The timing of heading and flower bud initiation is critical for reproductive success. In sorghum (Sorghum bicolor Moench), which is a facultative short-day plant, we propose that the thermo-sensitivity and photoperiod sensitivity genes account for the relationship between heading time and the environment. In experiments in fields and growth cabinets, the heading time of cultivars such as cv.Hiromidori accelerated with reduction in total leaf number by exposure to temperatures lower than 20°C (i.e., the opposite phenomenon occurs at over 20°C); these cultivars were designated as B-type cultivars. The flower bud initiation of cultivars such as cv.Tentaka was induced by critical daylength below 12.25 hours; these cultivars were designated as C-type cultivars. In the inheritance study using populations derived from hybrids of B-type cultivars, thermo-sensitivity for heading response was controlled by a monogenic dominant gene (T) of late over early heading. The existence of two photoperiod sensitivity genes, D₁ and D₂, which show complementary dominant effects, was found in populations derived from hybrids of C type cultivars, and the heading response of C type cultivars was expressed by the interaction both of a dominant thermo-sensitive gene (T) and complementary dominant photoperiod sensitivity genes (D₁, D₂). AFLP and RFLP analysis suggested that T was located at a genetic distance of 4.0 cM from the AFLP16 marker locus on chromosome 6.

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In autumn, winter wheat and temperate forage grasses, such as orchardgrass, timothy, and perennial ryegrass, accumulate fructan, which is a kind of fructose-based oligo- and polysaccharide. The fructan content in their crown tissue reaches more than 30% of their dry weight before snow cover, and this increase in fructan content is associated with both the freezing tolerance and the snow mold resistance of winter crops in the northern region of Japan. These crops mainly accumulate the β(2,6)-linked levan type of fructan, and their structure and composition vary among wheat and grasses. We cloned several kinds of genes encoding fructosyltransferase and fructan exohydrolase from these plants, and analysis of the expression of fructosyltransferase revealed varietal differences in wheat under field conditions and low-temperature responses in grasses. Further investigation of the control of fructan metabolism through molecular biology and genetics should lead to the development of methods for improving the over-wintering ability of these crops.

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Four quantitative trait loci (QTLs) for rice (Oryza sativa L.) heading date were previously detected by QTL analysis of progeny derived from crosses between a japonica cultivar, Koshihikari, and an indica cultivar, Kasalath. To enhance the cropping potential of Koshihikari, a leading cultivar in Japan, our team used marker-assisted selection to develop isogenic lines (ILs) with early and late heading dates. Several types of DNA marker were used to minimize the length of substituted chromosome segments containing target QTLs and to determine the genotype in the target QTL regions and in the background genome of the ILs. We developed four new ILs-Koshihikari Kanto HD1 (Hd1), Wakei 370 (Hd4), Kanto IL5 (Hd6), and Kanto HD2 (Hd5)-housing Kasalath chromosome segments of 560, 7960, 170, and 625 kb, respectively. The heading date of Koshihikari Kanto HD1 was 12 days earlier than that of Koshihikari in Ibaraki, and those of Wakei 370, Kanto IL5, and Kanto HD2 were 3, 10, and 11 days later, respectively. Most of the traits, except the heading date of the four ILs, were the same as those of Koshihikari.

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Azuki bean (Vigna angularis) and rice bean (V. umbellata) are locally important legumes that were domesticated in Asia. They are genetically closely related and therefore suitable for comparative genomics studies. The center of genetic diversity of azuki bean is in East Asia and it was most probably domesticated in Japan based on the archaeobotanical and genetic evidences. The center of genetic diversity and domestication of rice bean is in Southeast Asia. The domestication of rice bean involved fewer gene (QTLs) mutations with larger genetic effects than azuki bean. The distribution of major domestication genes in rice bean is limited to two linkage groups compared with five in azuki bean. In azuki bean the major domestication genes are abundantly detected on linkage group 9 (LG9), while in rice bean they were found on LG4. Surprisingly, many species specific QTLs were detected such as azuki bean’s erect stem QTL on LG9 and rice bean’s seed size increase QTL on LG4. Such species specific QTLs suggest the possibility that rice bean and azuki bean can provide novel genes for breeding. Comparative genomics among closely related species is an efficient way to find novel genes for breeding.

