Showing papers in "Jarq-japan Agricultural Research Quarterly in 2016"

Decline in fertility of paddy soils induced by paddy rice and upland soybean rotation, and measures against the decline.

Abstract: Crop rotation between irrigated paddy rice (Oryza sativa L.) and upland soybean [Glycine max (L.) Merr.] (paddy-upland rotation) induces a decline in soil nitrogen (N) fertility, as observed by available soil N. There was a significant negative correlation between the available soil N and the proportion of upland seasons to total crop seasons after the initiation of paddy-upland rotation (upland frequency). The decline in soil N fertility was alleviated by the application of organic materials. Soil total carbon also tended to decrease with an increase in upland frequency. Soil physical properties were affected by the paddy-upland rotation. As soil organic matter decomposed in paddy-upland rotation, the soil density increased with decreasing soil porosity. A suitable range of available soil N for paddy-upland rotation was identified between 80 and 200 mg/kg, the same as for paddy rice. The keys to controlling soil N fertility in paddy-upland rotations are the upland frequency and application of organic materials. To sustain the available soil N over the minimum suitable level of 80 mg/kg, the upland frequency should not exceed approximately 60% when only crop residues and no other organic materials are applied. The upland frequency can be increased by the repeated application of organic materials, thereby maintaining a higher level of available soil N.

Controlled Environment Agriculture for Effective Plant Production Systems in a Semiarid Greenhouse

Abstract: of water, respectively. The air relative humidity for fog cooling was slightly higher than that for pad-and-fan cooling, at approximately 35%. An English version of Visual VETH (ventilation-evapotranspiration-temperature-humidity) software was also developed. A cooling strategy devised for semiarid greenhouses found that the air relative humidity inside a greenhouse decreased with an increase in ventilation rate as expected from simulation based on steady-state energy balance equations, while the water use for fog cooling increased. A simple and unique control algorithm for fogging and ventilation inlet openings demonstrated the possibility of maintaining relative humidity and air temperature simultaneously within a desirable range while reducing the water use for fog cooling. The tomato plant canopy transpiration rate and the water balance relative to the natural ventilation rate in a fog-cooled greenhouse were also investigated. The transpiration rate increased linearly with an increase in vapor pressure deficit (VPD) of the air. At a lower ventilation rate made possible by reducing the ventilation inlet openings, total water use in the greenhouse decreased by 13% and relative humidity increased as was expected from the steady-state energy balance simulation. The decrease in canopy transpiration resulted from the decrease in VPD, and was at a magnitude greater than that of the fog evaporation rate under similar experimental conditions with relatively high humidity in the range of 70-94%. By optimizing the natural ventilation rate, the greenhouse could be effectively cooled with less water use. Arizona can be considered a model analogous to many other semiarid climate conditions. Due to the long history of greenhouse technology development, the application of greenhouse crop production to an area with excessive radiation and dry air remains a relatively new effort. We believe that our efforts will contribute not only to the American Southwest but also to enhancing the application of greenhouse technology for crop production in these climate regions worldwide, including Mexico, China, the Middle East and Africa.

Characteristics of Rice Flour Suitable for the Production of Rice Flour Bread Containing Gluten and Methods of Reducing the Cost of Producing Rice Flour

Abstract: 3 Niigata Agricultural Research Institute Food Research Center (Kamo, Niigata 959-1381, Japan) Abstractproduction of various rice flour-based food products such as bread, noodles, and cakes is expect- ed 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 con- tributes 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 produc- tion 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 produc- tion of rice flour bread appealing to consumers can be expected.

