Energy consumption is a major economic concern in greenhouse crop production, especially during the winter for growers in cold climatic regions. When the cost of energy increases, growers are inclined to decrease the greenhouse temperature to reduce daily energy consumption. However, no clear criteria or energy-saving strategies are available when energy cost is considered in terms of energy consumption per plant during the total growing period. Determining energy consumption to produce a plant is not straight forward ; when greenhouse temperature increases, time to flower decreases and energy consumption per day increases.
We developed a model that predicts total energy consumption to produce a plant by combining an energy consumption model and a plant growth model. The energy consumption model outputs the required energy to heat a greenhouse to a specific temperature using climatic data inputs, such as drybulb temperature, relative humidity, solar radiation, and wind speed. The model also predicts greenhouse temperature when solar radiation heats the greenhouse above the temperature setpoint, even without heating. The plant growth model describes the quanti-tative relationship between greenhouse temperature and plant growth rate.
A simulation study was performed with the energy consumption and plant growth modelsusing measured climate data in Michigan, USA (lat. 43°N).From January to May, total energy consumption per plant is predicted to increase as greenhouse temperature decreases, assuming that temperature does not exceed that for optimum crop development. Crops take longer to flower as the greenhouse temperature decreases, and this additional time in the greenhouse occurs during cold periods of the year. Therefore, this simulation indicates that reducing greenhouse temperature to reduce daily energy consumption is actually counterproductive, as the total energy consumption to produce the crop actually increases.

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Protocorm-like body (PLB) of Cymbidium finlaysonianum Lindl. (epiphytic species) and rhizome of Cymbidium kanran (terrestrial species) were cultured on modified Murashige and Skoog (MS) medium supplemented with various concentrations of sucrose and trehalose. Shoot differentiation in PLB cultures of C. finlaysonianum are enhanced by the addition of trehalose at concentrations of 10g/l and 20g/l. Sucrose at concentrations of 10g/l and 20g/ l had lesser effects on shoot formation from PLB cultures. Root formation from shoots developed from PLBs was significantly promoted at treatment of 5g/l trehalose. Shoot differentiation from rhizome cultures of C. kanran was significantly promoted by the addition of trehalose at concentrations of 10, 20 and 40g/l. Root formation from shoot developed from rhizome occurred in the presence of trehalose at concentrations 5, 10 and 20g/l. Sucrose had no effect on root formation from shoots developed from rhizome cultures.

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Effects of ceramics in water purification were evaluated. All ceramics materials tested suppressed the growth of algae. This effect was particularly strong with the magnesium oxide-added ceramics and with FIB-25. pH was higher in the fields treated with ceramics containing magnesium oxide. EC tended to be lower in the fields treated with ceramics containing magnesium oxide and in the FIB-25 treated fields. The addition of ceramics containing magnesium oxide to soil resulted in markedly improved water quality through suppression of algae growth and adsorption of phosphorus. This ceramics is promising as a means of improving water quality.

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The motion of paddy from the inlet of the impeller blade to the husking board is very much complicated. It is said that the husking process is almost equal to the process of energy consumption, due to the friction between the husk and the impeller blades, and the impact energy due to the collision of paddy to the husking board. Although impact forces mainly influence the husking process, these are also the major cause of damage to the rice. Alternative methods of investigations are necessary to reduce the influence of impact forces on the grains. Theoretical approach was applied to analyze a single grain of rice to find out the longitudinal length effect of the impeller blade in this study. By increasing the peripheral area, the revolutionary speed of impeller blade (rpm) was decreased, and conversely less shock or impact energy was produced for the husking purpose. Using two impeller units with 8. 5 cm and 15. 5 cm radius for this, a comparative evaluation was done for the validation of the theory. Ultimately less damage was found on the rice kernels when a larger peripheral area impeller blade was used even with the same peripheral speed (m/s) of the impeller.

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Plant growth rate can be controlled by adjusting both the light quality and during light and dark transition. Light intensity and time also have an effect on growth rate.
We investigated the effects of low-intensity light irradiation of specific frequency on the growth and inorganic contents of lettuce in the field. Lettuce was cultivated using three types of nutrient solution (complete nutrition, NO₃-N-excessive, NO₃-N-deficient). Light sources were red and yellow LEDs, which are low-cost artificial light sources used in plant production. Leaves were irradiated by pulsed LED-light for several hours each day.
Red and yellow LED-light stimulation of specific frequency (20 Hz, 50 Hz) increased the lettuce yield in nutrient solutions with lower NO₃-N concentrations, despite of the fact that the chlorophyll in lettuce does not response much yellow light. Changes in light stimulation frequency affected NO₃-N concentrations in lettuce sap. These results suggest that stimulation by red or yellow LED-light in the field has a positive effect on photosynthetic activity.

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The steady domestic demand for grafted vegetable seedlings appears to be due to the increasing number of aging farmers, who tend to buy grafted seedlings. In the prosperous horticultural regions of Europe, grafted seedlings have started to be utilized more aggressively as environmental problems have become obvious.
Under these domestic and foreign circumstances, most seedling producers depend on manual seeding by many employed labourers for cucurbitaceous scion and rootstock seeds, especially using elliptical and big seeds as there is not yet a seeder adaptable to those seeds on the market.
For manual seeding, farmers need to put each seed in the right direction in each cell by arranging the longitudinal axis and the germ pore side to prevent mutual shielding of cotyle-dons.
This report introduces the results of a market investigation and the development of a seeder that is adaptable to cucurbitaceous seeds and able to arrange the direction of the longitudinal axis.

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In part 1 of this series, a harvesting robot consisting of a 5 DOF polar-coordinate manipulator, a harvesting end-effector using sucking force, a visual sensor and a traveling device was manufactured and tested with strawberry grown on table top culture. From the results, it was observed that the table top culture was a suitable cultivation method for robotic operations because there were few obstacles around the target fruits, and that harvesting using a sucking force inflicted no damage on the fruits. However, it took the robot 14 to 20 seconds to harvest a single fruit because of the complicated construction and control method of the manipulator.
In this study, a cartesian coordinate manipulator suspended under the planting bed of strawberry was employed in order to simplify construction and control method of the manipulator intended for practical use. The robot was capable of moving along the planting bed without a traveling device because one prismatic joint of the manipulator played the role of a traveling device. Furthermore, depth measurement by a visual sensor was simplified because distance between the robot and the fruits was kept approximately constant by suspending the robot under the planting bed. Harvesting experiments were conducted in a greenhouse by using the manipulator equipped with an improved end-effector and a visual sensor. From the results, time required to harvest a fruit was reduced to around 10 seconds because of the simplified construction and control method of the manipulator.

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The capability of higher plants to improve the quality of artificial wastewater (Otsuka-House Fertilizer Series A medium, 0.5 dS m^-1) varied with the species and with the growth conditions. In the warm season, water convolvulus showed more activity than mint, jute or water hyacinth (a plant widely used against eutrophication). In the cold season, calla lily showed the highest level of activity. Thus, the plant species need to be selected depending on the season. Water convolvulus is a green leaf vegetable with medicinal value, and calla lily is an ornamental plant. Both plants can be effectively used to improve water quality and as useful resources after harvest.

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