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In this study, ¹⁵N-labeled organic materials were used to evaluate the nitrogen (N) dynamics associated with the application of organic materials to paddy fields. The decomposition of three types of organic materials, namely wheat straw, rice straw, and cattle manure compost, was evaluated by using the glass fiber-filter paper bag method. The N retention rates obtained by evaluation of N content were different from those obtained by evaluation of ¹⁵N abundance. The fates of N in seven types of ¹⁵N-labeled organic materials, namely cattle manure compost, poultry manure compost, swine feces, rice straw compost, rice bran, rice straw, and wheat straw, were studied during a crop season in a warm region in Japan. The nitrogen use efficiency for swine feces, poultry manure compost, and rice bran relative to that for chemical fertilizers was as high as approximately 70%, whereas the nitrogen use efficiency for cattle manure compost relative to that for chemical fertilizers was as low as 16-19%. The N uptake from ¹⁵N-labeled swine manure compost or rice bran simultaneously applied with cattle manure compost was slower than those from swine manure compost or rice bran alone. Furthermore, I investigated the fate of N derived from ¹⁵N-labeled cattle manure compost over a period of three years in a region with a cool climate. Well-composted cattle manure compost was found to be a stable N source for rice plants for at least three years after application. A large amount of N derived from the cattle manure compost remained in the soil even three years after application.

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Parasexual recombination is thought to be one of the causes of variation in the pathogenicity of rice blast fungus, Magnaporthe oryzae, which breaks down resistant rice varieties. In this study, the virulence and fitness of parasexual recombinants of M. oryzae were examined in vitro and in the field. According to the results of the genetic analysis of the pathogenicity of parasexual recombinants of the fungus, the segregation ratios of avirulence and virulence among recombinants on rice cultivar Hattan 3 and line K59-1 were consistent with those of the sexual progeny of the fungus. This indicated that the avirulent genes of the parasexual recombinants were segregated in a manner similar to that in sexual reproduction. The fitness of parasexual recombinants derived from co-cultures of parental isolates was also investigated. The recombinants produced intermediate-sized lesions and intermediate numbers of spores between the parents on the host. Plants inoculated with the recombinant also showed intermediate disease severities between the parents in the field. Parasexual recombinants can attack a rice multiline system because their virulence and fitness is inherited from the parents.

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The lima bean pod borer Etiella zinckenella (Lepidoptera: Pyralidae) is a severe agricultural pest attacking various leguminous crops in many areas of the world. Insecticidal control is ineffective because larvae feed inside the pods of legumes and so cannot readily be reached by sprays after egg hatch; therefore, monitoring by pheromone-baited traps would assist decisions on when to spray insecticides in a more effective and efficient manner. Four components have been found in the female pheromone glands of this species: tetradecyl acetate, (Z)-9-tetradecenyl acetate (Z9-14:Ac), (Z)-11-tetradecenyl acetate (Z11-14:Ac), and (E)-11-tetradecenyl acetate. The binary blend of Z9-14:Ac and Z11-14:Ac attracts many males in Europe and North Africa but it attracts almost no males in East Asia or Australia, suggesting possible geographic variation in the pheromone communication system of this species. A recent study reexamined the sex pheromone of E. zinckenella in Japanese populations and discovered another essential component, (E)-9-dodecenyl acetate. Here, we review studies of the sex pheromone and its geographic differences in E. zinckenella and discuss the potential use of pheromones for monitoring this cosmopolitan pest of legumes.

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A subsurface dam is a facility that stores groundwater in the pores of strata and uses groundwater in a sustainable way. These dams have many merits that surface dams do not, e.g., land is not submerged to store water and there is no danger of breaching due to natural or manmade disasters. In addition, the surface area can be used in the same way before and after construction of the subsurface dam. Because of these merits, there are many underground dams in the world. This paper reviews the basics about underground dams, the construction of underground dams around the world, and the problems involved in the sustainable use of groundwater. According to a recent review of the construction of underground dams, the scale of underground dam projects has grown. Some problems with underground dams reported in the past, i.e., sedimentation, flooding, collapse, and salination, occurred because of human error, as well as the immaturity and complexity of geological features. In terms of water quality, long-term monitoring was carried out after construction of underground dams on Miyako Island, Japan. To deal with any problems, countries must exchange information gathered from their experiences in constructing underground dams.

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We have developed a near-infrared (NIR) spectrometer mountable on a head-feeding combine for measuring rice protein in real time while harvesting. The developed sensor employs reflectance optics instead of the more usual transmittance optics because (1) it operates under severe vibration and dust conditions; (2) it performs measurements in high moisture contents, low fluidity of rough rice; and (3) because of low light transmittance due to absorption by husks. The light source was a tungsten halogen lamp, with a diffusion cylinder installed so that uniform light would illuminate the sample. An Si-CCD measured the spectrum from 740 nm to 1140 nm with a post-dispersive grating. We made a calibration curve of brown rice protein from a spectrum of rough rice examined in a laboratory. The calibration curve accuracy was r= 0.87 and SECV (Standard Error of Cross-Validation) =0.47%. In the adopted measurement method, the sensor loaded the rough rice into a wide sample chamber by gravity and analyzed the loaded grain at the bottom using a reflected signal. The developed sensor was able to measure the protein content of brown rice from spectra of rough rice taken under severe conditions, e.g., a high-vibration, high-dust harvesting environment. In addition to the protein content, the rice weight and moisture content could be displayed on the monitoring terminal in real time. The accuracy of the protein content measurements in these field examinations was r=0.65 and SEP (Standard Error of Prediction) =0.22%. The SEP was far better than the SECV of the calibration, but the protein content fell in a narrow range in the field examination. Thus, we concluded that the actual accuracy was the same as the calibration.