Regulation of Tomato Fruit Ripening by MADS-Box Transcription Factors

Abstract: 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 MADSbox 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. Discipline: Horticulture Additional key words: FRUITFULL(FUL), ripening inhibitor (rin), TAGL1 *Corresponding author: e-mail yasuito@affrc.go.jp Recieved 6 January 2015; accepted 25 May 2015. 05_ItoY_p033-038.indd 33 2015/11/26 21:13:38 34 JARQ 50 (1) 2016 Y. Ito RIN functions as a SEPALLATA-type MADSbox transcription factor In flowering plants, MADS-box transcription factors play important roles in the control of plant growth and development, including vegetative growth, flowering, floral organ development, seed development, senescence, fruit ripening, and organ abscission (Smaczniak et al. 2012). Extensive investigation of the determination of floral organ identity by MADS-box transcription factors produced the ABC model (Coen & Meyerowitz 1991), and then the quartet model, which explains that tetramers with various combinations of four MADS-box proteins determine the identity of the four whorls of floral organs, sepal, petals, stamens, and carpels (Theissen & Saedler 2001). In this model, the E-class SEPALLATA MADS-box proteins (SEPs) form tetramers with other MADS-box proteins and also confer transcription-activating activity to the complex (Honma & Goto 2001, Immink et al. 2002). RIN is a tomato homolog of SEP; thus, we characterized the molecular activities of RIN in comparison with SEPs (Ito et al. 2008). MADS-box transcription factors bind a specific C-(A/T)-rich-G (CArG) motif (de Folter & Angenent 2006). To identify the DNA sequences bound by RIN, we conducted a DNA-binding site selection experiment. From a random, double-stranded oligonucleotide pool, we selected RIN-binding DNA fragments and determined the consensus sequence of the selected sequences as (T/a)(T/a)DCCA(A/T)(A/t)(A/T)ATAGHAA (bold letters indicate the CArG motif, uppercase and lowercase letters represent the most frequent and relatively more frequent nucleotide, respectively, and D and H represent A/T/G and A/T/C, respectively). The consensus sequence is a typical CArG sequence with strong similarity to the consensus DNA binding sites of the SEP proteins (Huang et al. 1996, Huang et al. 1995). Several MADSbox proteins, including the SEP proteins, can activate transcription. RIN also has the transcriptional activation activity, which requires the C-terminal domain of the RIN protein (Ito et al. 2008). The rin mutants have a genomic deletion that includes the last exon of RIN and a part of the cis-acting regulatory region of the neighboring gene, MACROCALYX (MC), which encodes a MADS-box transcription factor that regulates sepal size and the development of pedicel abscission zones (Nakano et al. 2012, Vrebalov et al. 2002). In the rin mutants, transcription of the locus produces a chimeric RIN-MC mRNA that lacks the last exon of RIN and the first exon of MC (Giovannoni 2004, Kitagawa et al. 2005, Vrebalov et al. 2002). The chimeric mRNAs are translated and the mutant proteins accumulate in the fruit cells (Ito et al. 2008, Martel et al. 2011, Qin et al. 2012). The mutant proteins retain DNA-binding activity, but lack transcriptional activation activity, which requires a domain encoded by the last exon of RIN. These results suggested that RIN is a DNA-binding protein that confers transcriptional activation activity to a MADS-box transcription factor complex that functions during ripening. Also, the rin mutation removes the transcriptional activation activity from the protein, thereby preventing the up-regulation of genes required for ripening (Ito et al. 2008). Ripening-associated genes directly regulated by RIN At the onset of ripening, numerous genes for divergent ripening-associated processes become upor down-regulated in a highly synchronized manner. Most of these transcriptional changes do not occur in the rin mutants, implying that RIN has essential functions in this massive regulatory shift. However, how RIN regulates the divergent pathways remains unclear. To specify the roles of RIN, several groups used chromatin immunoprecipitation (ChIP) assays to identify the direct target genes of RIN. ChIP uses antibodies specific for the protein of interest to collect target DNA sequences of that protein as protein-DNA complexes (chromatin), and this assay has been used to