The ultimate goal of the international rice genome sequencing consortium has been successfully realized with the completion of the entire rice genome sequence in 2004. An accurate sequence totaling 370 Mbp of the japonica rice cultivar Nipponbare corresponding to 95% of the entire genome is now publicly available. Comprehensive analysis of the sequence has revealed some unique features of the rice genome. Together with other rice genomics resources, this map-based sequence will revolutionize rice biology with the rapid identification of genes responsible for many agronomic traits, genome-wide comparison with other rice species and cereal crops, and establishment of new breeding methods based on DNA markers.

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Understanding the mechanisms responsible for UV-B irradiation-induced DNA damage repair in plants is important for agricultural technology in that it will potentially enable the development of plants with enhanced growth rates and crop yields. Unlike yeast and mammalian cells, intact plants use sunlight for photosynthesis and are thus chronically exposed to the UV band wavelengths present in solar radiation. UV induces DNA damage, which can be corrected by DNA repair mechanisms such as photoreactivation and excision repair. Recently, details of several DNA repair mechanisms have become clear in plants. We made transgenic rice overexpressing genes involved in excision repair or plant-specific DNA repair, and measured their tolerance to UV-B. We found that OsUV-DDB2 and OsSEND-1 transgenic lines had higher tolerance to UV-B than the wild type. In this review, recent advances in understanding repair of DNA damage from UV-B radiation in plants and the prospects for the development of UV resistant plants are discussed.

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To develop new uses for sweet potato starch, we studied about breeding for improving starch properties in sweet potato. The amylose content of the germplasm collections of sweet potato ranged from 11.2 to 15.3%. There were varietal and geographical differences in the amylose content of sweet potato. Analysis of the varietal and annual variations in starch properties suggested that selection for pasting temperature, setback and amylose content can be effective. The variations of amylose content in sweet potato and its related diploid wild species could be increased by crossing and mutagenesis, and variants with a low/high amylose content could be selected. Furthermore, a new sweet potato cultivar “Quick Sweet” was developed, featuring low gelatinization temperatures and altered starch fine structure. Gelatinization temperatures and pasting temperatures of Quick Sweet starch were approximately 20°C lower than those of ordinary sweet potato cultivars. The chain-length distribution of amylopectin showed that Quick Sweet starch had a higher proportion of short chains (DP6-11) than the ordinary cultivars. Starch retrogradation, evaluated by leaked water percentage and hardness of starch gels after cold storage, indicated that Quick Sweet starch had excellent cold storage stability.

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Sesamin and sesamolin, oil-soluble lignans of sesame seeds, exhibit antioxidative activity in vivo and show various metabolic functions. HPLC analysis to detect the sesamin and sesamolin contents was modified to easily screen hundreds of accessions. The sesamin and sesamolin contents changed with seed maturity and were highest in the capsules at 30 days after flowering, showing large varietal difference at that time. The sesamin and sesamolin contents are an inherited characteristic. “Gomazou” was selected from the progeny of a cross between “Toyama 016”, a large seed line from Peru and “H65”, a high-lignan-content line originating in south China. “Gomazou” stably contains roughly twice as much lignan as “Masekin”, a local Kanto-region cultivar with a good yield. A physiological activity test on fatty acid oxidation in the rat liver showed that “Gomazou” more profoundly affected lipid metabolism than the control variety, “Masekin”. A high-lignan-content sesame cultivar could promote new demand as a local speciality crop and revive domestic production in Japan.

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A Windows-based system for estimating the potential nitrogen (N) outflow in a catchment has been developed. The system includes a conversion method for administrative-based data from national scale statistics, such as the agricultural census, into a catchment-based data by utilizing the geographic information system (GIS). The system calculates N loads based on the pollutant load unit (PLU) method in a catchment and converts them to potential N outflows by introducing the outflow coefficients. For the catchments of tributaries flowing into Lake Kasumigaura in central Japan, where nonpoint sources were predominant, the N loads and the potential N outflows from 1950 to 1995 were estimated. The actual N outflows from the tributaries were also estimated using the water quality monitoring data at the outlet of the tributary catchment and meteorological data. These potential N outflows and actual N outflows were compared. Results obtained were as follows. (i) Some estimates by the present method, such as the drainage area and cultivation areas of various crops in each tributary, well agreed with those estimated by other methods and published data, indicating that this method was capable of estimating catchment-based data from the administrative-based statistics. (ii) Changes in the potential outflows during the period from 1950 to 1995 reflected the changes in livestock production and methods of waste water treatments. (iii) Comparison between the N potential outflows and the actual N outflows suggested that about 47% of the generated N load which leached down to groundwater from the soil surface flowed out and that a time-lag between two outflows appeared. Thus, the developed system offered good possibilities of realistic quantitative analyses on the contribution of non-point sources to water quality on the scale of a catchment.

