To increase the protein concentration of wheat grain, we applied nitrogen fertilizer at 10 days after heading and examined its effect on agronomic characteristics and flour quality. This top dressing did not affect the agronomic characteristics except for delaying of the ripening stage, but increased the 1,000 kernel weight and test weight. Protein concentration increased linearly as the amount of applied fertilizer increased, at a rate of about 0.5% per 1 gm^-2 nitrogen top-dressed. Gluten concentration increased as the protein concentration increased, irrespective of cultivar, breeding line and year. There was a significant negative correlation between protein concentration and flour color. As the protein concentration increased, flour color became gray. Nitrogen fertilizing at 10 days after heading effectively increased the protein concentration in wheat.

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To evaluate the potentials of growth and nitrogen (N) fixation of genus Crotalaria used as green manure, interspecific differences in dry matter production, root nodule formation, and N uptake among several species were investigated in field and pot experiments at Osaka, Japan. C. juncea, C. spectabilis, C. pallida, and C. incana exhibited vigorous vegetative growth, expanding leaf area and branching, and they began to flower in mid-July to early August. C. juncea had a high dry weight and a great N content at early growing stage probably due to faster root nodule formation. On the other hand, C. pallida grew slowly at the early stage due to slower nodulation, but had a high N content at the late stage. Incorporation of each species provided a large amount of N necessary for the succeeding wheat crops. Several indicators for rapid decomposition of the plants, such as total C, N and lignin contents, were investigated, and the possible increases in N supply and growth inhibition by incorporation to wheat crops were discussed. N-absorbing activity of C. juncea grown under the excess N condition (70 gN m^-2) was also evaluated. The proportion of fixed N to total N was less than 1%, and the C/N ratio was significantly lower than that in Z. mays, suggesting that this plant species could be also useful as a cleaning crop.

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Experiments were conducted to examine the ecophysiological traits of yield and ripening and the genetic backgrounds of these traits in high-yielding semi-dwarf indica rice. Field experiments were performed over four years to examine the yield and growth characteristics of these traits. A large sink size with large numbers of spikelets per panicle and a high ripening ability in the background of a large sink size were found to be two of the major ecophysiological traits that enhance the yield of semidwarf indica. High dry matter productivity after heading was suggested to be linked to a high ripening ability. To determine the genetic backgrounds that control these traits, quantitative trait locus (QTL) analysis was conducted using two different semi-dwarf indica/japonica inbred lines: recombinant inbred lines of Milyang23 (semi-dwarf indica)/Akihikari (japonica), and back-crossed inbred lines of Sasanishiki (japonica)/Habataki (semi-dwarf indica)//Sasanishiki///Sasanishiki. QTLs for larger sink size, higher ripening ability, higher dry matter production, and larger nonstructural carbohydrate (NSC) reserves in leaf sheaths and culms at heading within semi-dwarf indica alleles were detected. The effects of these QTLs probably combine to express the large sink size and high ripening ability traits, resulting in the high yields of the semi-dwarf indica rice varieties.

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This study was carried out to overcome the problems that impede genetic improvement of Lycoris. An improved ovule culture method was developed to rescue the abortive embryo in order to overcome the poor fertility in hybridization of Lycoris. Using this method, a large number of selfed and crossed plants in several species were produced, and the interspecific hybrids which used L. incarnata (sterile) as a cross parent were obtained for the first time. Cytological studies of the S₁ plants indicated that polyploidization and aneuploid reduction caused by self-pollination should be among the major factors affecting karyotype evolution in some Lycoris species. Allozyme segregations in polymorphic loci of APT, GOT and EST were observed in S₁ of five diploid species, suggesting that each of the species is originally heterozygous. The investigation using genomic in situ hybridization (GISH) was done to clarify the chromosome constitution in Lycoris. The distinction between M + T and A type chromosomes at the DNA sequence level demonstrated that genome differentiation has occurred in the genus Lycoris.

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Bread wheat has three waxy proteins (= granule-bound starch synthase I, GBSSI), which are genetically controlled by three homoeologous loci, Wx-A1, Wx-B1 and Wx-D1. Several mutant lines with waxy and low-amylose endosperm were induced from cv. Kanto 107, which has two null Wx-A1b and Wx-B1b alleles and a functional Wx-D1a allele. Starch was isolated from their grain and its amylose content, chain-length distribution profiles and thermal properties were determined. Waxy mutant lines, K107Wx1 and K107Wx2, had a new null allele named Wx-D1d on the Wx-D1 locus; a low-amylose mutant line, K107Afpp4, had a new less functional allele named Wx-D1g on the locus. Paste viscosity is markedly suppressed in waxy flour when pasting properties are measured in water using a Rapid Visco Analyzer because waxy starch swells greatly and would disintegrate at a lower temperature where α-amylase is still active. Flour yield of the waxy mutant lines was lower than that of Kanto 107 because the waxy lines had decreased starch content and increased fat and β-glucan contents more than the wild type. Possible uses of the mutant lines were described from the standpoint of starch science and genetic resource.