ascertain the interactions of transcription factors with DNA in vivo (Hecht & Grunstein 1999). The ChIP assays for RIN targets first identified LeACS2, which encodes a 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS), a rate-limiting enzyme for ethylene biosynthesis, and is responsible for ripening-associated ethylene production (Barry et al. 2000, Ito et al. 2008). The expression of LeACS2 is strictly up-regulated in a RIN-dependent manner (Barry et al. 2000). A ChIP assay on ripening fruits with RIN-specific antibodies detected RIN binding to CArG motifs in the LeACS2 promoter (Fujisawa et al. 2011, Ito et al. 2008). The results identify Fig. 1. RNAi-mediated suppression of FUL1 and FUL2 inhibited tomato fruit ripening 05_ItoY_p033-038.indd 34 2015/11/26 21:13:38 35 MADS-Box Transcription Factors Regulating Tomato Fruit Ripening LeACS2 as a direct target of RIN and strongly suggest that RIN activates LeACS2 transcription during ripening. In a similar manner, ChIP assays with RIN-specific antibodies were conducted to examine RIN binding to the promoters of genes involved in the major pathways associated with well-studied ripening phenomena (Fujisawa et al. 2011, Martel et al. 2011). Transcriptome and proteome approaches were also used to screen candidate RIN targets, and the candidates expressed in a RIN-dependent manner were examined by ChIP assays (Fujisawa et al. 2012, Qin et al. 2012). The assays detected the direct binding of RIN to many candidate genes, such as those involved in ethylene synthesis and signaling (LeACS2, LeACS4, E8, and NR), carotenoid biosynthesis (PSY1), aroma compound generation (TomloxC and ADH2), cell wall metabolism (LeEXP1, LeMAN4, PG, Cel2, and TBG4), and transcription factors (NOR, CNR, TDR4, HB1, and RIN), indicating that RIN induces many different ripening-associated events via direct transcriptional regulation of the multiple genes involved in these events. Of the genes examined in the ChIP assays with the RIN antibodies as described above, most were identified as direct targets of RIN. These results suggest that RIN may target many genes required for ripening-associated physiological changes. To understand the roles of RIN during ripening more comprehensively, a large-scale experiment to identify RIN targets was conducted using ChIP coupled with DNA microarray analysis (ChIP-chip). First, RIN-binding DNA fragments from ripening tomato fruits were recovered by ChIP with the RIN antibodies. The recovered fragments were hybridized to a DNA microarray carrying probes designed for putative promoters (2-kb upstream regions from translation initiation sites) for all of the 35,802 predicted genes in the tomato genome. This experiment identified more than 1,000 RIN-bound regions throughout the genome (Fujisawa et al. 2013). Of the genes around the binding sites, those that were upor down-regulated in a RIN-dependent manner were identified as the direct targets of RIN. This analysis identified more than 200 genes as either positive or negative targets of RIN. The direct targets function in more than 60 biological pathways, including metabolic pathways such as ethylene, carotenoids, lipids, sugars, and amino acids, and various biological activities such as subcellular localization, chlorophyll degradation, stress responses, transcriptional regulation, and other activities (Fujisawa et al. 2013). The direct targets of RIN were also identified by ChIP followed by sequencing (ChIP-Seq) (Zhong et al. 2013). These results indicate that RIN functions via direct transcriptional regulation in a wider range of fruit ripening processes than previously assumed. FRUITFULL homologs and TAGL1 form complexes with RIN and regulate ripening As a MADS-box protein, RIN likely interacts with other MADS-box proteins, which should regulate ripening in a manner similar to RIN. Indeed, a yeast two-hybrid screen of a cDNA library from ripening fruits identified two MADS-box proteins associated with RIN (Shima et al. 2013). Both proteins showed high sequence similarity to Arabidopsis thaliana FRUITFULL, which is required for the proper development of fruits and cauline leaves (Gu et al. 1998) and functions in development of the pod dehiscence zone (Ferrandiz et al. 2000). The tomato homologs (FUL1 and FUL2) have high sequence similarity to each other, but showed distinct expression patterns. Expression of FUL1 increased strongly at the on