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‘MAKURA No. 1’ (Camellia sinensis var. assamica) is the first tea breeding cultivar that was selected for high tannin and caffeine contents from the genetic resources in the Makurazaki Station of the National Institute of Vegetable and Tea Science (NIVTS). Average tannin and caffeine contents of the 1st and 2nd crops of this cultivar were 24.6 and 5.5%, respectively. ‘MAKURA No. 1’ also has a strong floral flavor, and this trait was handed down to the progenies at a certain frequency. The results show that ‘MAKURA No.1’ can be used as a parental line for breeding cultivars with high tannin and caffeine contents and a floral tea flavor. ‘MAKURA No. 1’ was named ‘Cha Chuukanbohon Nou 3’ and registered as a parental line by the Ministry of Agriculture, Forestry and Fisheries (MAFF) in August 1998. It was registered based on the Seed and Seedlings Law in June 2002.

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Chlorophyll fluorescence has been known as one of the indicators of photosynthetic status to various environmental stresses. The aims of this study were to assess the effects of environmental factors on lettuce chlorophyll fluorescent responses (Fv/Fm) and to develop an environment optimization model for lettuce growth using a simple genetic algorithm. High values of Fv/Fm were observed when environmental factors were 22-26°C ambient temperature, 15-23°C root zone temperature, 900-1,600 ppm CO₂ concentration, 0.4-1.3 m•s^-1 air current speed, and 65-85% relative humidity. As photosynthesis photon flux (PPF) increased over 150 μmol•m^-2•s^-1, Fv/Fm values were decreased. Principle compo-nent analysis was used to estimate the combined effects of six environmental factors on lettuce growth. The developed model fitted observed Fv/Fm values with an average standard error of 1.2%. An optimal environment for lettuce growth was estimated by the model to be 22°C ambient temperature, 20°C root zone temperature, 1,578 ppm CO₂ concentration, 1.3 m•s^-1 air current speed, 216 μmol•m^-2•s ^-1 PPF, and 75% relative humidity. The Fv/Fm value can be a good indicator of plant stress level and thus a useful parameter to optimize the environment for plant growth.

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The aim of this study was to control microorganisms that cause grain degradation using ultraviolet (UV) sterilization, as a method that is eco-friendly and safe for storage without the need for postharvest application. In order to obtain practical ultraviolet sterilization, we manufactured recirculating grain sterilization equipment that uses UV irradiation. We investigated applying UV sterilization directly to microorganisms that adhere to the surface of the wheat, and then checked the quality. Sterilization tests indicated that the required sterilization time to obtain a 90% sterilization rate was 6.3 h for bacteria and 5.6 h for mold using 254 nm wavelength and 97 W/m² UV irradiance. The germination and amylo-graph tests suggested that quality was minimally affected by UV irradiation in this range.

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This paper presents the results of a survey on the situation of farmers, their problems and feasibility of heat stress techniques during storage of fruits and vegetables in Pakistan. In addition, consumer perception was also surveyed regarding availability and quality of stored fruits and vegetables. The survey, which was conducted at Dera Ismail Khan District of Pakistan′s North West Frontier Province during 2004, revealed that most of the farmers sell all their produce in the market just after harvest. This might be either due to the unavailability of storage facilities or the high cost to store low and medium value fruits/vegetables. High electricity costs and frequent power cuts further raised the storage prices. However, among different methods practiced locally, sun drying was the most popular method. Regarding consumer perception, the majority were not satisfied about availability of fruits and vegetables in the market all the year round. Lack of storage facilities, damages that occurred during transportation, improper packaging, the role of middlemen, and huge influx of produce in a short time were the major reasons given for reducing availability of fruits and vegetables to consumers on the one hand and lowering returns to growers on the other. The growers demanded subsidized governmental storage facilities to store their agricultural commodities.

