The deep seawater is a profitable natural resource with the stable advantages of low temperature, nutrient-rich and purity and has been applied to many kinds of industry and product. In the processes producing the mineral-enriched table salt and drinking water from the deep seawater, the concentrated deep seawater is abundantly discharged, which is highly enriched in not only Na⁺ but useful minerals such as Mg²⁺, K⁺ and Ca²⁺, etc. Therefore, effective application of the concentrated deep seawater has been required, and in this study, a suitable application of the concentrated deep seawater to the production of high quality tomato was examined. Tomato plants (Lycopersicon esculentum Mill.) were grown by soil-less culture with the nutrient film technique (NFT), where the short-term salt stress was induced by applying the concentrated deep seawater. For only two weeks at the stage of rapid fruit growth, the concentrated deep seawater was added to the standard nutrient solution to increase the electric conductivity of the nutrient solution from 1.2 to 13.5 dS m^-1. From physiological analyses of the fruit quality, it was suggested that the short-term salt stress treatment with the concentrated deep seawater at the stage of rapid fruit growth can bring high quality fruits enriched in sugar, minerals and good flavor without occurrence of extremely small-sized fruits and blossom-end rot.

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The objective was to establish accurate and highly reproducible measuring conditions and analytical methods using an XYZ chemiluminescence system, which has been considered for use in the evaluation of food functionality such as hyperoxidation and anti-oxidation. Standard photon emission in the XYZ system is a high level of 10⁶ cps, consisting of two types of emissions: primary emission with a peak observed immediately after mixing the three reagents, and a secondary emission showing an asymptotic value which then approaches an almost constant level. It is important to make the time needed for addition of the reagent, which is a factor that can influence the emission curve, uniform and as brief as possible. Standard photon emission had a wavelength from 540-860 nm, and notably showed peak intensity of luminescence at near 671 nm in the early stages of photon emission, but there was not so much differences between the wavelengths of the primary and secondary emissions. It was thus assumed that the primary emission was a phenomenon resulting from the mixing of components of the reagents, that occurred irrespective of ambient oxygen concentration, while secondary emission was dependent on ambient oxygen level. Peak photon emission which is easy to identify and measure rapidly, may be desirable for use as an indicator. It appears that addition of the reagents from the outside into the box and carrying out continuous measurement from the time of reagent addition are essential to obtain reliable values, since peak photon emission is observed 10 to 25 seconds after mixing the three reagents.

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The development of the large-scale aquatic seed production system which is provided with a large amount of natural microalgae as the initial food organisms is indispensable for the advancement of aquaculture. In the present study, a food microalgae culture system was developed and tested for the development of oyster seed production plant. To achieve an effective microalgal photosynthesis, high frequency three-band fluorescent lamps were installed on both sides of the 500 l culture tank. The luminaire has the optical dimmer function, and an average vertical side surface PPFD of 300 μmol m^-2 s^-1 was obtained on the sides of the culture tank though the luminaire was on 100 % output. A moderate optical radiant environment in the culture tank was secured by using inverter lighting method for the microalgae in culture stage, according to the optical penetration change with the growth of the microalgae population, and it succeeded in power consumption because of a great improvement in shortening the culture period and increasing the culture capacity. A daily output of 2000 l (8 × 10⁶ cells ml^-1) microalgae can be produced in this culture system, which is composes of thirty two 500 l culture tanks. Thus an annual production capacity of 12 million oyster seedlings (shell height: 3 mm) can be achieved.

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To find out candidates of attractants for rice stink bug Stenotus rubrovittatus, the emissions from five grass species Echinochloa crus-galli var. formosensis, E. oryzicola Vasing, E. crus-galli var. caudata, Setaria faberi, S. glauca and Digitaria ciliaris were analyzed with a gas chromatography mass spectrometer (GC-MS). (Z)-3-Hexenal and (Z)-3-hexenol were emitted by all the plants of which leaves or ears were wounded. Hexanal, (E)-2-hexenal and (Z)-3-hexenylacetate were emitted by E. crus-galli var. formosensis, E. crus-galli var. caudate and D. ciliaris. The rice stink bag preferred D. ciliaris, which emitted (Z)-3-hexenylacetate in a largest amount among the grasses tested. When the rice sting bags were caged into the enclosure bag containing D. ciliaris, linalool and cineol were identified. They were emitted either from the rice sting bags or from the grass. In addition to (Z)-3-hexenylacetate, these compounds can be candidates of attractants for the rice stink bug.

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