Recent Progress in Molecular Studies on Storage Root Formation in Sweetpotato (Ipomoea batatas)

Abstract: Elucidating the mechanisms underlying the formation of storage roots is important for further improvement of sweetpotato. Although the process of storage root formation in sweetpotato has been extensively studied anatomically and physiologically, the genetic and molecular mechanisms remain largely unknown. Recently, extensive gene expression analysis has identified numerous genes differentially expressed between fibrous and storage roots. The results of these analyses agreed with previous anatomical and physiological observations in that genes related to starch and storage protein biosynthesis were up-regulated, and those related to lignin biosynthesis were down-regulated in the storage roots. Also, molecular biological studies and analyses using transgenic sweetpotato plants have suggested that an expansin protein and several transcription factor genes, such as a Dof-type zinc finger protein, MADS-box proteins, and KNOXI proteins, are involved in the characteristic physiological process of storage root formation. Furthermore, ongoing whole-genome sequencing of sweetpotato and the related Ipomoea species is expected to identify genetic differences related to storage root formation. Although these studies are valuable as a first step in elucidating the critical genes and genetic network that control the formation of storage roots, further physiological, genetic, and molecular biological studies are needed to reveal the entire molecular process. Discipline: Biotechnology Additional key words: tuberous root, development, gene *Corresponding author: e-mail mtanaka@affrc.go.jp Received 27 April 2015; accepted 12 January 2016. Introduction Sweetpotato (Ipomoea batatas) is an important food crop with global production totaling about 100 million tonnes (FAO 2013), and shows the highest daily energy yield per hectare among the major food crops available in developing countries (Woolfe 1992). Although sweetpotato originated in the tropical Americas, about 80% of its worldwide production now comes from Asian countries. Rich in vitamins and minerals, and also containing a large amount of starch, the storage roots of sweetpotato are an important source of nutrition, especially in developing countries (Woolfe 1992). In addition to table use, sweetpotato is utilized as an important raw material for food processing and industrial purposes, such as starch and pigment production. Given its outstanding calorie productivity and relatively high tolerance to unfavorable weather and cultivation conditions, sweetpotato is expected to become a candidate crop for feeding the world’s growing population, but its world average yield peaked in the 1990s and has not increased since (FAO 2013). To overcome the yield plateau for this important crop, the physiological and genetic basis of sweetpotato productivity should be clarified. The storage roots of sweetpotato are formed by a secondary thickening of adventitious roots formed on the underground nodes of transplanted stem cuttings. These storage roots accumulate photosynthetic products as a sink organ throughout the cultivation period of sweetpotato. This long duration of dry matter being accumulated in the storage roots is a major reason for the high and stable productivity of sweetpotato (Tsuno and Fujise 1965). Grafting experiments using various sweetpotato cultivars and wild-relative plants (I. trifida) have also suggested that the dry matter productivity of sweetpotato is highly dependent on the sink potential of developing storage roots (Hozyo & Park 1971, Hahn 1977, Nakatani et al. 1988). Furthermore, Kokubu (1973) suggested that the level of starch accumulated in storage roots is related to their anatomical structure.

The Relationship between SPAD Values and Leaf Blade Chlorophyll Content throughout the Rice Development Cycle

