Potato (Solanum tuberosum L.) is among the most important upland crops cultivated for many end uses throughout Japan. Potatoes are consumed in different ways, such as table use, food processing, starch production, and others. At the same time, various cropping systems are adopted according to environmental conditions. Although potato-breeding programs in Japan are conducted by considering these demands, pest and disease resistance is one of the most important traits required for all modern cultivars. There are many pests and diseases affecting potato production in Japan, where conferring resistance against potato cyst nematodes, late blight, common scab, bacterial wilt, and viral diseases has become a main target of breeding. Artificial inoculation tests and cultivation in infested fields were traditionally conducted, in order to evaluate the levels of resistance among breeding materials. However, several DNA markers for pest and disease resistance genes have recently been developed for the selection of resistant genotypes. We have taken both approaches toward the selection of pest and disease resistant genotypes at each breeding step. This review introduces our approaches to develop new pest and disease resistant potato cultivars by using classical and molecular approaches.

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In the last decade, air circulators have been widely used in greenhouses and high tunnels in Japan. The main purpose of air circulation is to provide uniformity in temperature, humidity level, and carbon dioxide concentration in greenhouse air. In addition, empirical knowledge that air circulation prevents hygrophilous diseases increased among growers, together with the inference that air circulation reduces the fuel consumption required for heating. Although the benefits of air circulation remain uncertain, some empirical evidence has been obtained from horticultural and engineering studies in Japan. In this review, the results of these investigations are summarized on the basis of five aspects: performance indicators for circulators, microclimate uniformity, crop yield, suppression of hygrophilous diseases and possible mechanisms. Practical issues regarding the installation of air circulators for greenhouses and high tunnels are also discussed.

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Restoration and reconstruction are the largest and most pressing tasks following the nuclear accident at Fukushima. In this paper we address the task of reducing external exposure to radiation from radioactive material that has accumulated in agricultural land or its peripheral areas, and report on the features of a machine developed to decontaminate the peripheral areas of agricultural embankments and roads, as well as the on-site testing results. Based on the results of analyzing the vertical distribution of radioactive Cs concentration in the soil, we set the removal depth of the machine to 5 cm and proceeded with operation. In terms of usability and the decontamination effects provided by the embankment topsoil removal machine, we achieved a field capacity of 4.4 a/h and reduced the concentration of radioactive Cs and the air dose rate after treatment by about 80%. And based on the test results of the agricultural road surface stripping machine, a field capacity of approximately 0.83 a/h and an extremely high reduction rate of about 90% were achieved after stripping and removal treatment of the soil. Furthermore, the results of surveying the dust exposure status as an operating environment factor related to worker safety (as pertaining to developed machinery) suggested that the fully enclosed construction of the operating section of both machines apparently contributed to reducing the scattering of dirt, sand and dust that degrade the surrounding environment during decontamination operation.

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The production of various rice flour-based food products such as bread, noodles, and cakes is expected to increase the consumption of rice and the utilization of rice paddies in Japan. This paper reviews studies conducted on the characteristics of rice flour and the rice cultivars suitable for the production of rice flour bread containing gluten. The challenges of reducing the cost of producing rice bread are also reviewed. The production of rice flour bread containing gluten of a highly specific loaf volume requires the use of rice flour with a low damaged starch content that can be produced by jet milling wet rice after water or enzyme treatment. The amylose content of rice flour affects the quality of bread, including its shape and hardness. Rice flour with an amylose content of 16% to 20% forms a chewy and moderately soft bread. When rice flour with a low damaged starch content (less than 5%) and a desirable amylose content (16% to 20%) is used, the production of rice flour bread containing gluten is easy without being different from how wheat flour bread is made. In order to reduce the cost of producing rice flour, high-yielding cultivars or a pin milling system using floury rice cultivars should be employed; high-yielding cultivars are now being used for the production of rice flour. With the pin milling system, rice flour belonging to the floury rice cultivar has a low damaged starch content. However, there is a need to develop a high-yield floury rice with reduced weight loss during polishing, as well as new polishing processes. Furthermore, the production of brown rice flour contributes to reducing the cost of producing rice flour because no polishing process is required. Brown rice flour with a low damaged starch content can be produced using a jet mill after soaking for more than 12 h. And given its favorable high nutritional properties, bread made from brown rice flour will prove appealing to consumers. Despite expectations of increasing of the consumption of rice through the use of rice flour as in the production of rice flour bread, the cost reduction of rice flour production and the development of delicious rice flour bread desired by consumers are still insufficient. By understanding the requirements of bread-making companies and obtaining a deeper knowledge about the quality characteristics of rice flour, such as amylose content and protein composition, the production of rice flour bread appealing to consumers can be expected.

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The regulation of ripening in fleshy fruits directly affects the quality and shelf life of such fruit, and extensive research has aimed to understand this regulation based on its agronomic importance. The identification of the key regulatory gene RIN in tomato has opened new horizons in our understanding of fruit ripening. RIN encodes a MADS-box transcription factor that functions as one of the earliest acting factors in the induction of ripening, and the molecular characterization of RIN has helped to elucidate the regulation of fruit ripening. Here I will review current advances in our understanding of the mechanisms that regulate fruit ripening in tomato, including the roles of RIN and other MADS-box proteins, mainly based on our recent studies. First, examination of the molecular properties of the RIN protein revealed that RIN has activities similar to SEPALLATA type MADS-box proteins. Next, identification of the direct transcriptional targets of RIN, via chromatin immunoprecipitation assays, demonstrated that RIN directly regulates a broad range of ripening-associated genes. Finally, identification of MADS-box proteins that interact with RIN revealed the functions of these proteins in ripening regulation. These studies clearly demonstrate the essential roles of MADS-box proteins in the regulation of tomato fruit ripening.