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In order to prevent aflatoxin contamination in the production of kecap, an Indonesian soy sauce, the starter culture was prepared using the white-spored mutant K-1A strain induced from the aflatoxinnegative koji mold, Aspergills sp. K-1 and applied to koji making process of kecap. The number of spores developed on the cooked rice inoculated with K-1A was not so different from that of K-1. The germination ability of K-1A after storing at 30°C and 75% RH for 3 weeks was also not so different from that of K-1. While kecap koji making process took 9 days by conventional method (without inoculum), the use of the starter culture shortened the process to 3 days at room temperature. Since the inoculated strain K-1A developed white conidia (spores) during incubation, the mutant could be distinguished from contaminated aspergilli by their appearances on agar plates. The number (cfu/g) of contaminated aspergilli in the kecap koji from the environment decreased to 1/10 by using the starter culture. The kecap mash prepared with the kecap koji inoculated with the starter contained higher formol nitrogen and water-soluble nitrogen than those prepared with the koji without any starter. These results demonstrate that the use of the white-spored mutant as a starter not only contributes to the prevention of aflatoxin contamination but also improves the conventional kecap fermentation process.

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‘Earl′s Kagayaki’, an Earl′s-type melon (Cucumis melo L. var. reticulatus) with resistance to cottonmelon aphid (Aphis gossypii Glover), powdery mildew (Podosphaera xanthii (Castaggne) U. Braun & N. Shishkoff), and fusarium wilt (Fusarium oxysporum f. sp. melonis (Leach et Currence) Snyder et Hansen) was registered as melon cultivar ‘Norin Kou No.7’ and released in 2004 in Japan. The fruit weight is around 1,500 g, the shape is spherical, the rind color is greenish gray, and the skin is finely netted. The flesh is yellowish green with a desirable aroma, and the taste is superior to common Earl′s-type cultivars with the Brix value of 13 degrees. The shelf life is 5 to 7 days after harvest. ‘Earl’s Kagayaki′ can be grown in all the Earl′s-type melon production areas of Japan and also in other temperate and sub-tropical regions. This cultivar is primarily recommended for production in suburban areas, in farmlands with sightseeing tours, and by the farmers having fruits-stores. This cultivar is suitable for spring cultivation and summer-autumn cultivation under greenhouse conditions.

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A metabolism trial was conducted with four Brahman cattle and four swamp buffaloes fed with Ruzi grass hay (Brachiaria ruziziensis, 0.77% N). There was no significant difference in energy and nitrogen balances, and nutrient digestibilities between cattle and buffaloes. However, fasting heat production was significantly lower in buffaloes. Urinary excretion of allantoin tended to be lower in buffaloes than in cattle although there was no significant difference. Free fatty acid content in the blood serum during the fasting period was lower in buffaloes than in cattle although it was not different when the animals were fed. On the other hand, urea content in the blood serum during the fasting period was higher in buffaloes than in cattle.

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Water from shrimp aquaculture ponds was circulated through a mangrove woodlot, oyster beds, and seaweed ponds in biofilter experiments designed to reduce environmental loads. Though the nutrient concentrations in the shrimp culture ponds were lower than those in the other ponds in many cases, the Chl. a concentration increased explosively in shrimp ponds and exceeded 160 μg/L. These results suggested that nutrients were used for the growth of phytoplankton. The Chl. a concentration was very low in the oyster pond, and it was suggested that oyster feed actively on phytoplankton. Ammonia was always lower in the seaweed ponds than in the oyster ponds, which suggested that seaweed took up ammonia. From the nitrogen budget, 27% of nitrogen in supplied feed was incorporated into shrimp, 32% was flowed to mangrove, oyster and seaweed ponds and removed with these biofilters, and 9% was added in the aquaculture system as dissolved inorganic and particulate nitrogen. Therefore, this aquaculture system using mangroves, oyster and seaweed as biofilters was thought to be effective to reduce the environmental load.

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