Abstract: The Soil and Plant Analyzer Development (SPAD) meter is a chlorophyll meter used worldwide due to its convenience. The present study was conducted to investigate the relationship between SPAD values and rice leaf blade chlorophyll content throughout the entire rice development cycle, and determine whether it is possible to apply a nonlinear model to the relationship. A field experiment was conducted in which the rice communities of two cultivars (‘Nipponbare’ in 2000 and ‘Kinuhikari’ in 2002) with wide-ranging chlorophyll content were generated by varying nitrogen fertilizer rates. Data sets comprising SPAD values for leaves sampled from the various rice communities and actual chlorophyll content of the same leaf measured spectroscopically were created. A linear model for each cultivar was applied to the relationship between the SPAD value and chlorophyll content of the same leaf at each developmental stage. Their relationship revealed a good fit. Subsequently, linear and nonlinear models were applied to the data through all rice development stages of each cultivar. A nonlinear model for each cultivar revealed a better fit to the relationship between SPAD values and rice blade chlorophyll content than the linear model. The following nonlinear models were then generated to fit the data: ChlNi = 0.965 exp (0.036 Sp) − 1 (r2 = 0.93) ChlKi = 0.925 exp (0.038 Sp) − 1 (r2 = 0.94) where, ChlNi and ChlKi denote the leaf blade chlorophyll content (mg/g, flesh weight) for Nipponbare and Kinuhikari, respectively, and Sp is the SPAD value. The coefficients of the nonlinear models obtained for each cultivar were very similar. The possibility of applying a nonlinear model to the relationship between the SPAD value and rice leaf blade chlorophyll content was confirmed with high coefficients of determination. To establish a broadly applicable calibration equation based on a nonlinear model for evaluating the chlorophyll content in the rice leaf blade using a SPAD meter, more studies are needed using various cultivation data sets. Discipline: Crop production Additional key words: nonlinear model, nitrogen fertilizer, top dressing Present address: National Agriculture and Food Research Organization (NARO) Kyushu Okinawa Agricultural Research Center (Koshi, Kumamoto 861-1192, Japan) *Corresponding author: e-mail waki@affrc.go.jp Received 26 May 2014; accepted 12 January 2016. Introduction The chlorophyll or nitrogen content in crop leaves is important information for managing the nitrogen status and monitoring the physiological activity of crops. The Soil and Plant Analyzer Development (SPAD) meter is a simple, convenient, portable and nondestructive chlorophyll meter used worldwide to manage crop nitrogen status and monitor crop activity. Many studies have used SPAD meters to diagnose crop nutritional status (Furuya 1987, Bullock and Anderson 1998, Lopez-Bellido et al. 2004, Wu et al. 2007, Asai et al. 2009) or photosynthetic activity (Inoue 1987). However, SPAD meters only provide researchers with a measure of relative leaf chlorophyll or nitrogen content. In order to determine the absolute leaf chlorophyll or nitrogen content based on SPAD values, the relationship between SPAD values and actual leaf chlorophyll or nitrogen content

Phylloplane Fungal Enzyme Accelerate Decomposition of Biodegradable Plastic Film in Agricultural Settings

Abstract: The rate at which biodegradable plastic (BP) mulch films decompose in agricultural fields depends on environmental conditions. If degradation of used mulch film is insufficient for plowingdown, they impede agricultural work and get entangled in farm equipment. We developed a new technique to accelerate the degradation of BP mulch films in agricultural fields by applying an enzyme from a Paraphoma-like phylloplane fungus (strain B47-9). Spray treatment of the enzyme solution alone significantly accelerated film degradation, and the additional application of a moistureretaining agent, carboxymethyl cellulose sodium salt (CMC), further accelerated decomposition. Commercially available BP mulch films started to break down one day after treatment with the enzyme solution and CMC. Within seven days of treatment, small tears in the film turned into long cracks, covering 6.2% of the total film area. Discipline: Agricultural environment Additional key words: biodegradable mulch film, accelerated degradation, moisture-retaining agent

DNA Marker-Assisted Selection Approach for Developing Flooding-Tolerant Maize

Abstract: Flooding due to worldwide climate change can drastically affect crop production. To overcome the detrimental effects of f looding during maize growth, we have been developing f looding-tolerant maize via DNA marker-assisted selection using a flooding-tolerant teosinte, Zea nicaraguensis, as a donor parent. Over the last decade, quantitative trait locus (QTL) information on flooding-tolerancerelated traits in Zea species has been obtained at the NARO Institute of Livestock and Grassland Science, and near-isogenic lines containing one or more QTLs have been developed for several flooding-tolerance-related traits, such as the capacity to form constitutive aerenchyma, tolerance to flooding under reducing soil conditions, and ability to form adventitious roots at the soil surface. In field trials, we have been accumulating data demonstrating the effectiveness of teosinte-derived QTLs on flooding tolerance, and are preparing to release a flooding-tolerant F1 maize hybrid within a few years. In addition, we have just started a project to clone Qft-rd4.07-4.11 by using next-generation sequencing, which would make it possible to extend the use of this QTL to other upland crops. Discipline: Plant breeding Additional key words: aerenchyma, QTL, reducing soil conditions, waterlogging, wild Zea