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Scientific techniques for determining the geographic origin of agricultural products have attracted considerable attention in recent years. The most popular origin-determining technique is based on the composition of inorganic elements, and the technique has been applied to Welsh onions (Allium fistulosum L.). The technique on Welsh onions has been developed and compiled in a manual for monitoring market merchandise earlier than other origin-determining techniques in Japan. This technique makes use of chemometric analysis on concentration ratios of 19 elements (Na, P, K, Ca, Mn, Fe, Cu, Zn, Sr, Ba, Co, Ni, Rb, Mo, Cd, Cs, La, Ce, and Tl) to Mg to determine whether the geographic origin of Welsh onions sold in Japan is Japan or China. The technique is quite practical in that it can screen geographic origin within 2 days by the analysis of inorganic elements by inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry.

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Swine wastewater has a high potential for phosphorous recovery in Japan. The pH of swine wastewater increased up to approximately 8.5 with continuous aeration, and a large part of the soluble PO₄-P, Mg and Ca was crystallized. A reactor for removing and recovering phosphorous from swine wastewater was designed with a dual function i.e., crystallization through aeration, and separation of formed struvite by settling. However, a dehydration, composting and characterization process was first needed before using sediment sludge, including struvite, on farmland, since it will settle along with huge amounts of other suspended solids (organic matter). For the recovery of pure struvite, an accumulation device was designed and its efficiency was examined. During submergence in the aeration column of the demonstration reactor, struvite cross-bridged and it accumulated on the face of the device. The struvite could be scraped off easily with only a light brushing, and was found to be approximately 95% pure. Because this device is made of a very simple structure, it should be acceptable to swine farmers.

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World aquaculture production in 2002 reached 39.8 million metric tons (Mt). However, despite a general understanding that the advancement of aquaculture is very important for food security and poverty alleviation, aquaculture in Africa is insignificant compared to the rest of the world. African aquaculture contributed only 1.2% (463 × 10³ Mt) of world aquaculture production. Moreover, our calculation based on FAO statistics revealed that the average per capita consumption of fish in Africa decreased from 9 kg in 1990 to 7.8 kg in 2001. This decrease in the per capita consumption of fish appears to be a threatening sign for food security in Africa. There are many political, economic and technical issues that are obstructing the development and promotion of aquaculture in Africa. Egypt, the desert but rice producing country, has a long history of aquaculture and is the leading producer, especially of freshwater aquaculture in Africa. Total aquaculture production in Egypt in 2002 was 376 × 10³ Mt, which supplied 81% of that in Africa. In the present review, based on the case of Egypt, we propose measures and research areas to develop and promote rice-fish culture and desert aquaculture. Rice-fish culture is a model of aquaculture styles for wet and pluvial regions, and desert aquaculture is also a model for arid and semi-arid regions not only in Egypt but also for other African countries. Poor knowledge on fish feeds and feeding technology is one of the major constraints in the expansion of aquaculture. In order to improve and increase the productivity of aquaculture in Africa, we propose measures and research subjects for developing supplementary and complete feeds using regional ingredients.

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In a rice cultivation experiment at the International Rice Research Institute (IRRI), water drainage during the fallow period inhibited the growth of paddy rice, especially during the early stage of subsequent cultivation. This symptom became more prominent when rice straw was not applied, and when the amount of fertilizer applied was small. The application of a mixture of nitrogen, phosphorus, and potassium fertilizers reduced this inhibition. The amounts of phosphorus in the growth-inhibited rice and soil were smaller than those without growth inhibition. The findings suggest that one of the factors that inhibited rice growth was phosphorus deficiency. The inhibition was associated with high soil pH and low Fe(II) content in the problem soil. There was a negative correlation between soil pH and Fe(II) content. Water drainage during fallow decreased the amount of Fe(II) in the soil because Fe(II) was oxidized to Fe(III) under oxidative conditions. During the subsequent cultivation season, the amount of Fe(II) in the soil was low and the soil pH was high. The application of rice straw improved rice growth. The phosphorus deficiency of growth-inhibited rice was associated with a small amount of available phosphorus in soil presumably because of the high soil pH and the adsorptopn of phosphorus to Fe(III) oxides in the soil.

