R_p-1981) (7)
These data and the equation are shown in figure 3.
From this equation, the estimated market price (yen) per 100 g of H. marmoreus is (69. 9, 74. 6, 78. 9) in 1995. On the other hand, the production cost per 100 g of H. marmoreus is (40. 1, 58. 7, 99. 6). These T. F. N. are shown in figure 4. As a result, the probability that the production cost is less than the estimated market price, is 75. 5 %. Conversely, the probability that the production cost is more than that is 14. 7 %. In the next place, Tables of cash income of 15 years hence is made by using the fuzzy equation X (R_p) and fuzzy yield (table 1). Let E be the borrowed capital ratio, I be the amount of initial investment, and j the depreciation ratio. The equal repayment (B) is as follows;
B∑¹⁵_i=11/ (1+j) _i=B1- (1+j) -¹⁵/j= (1-ε) ∑^o_1=-1I_i/ (1+j) ⁱ (13)
In this table, the cash incomes are given in values of n years hence. So, the values are changed into present values. Let α be the cut level of T. F. N. showing cash income, In be the lowest limit of it, Sn be the highest limit of it, ii be the lowest limit of discount ratio, si be the highest limit of it. Then, the cumulative cash income (Γn) is as follows;
Γ_n (α) =∑ⁿ_i=0 [I_i (α) / (1+S_i (α)) ⁱ, S_i (α) / (1+i_i (α)) ⁱ ](15)
In the table 1, the T. F. N. of accumulative cash income (ten thousand yen) par 15 years by the cash income changed into present values is (587, 2900, 4405), and it by the representative ordinary number of cash income is (2727, 2846, 2969) (Fig. 5-8).
We conclude from the analyses described above that the economic condition of this mushroom factories is very good.

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