Digital Filters to Eliminate or Separate Tidal Components in Groundwater Observation Time-Series Data

Abstract: This paper discusses digital low-pass filters for application to tidally fluctuated groundwater observation data. Three types of filters that are commonly used, mainly for oceanography, and newly produced filters are comparatively evaluated with a focus on their ability to eliminate major diurnal and semidiurnal tidal components. All the digital filters presented are the nonrecursive type that can easily be used with spreadsheet software. Newly produced low-pass filters are excellent tide-killer filters with a length of 241 hours applicable to hourly sampled time-series data. The new filters suppress eight major diurnal and semidiurnal tides to practically negligible magnitudes (10 order input), with longer-period components (longer than two days) being nearly completely preserved. High-pass filters transformed from these new tide-killer low-pass filters can separate the components of semidiurnal to diurnal tidal periods from other longer-period components, keeping approximately the same magnitude as in the input data for eight major tides. Therefore, the use of the new high-pass filters prior to quantitative analysis of major tidal components in groundwater observation data should effectively improve the accuracy of analysis. Discipline: Agricultural engineering Additional key words: comparative study, nonrecursive filter, tidal filter, low-pass filter, high-pass filter

Breeding of Pest and Disease Resistant Potato Cultivars in Japan by Using Classical and Molecular Approaches

Abstract: 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 consider- ing 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 breed- ing 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.

Body Surface Temperature of Suckling Piglets Measured by Infrared Thermography and Its Association with Body Weight Change

Abstract: The aim of this study was to quantify the body surface temperature of suckling piglets, and determine the association between body surface temperature, body weight and growth rate during the suckling period. The study population consisted of 72 piglets from six sows that were randomly selected at day 4 after farrowing. Infrared thermography and weighing were performed every other day from day 4 to 24 of lactation. Thermal images of each piglet were taken at the eye, base of ear, back, and anus using a handheld infrared camera. Body surface temperature was associated with piglet age and growth rate (P < 0.05), but not with body weight. At day 14, the body surface temperature was highest in all regions (P < 0.05), while at day 24 the piglets averaged lower body surface temperatures than at days 4-18 (P < 0.05). The interaction between piglet age and growth rate significantly affected body surface temperature (P < 0.05). The body surface temperature only varied with growth rate in piglets 12 and 14 days old after birth (P < 0.05). In conclusion, infrared thermography might be useful for the detection of body surface temperature that can be used as an indication of growth performance in piglets with health problems. Discipline: Animal industry Additional key words: Birth weight, early diagnosis, sow, weaning weight *Corresponding author: e-mail a0d802u@cc.miyazaki-u.ac.jp Received 6 July 2015; accepted 13 January 2016. Introduction Low piglet weight at weaning is associated with a high mortality rate during growth periods and results in a loss of income for the farmer (Tanaka & Koketsu 2008). Thus, it is important for producers to identify piglets with low growth rates early in the suckling period, in order to provide treatment and prevent mortality. Under field conditions, however, it is difficult to measure piglet body weights daily during the suckling period due to the rapid movements of these animals and large size of the farrowing crate, which make it difficult to pick up the piglets. In addition, the frequent restraint and handling of suckling piglets is both labor-intensive and detrimental to their well-being (Chung et al. 2010). Infrared thermography is a non-invasive technique that permits the recording of body temperature without having touch the animal (Stewart et al. 2008). Body temperature is a fundamental parameter in assessing an animal’s health condition (Chung et al. 2010). Thus, a body surface temperature measured by infrared thermography could be useful for the detection of piglets with retarded growth or disease. In pigs, hypothermia is a major cause of neonatal piglet mortality and predisposes piglets to mortality by

Non-farmers’ Preference for Assisting with Farm Tasks as a Method of Health Promotion