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An algorithm for real-time prediction of river stage dynamics using a Takagi-Sugeno fuzzy system is presented in this paper. The system is trained incrementally each time step and is used to predict onestep and multi-step ahead of river stages. The number of input variables that were considered in the analysis was determined using two statistical methods, i.e. autocorrelation and partial autocorrelation between the variables. Effectiveness of the identification technique was demonstrated by a simulation study on the river stage of the Cilalawi River in Indonesia. The numerical results of the Takagi-Sugeno fuzzy modeling method were compared with the results of a conventional linear regression model. Through inspection of the results it was found that the Takagi-Sugeno fuzzy approach was more accurate in predicting one-step and multi-step ahead of river stage dynamics than the conventional multiple linear regression approach. The Takagi-Sugeno fuzzy system was able to make a proper fuzzy rule from the training data set, which might be considered as one of the main drawbacks of the Takagi-Sugeno fuzzy system. Yet, more substantial improvement certainly should be pursued through further research to improve the forecast results at greater lead times.

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Tea anthracnose, caused by Colletotrichum theae-sinensis (Miyake) Yamamoto, is one of the most serious diseases of cultivated tea (Camellia sinensis L.) in Japan. In the present study, we evaluated tea plants genetically resistant to anthracnose by using a novel wound-inoculation assay. Conidia of C. theae-sinensis were suspended in an adhesive mixture consisting of potato-sucrose broth and methylcellulose 400 cP (3% w/v). Detached mature tea leaves were wounded crosswise by a screwdriver with an adhesive conidial suspension. Inoculated leaves were cultivated on ROOTCUBES^® growing medium for 2 weeks in a growth chamber. The degree of resistance was estimated from lesion size. Five hundred tea genetic resources at the Makurazaki Tea Research Station were assayed in screening for anthracnose-resistant tea plants. Most of the foreign-introduced tea plants showed resistance, whereas native Japanese tea plants showed wide variation in the resistance to anthracnose. These results suggest that crossbreeding of native Japanese tea cultivars with foreign introduced varieties will be useful for breeding anthracnose-resistant tea plants of suitable quality.

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Four female Holstein cattle (Holstein, average body weight (BW) 359 kg), four castrated male native cattle (Native, 257 kg) and four castrated male swamp buffaloes (Buffalo, 543 kg) were subjected to urea space measurements to determine body composition of the different animals and to investigate the effect of 48 h of water deprivation on the change of body composition in Northeast Thailand. The percentage of empty body protein (EBPRO) compared to empty body weight (EBW) was similar among Holstein, Native and Buffalo. The percentage of empty body water (EBH₂O) was the highest in Native, while the percentage of empty body fat (EBFAT) was the highest in Buffalo. After the dehydration, mean BW decreased in Holstein, Native and Buffalo, and not only water but also protein and fat were mobilized. The percentage of EBPRO was similar among Holstein, Native and Buffalo; however, the percentage of EBFAT was the highest in Buffalo and the percentage of EBH₂O was the highest in Native. After dehydration, the percentage of EBFAT decreased and the percentage of EBH₂O increased in all animals.

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Levels of highly-unsaturated fatty acids, the most important nutritional factors in fry production of marine fish, were compared between hatchery-produced and wild-caught milkfish Chanos chanos fry. The most striking difference found between the fry was in docosahexaenoic acid (DHA: 22:6n-3) levels: DHA levels in hatchery-produced fry were only 37% and 18% of those in wild-caught fry in the polar lipids and neutral lipids, respectively. However, high DHA levels were detected in ovary and spawned eggs from hatchery-reared broodstock. Investigation on the time course change in DHA levels of hatchery-produced fry revealed that the DHA levels of polar lipids drastically declined from 25% at day 0 posthatching to 5% at day 14 posthatching. Nannochloropsis sp. and rotifers Brachionus sp., which were used as live food from day 2 to day 14, did not contain DHA with relatively high eicosapentaenoic acid (EPA: 20:5n-3) levels. DHA level was restored to 13% in 45-day old fry by feeding of formulated diets with a substantial amount of DHA from day 15. Thus, the lack of DHA in the live food appears to lead to the low DHA level in hatchery-produced fry. On the other hand, the cost of DHA enrichment for one milkfish fry was estimated to be 2.6 Philippines centavos, which is equivalent to about 10% of the market price of milkfish fry. The increase of the production cost might not be accepted in domestic hatcheries under competitive marketing with imported fry. Financial and marketing support by the government will be one of the measures to encourage the stable production of domestic milkfish fry with high quality in the Philippines. It is also necessary to conduct institutional campaigns to inform local fry producers and milkfish farmers of the importance of DHA-enrichment.

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