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The structured floral arrangement (SFA) program was developed for cognitive rehabilitation and mental health care. This program required participants to create symmetrical floral arrangements as per predetermined procedures and with instructions given on the sequence of placing each natural material. Attentional deficit, particularly unilateral spatial neglect, nearly disappeared after SFA intervention for a patient with traumatic brain damage. This positive effect was maintained for five months. In schizophrenic patients, visuospatial working memory was improved after SFA intervention. Motivational rehabilitation also increased through the SFA program. This program for mental health care was implemented for participants suffering traumatic stress from the Great East Japan Earthquake of 2011. The number of participants who showed mild physical symptoms (e.g., headache) decreased from seven to just one after SFA intervention. These findings suggest that the SFA program has the potential to improve brain function and/or mental health.

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The nitrate ion content of vegetables has become a human health concern. Accurate and fast tissue (root, stem or leaf stalk) testing in crops is a valuable tool to determine fertilizer needs and maximize fertilizer efficiency. Therefore, the nitrate ion concentrations in fresh vegetable juices were measured using ion-pair ultra performance liquid chromatography (IP-UPLC). The separation was performed on a C18 column with a mobile phase containing 0.15 mM tetrabutylammonium chloride as an ion-pair reagent, 0.1% (w/v) ammonium acetate, and 5% (v/v) methanol at pH 6.2. The chromatogram was detected at 220 nm. The IP-UPLC chromatogram was obtained in 8 minutes, which is 39 minutes less than the time required to obtain a complete ion chromatography (IC) chromatogram of the same sample. The linearity of the method for nitrate ions was high, as evidenced by R² of 0.9996. In nitrate-spiked samples of fresh vegetable juice, the recovery percent consistently approached 100%. Furthermore, the IP-UPLC results obtained without any preliminary sample cleanup were essentially identical to those obtained by IC with a correlation coefficient (R) of 0.999 (n = 10).

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Nipa (Nypa fruticans Wurmb.) is a useful and widely distributed palm in Southeast Asia, but its habitats are declining due to industrial development. Information on genetic diversity, geographical differentiation, and phylogenetic relationships among the populations is important in order to develop conservation strategies for this species. In this study, the genetic diversity within and among 29 natural populations in Peninsular Malaysia was analyzed using the AFLP molecular technique. Polymorphism within a population was detected for 27 populations and three geographically distinct groups of nipa. The results showed that the highest frequency of heterozygosity was found in the west coast southern region, followed by the west coast northern region, and with the lowest frequency in the east coast region. In the phylogenetic tree, the three geographical regions that formed distinct groups with the west coast southern region group were located between the west coast northern region group and the east coast region. These results may suggest that nipa in Peninsular Malaysia has been diffused from or along the west coast southern region to the other regions. The three regional groups are differentiated genetically and it is recommended that all three regions should be targets for the conservation of nipa habitats, in order to reduce genetic erosion within the nipa in Peninsular Malaysia.

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C-type lectin-producing tissue, designated as CLPT, constitutes mouthparts of the flesh fly (Sarcophaga peregrina) and produces a C-type lectin, CLEM 36, which is found to be secreted into saliva. In the present study, CLPT was investigated by immunohistochemical method using a transmission electron microscope (TEM) and scanning electron microscope (SEM), in order to clarify the secretion pathway of CLEM 36. CLPT was found to consist of cells having a microvillus. Each CLPT cell was connected to a fine duct. The fine ducts were bundled together and connected to the food canal. CLEM 36 was densely detected in the microvilli of CLPT cells, and also detected in cytoplasm, and ducts of CLPT. CLPT was found not to be connected to the salivary glands. Since little expression of CLEM genes including CLEM 36 was detected in the thorax and abdomen including the salivary glands in our previous study, when taken together, our current findings suggest that CLPT is a novel secretory gland which is independent of salivary glands, and has its own role in the intake of foods.

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China’s maize productivity and fertilizer consumption both have significant impact on global markets, and must be clarified through macro-level studies of Chinese maize yields. As such, this study used a crop response model to estimate the effects of fertilizer nutrients, seed input per unit area, and climate factors on maize yield. The results suggest that phosphorus and potassium inputs significantly affect maize yield, especially in major maize-producing areas. This study also confirmed the relationship between lower seed input per unit area and a higher yield.

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The aim of this study was to provide data on the prevalence of serovars of 48 strains of Actinobacillus pleuropneumoniae isolated in Japan from 2006 to 2011, and their antimicrobial resistance profiles (ARPs) by using the disc diffusion method. Of the 48 strains, 10.4% were serovar 1, 60.4% were serovar 2, 14.6% were serovar 5, and 2.1%, 2.1%, 2.1%, and 8.3% were serovars 6, 7, 12, and 15,respectively. We found that 25.0%, 12.5%, 39.6%, 37.5%, 18.8%, and 0% of the strains were resistant to penicillin G, ampicillin, oxytetracycline (OTC), sulfisoxazole, chloramphenicol, and norfloxacin,respectively. The ARPs of each serovar differed, with serovar 1 strains exhibiting multi-antimicrobial resistance to more than three antimicrobials. In contrast, 44.8% of the serovar 2 strains exhibited no resistance, and 34.5% were resistant to only one antimicrobial. All serovar 1, 5, and 15 strains were resistant to OTC, whereas serovar 2 exhibited lower resistance to OTC (6.9%). No significant increase in the prevalence of resistance to these antimicrobials was observed during the last half decade in Japan when compared with published data on the prevalence of resistant strains of A. pleuropneumoniae collected from 1989 to 2005. Regarding the prevalence of serovars, there has been a recent increase in the isolated cases of serovar 15.

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