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Superheated steam (SHS) was applied to food processing because of advantages including efficient heat transfer by latent heat, and prevention of product oxidation. SHS heating solves problems such as water absorption and dissolution of solid content from foods caused by hot water or saturated steam heating; however, it causes low product yield due to its high drying capacity. To fix these problems, a new system using SHS around 115°C and a spray of hot water micro droplets (WMD) has been developed. The SHS+WMD system has simultaneously improved the quality and yield of blanched potatoes and other vegetables. In addition, it was found that WMD increased the heat transfer efficiency of SHS. This was presumably because WMD reduced the thermal resistance of the condensed water layer on the product surface by stirring the condensate. Due to this effect, the required time for the surface pasteurization of some kinds of raw vegetables decreased. A standard plate count of bacterium on cucumber fruit decreased from 10⁵ CFU/g to 300 CFU/g with a slight texture change by SHS+WMD heating for 30 s. The SHS+WMD system is currently used in the food industry for cooking potato salad, and preprocessing meat, as well as the pasteurization of fishery products in Japan.

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This review describes the development of the multiplex PCR detection kit for Salmonella spp., Listeria monocytogenes, and Escherichia coli O157:H7 in food samples. To develop a detection assay, our research team evaluated the optimization of the pre-enrichment broth, the simple DNA extraction method, and the multiplex PCR settings. When this detection protocol was used to detect the above pathogenic bacteria, one cell per 25 g of inoculated sample was detected within 24 h. Moreover, there was excellent agreement between the multiplex PCR assay and the conventional culture method. The multiplex PCR detection assay system was confirmed to be a reliable and useful method for the rapid screening of food products for foodborne pathogens. The assay system was commercialized as a “[TA10] Pathogenic Bacterial Multiplex PCR Detection Kit”. When this kit was provided to four different laboratories for an extensive validation study, there were no significant differences in detection sensitivity among the laboratories. The detection kit will be valuable as a screening method for foods contaminated with these pathogens, and it will also be useful for identifying the sources of outbreaks of foodborne illness.

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Yersiniosis, which is caused by pathogenic Yersinia enterocolitica or Yersinia pseudotuberculosis, poses a serious problem for zoological gardens engaged in breeding nonhuman primates. In Japan, Y. pseudotuberculosis in particular frequently causes fatal infection, and affected nonhuman primates may die unexpectedly or after a very short illness. Our epidemiological study in 17 zoological gardens in Japan suggested that Yersinia pseudotuberculosis-derived mitogen (YPM), which is a kind of super-antigenic toxin, might be the cause of, or at least the most important factor in, the high mortality of breeding nonhuman primates infected by Y. pseudotuberculosis in Japan. Furthermore, seroepidemiological study proved that pathogenic Yersinia is highly prevalent among breeding squirrel monkeys in Japan. It is likely that the monkeys that are pathogenic Yersinia positive have been inapparently or mildly infected by low pathogenic strains of Yersinia, not highly pathogenic strains of Yersinia, such as YPM-producing Y. pseudotuberculosis. In this review, we will describe the epidemiology of yersiniosis in breeding nonhuman primates in Japan.

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To construct an effective biological control agent for plant root diseases, we isolated Pseudomonas putida strains from the rhizospheres of cucumber plants and used them as hosts of an expression vector for an antipathogenic gene. The antipathogenic gene encoded a chitinase, and was derived from the marine bacterium Alteromonas sp. strain 79401. We screened the genome of P. putida PaW8 to obtain a strong promoter for the expression of this gene. The chitinase expression vector pKAC9-p07, containing the chitinase gene and the promoter from PaW8, was introduced into P. putida strains that could survive well in the rhizosphere. The transformed P. putida strains showed chitinase production and suppressed the damping-off of cucumber seedlings in soils infected with the plant-pathogenic fungus Rhizoctonia solani. This study demonstrates a strategy for the construction of a biological control agent for practical use in the rhizosphere.

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To clarify the presence of a pheromone in Brontispa longissima (Coleoptera: Chrysomelidae), we observed its mating behavior and conducted a series of bioassays. When male and female B. longissima came in contact, the male was observed to hold and mount the female, extend its penis toward her abdominal tip, and copulate. The male was observed to hold the female only after he had touched her with his antennae and/or forelegs. Males showed similar mating attempts toward females killed by freezing. On the other hand, no males showed mating attempts toward females washed with hexane, but they did toward females washed with hexane and re-treated with hexane extract of the female body or female elytra. Furthermore, males showed similar mating attempts toward a glass dummy treated with a solvent extract of female elytra. These results indicate the presence of a female sex pheromone that is perceptible by direct contact and plays an important role in mating in B. longissima. When the crude extract of female elytra was subjected to silica gel chromatography, only the fraction eluted with hexane elicited mating behavior in males. Furthermore, when the active fraction was chromatographed on AgNO₃-impregnated silica gel, only the fraction eluted with hexane elicited mating behavior in males. The contact sex pheromone of B. longissima is therefore believed to consist of one or more less-polar compounds, probably saturated hydrocarbons.

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We studied the effect of aging after the full-open stage on auto-catalytic ethylene production and the expression of genes for ethylene biosynthesis and signaling pathway following exogenous ethylene treatment in long-life carnation flowers (Miracle Rouge [MR] and Miracle Symphony [MS]). As exogenous ethylene treatment time increased, auto-catalytic ethylene production increased in the petals of the control flower (White Sim), MR and MS, on Day 0 and 3, but it increased only slightly in the MR and MS flowers on Day 15. The levels of ethylene biosynthesis pathway gene Dc-ACS1 in MR petals on Day 15 following 20 h exogenous ethylene treatment were around 1/10 of those on Day 3. In MS on Day 15, the levels were around 1/5 of those on Day 3. The levels of another ethylene biosynthesis pathway gene, Dc-ACO1, did not differ on both Day 3 and 15 in MR and MS. Levels of ethylene signaling pathway gene Dc-EIL4 on Day 3 were higher than those on Day 15 at corresponding times. These results indicated that aging may affect the expression of Dc-ACS1 and Dc-EIL4, but not the expression of Dc-ACO1, ethylene receptors, and Dc-EIL1/2, 3.

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The anthelmintic effects of Japanese bead-tree (Melia azedarach var. subtripinnata) leaves and fruits on gastrointestinal nematodes and coccidia in goats were investigated. Fecal samples were taken from three naturally nematode-infected goats and their EPG (eggs per gram) count was analyzed. Another fecal sample was cultured at 25°C for 10 days with water extracts of M. azedarach leaves and fruits separately, and the larvae of the nematodes were counted. The water extracts of leaves and fruits significantly depressed the development of larvae compared to control (water) (P‹0.05). Oral administration of three doses (every three days) of 5 g M. azedarach leaves or 2.5 g fruits/kg BW per day had a significant effect on the reduction of EPG on the 6th and 18th day (P‹0.05), respectively, but not on OPG (oocysts per gram), indicating that leaves have a more rapid effect against nematodes than fruits. However, a blood biochemical profile revealed that liver and renal functions were not affected by doses of M. azedarach leaves or fruits. In conclusion, our results indicate beneficial anthelmintic action from both M. azedarach leaves and fruits against gastrointestinal nematodes, but not against coccidia in goats.

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A survey of antibodies against parapoxvirus species bovine papular stomatitis virus (BPSV) was conducted by agar gel immunodiffusion (AGID) test on 750 serum samples collected from cattle in Ishikawa Prefecture, Japan, in 2007. On farms, 0-21.9% dairy cattle and 8.3-33.3% beef cattle were seropositive, but the difference was not significant. The positive reaction rate was significantly higher in dairy cattle reared on public pastures (33.3-82.4%) than in dairy and beef cattle reared on farms. Among dairy cattle on farms, the positive reaction rate was significantly higher in cattle reared on public pastures and in cattle introduced from other prefectures than in cattle that were neither reared on pastures nor introduced from other prefectures. The same serum samples were tested for antibodies against orf virus (ORFV) by AGID, and the positive reaction rate for ORFV was almost the same or less than that for BPSV, and the immunodiffusion line on the gel was weaker for ORFV. There was no correlation between positive reaction rates in cattle and grazing on public pastures that geographically overlap with the habitat of Japanese serows (Capricornis crispus), which are also hosts of parapoxvirus. These results suggest that the risk of BPSV infection is higher for dairy cattle reared on pastures than on farms, but the risk of infection due to grazing on pastures inhabited by Japanese serows seems to be low.

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