Abstract: Increasing attention has been focused on promoting the physical and psychological health of non-farmers through farm activities such as home gardening and allotment gardening. In addition to these two farm activities, another farm activity — assisting with farm tasks — has been recently observed among non-farmers. Assuming that certain activities promote the health of non-farmers, specifically assisting with farm tasks near the home, allotment gardening, home gardening, walking, hiking, light physical exercise, home training with gymnastic equipment, and bowling, the preference for assisting with farm tasks compared to other farm and non-farm activities for health promotion was assessed among nonfarmers in Chiba prefecture, Japan. Based on the best-worst scaling approach, assisting with farm tasks and allotment gardening were found to be the least and second-least preferred activities, respectively, while home gardening was found to be more preferred than these two farm activities. According to our results, decreasing farm task difficulty, reducing the travel cost of visiting a farmer, and asking non-farmers to only assist with tasks that can be conducted at their own pace could increase the nonfarmers’ preference for assisting with farm tasks as a method of health promotion.

A Method for High-Quality Citrus Production Using Drip Fertigation and Plastic Sheet Mulching

Abstract: A novel cultivation method that aims to produce high-quality satsuma mandarin (Citrus unshiu Marc.) fruit and other types of citrus fruits was proposed in 2000, in order to meet the market demand for high-quality fruits (i.e., fruits with high sugar content and moderate acidity); this method is called the marudori method. The main feature of this method is the combined drip fertigation with conventional plastic sheet mulching, both of which control tree moisture. Tree moisture management is crucial for the production of high-quality citrus, particularly satsuma mandarins. Therefore, proper active moisture control techniques are required in Japan, where precipitation may vary considerably. Sheet mulching is a conventional technique in which trees are subjected to water stress, which increases the sugar content of fruits. Additionally, drip fertigation is a technique for effective watering and fertilizing, but not commonly used in citrus cultivation in Japan. The combination of these techniques allows this method to provide such benefits as improved fruit quality, efficient fertilization, and enhanced growth of young trees, among others. In this review, we describe this method in detail and discuss the challenges encountered during the improvement and enhancement of the marudori method, with the aim of establishing an objective cultivation system integrated with ICT and other scientific techniques. Discipline: irrigation, drainage and reclamation; horticulture Additional key words: drip irrigation, fruit quality, marudori method, moisture control, satsuma mandarin *Corresponding author: e-mail shima@affrc.go.jp Received 11 May 2015; accepted 7 January 2016. Introduction 1. Importance of tree moisture management in citrus cultivation Citrus is one of the most important crops in fruit cultivation in Japan. While many different types of citrus fruits are cultivated, satsuma mandarin (Citrus unshiu Marc.) has been the predominant fruit cultivated in Japan for many years. The production of high-quality fruits, including citrus fruits, has become critical in the Japanese fruit market. This is because the demand for high-quality fruits has been growing along with the continuing diversification of consumer needs. Moreover, there has been growing demand for the export of high-quality fruits. High-quality citrus fruits are generally defined as those having a high sugar content and moderate acidity. The history of tree moisture during the growth stage strongly affects the quality of mature citrus fruits. Water stress during the growth stage of fruit increases both sugar content and acidity. Notably, trees should be maintained under moderate water stress during certain periods in the summer and autumn, e.g., from late August to early December (Yakushiji et al. 1996). In conventional outdoor citrus cultivation, however, tree moisture is roughly controlled with rain-fed or sprinkler irrigation systems. Thus, in order to produce high-quality citrus fruits, tree moisture management techniques are critical. 2. Instability of precipitation in Japan Japan’s annual precipitation falls within the range of 1000 to 2000 mm, or about twice the world average. However, short-term fluctuations in precipitation are considerably large. For example, while there may be 200 days without rainfall, over 100 mm of rain may fall in one day during an average year in Tokyo. There are two climate factors affecting heavy precipitation in Japan. One is the

Development and Adaptability of Individual Packaging Containers for Strawberries

Abstract: We have previously reported on the design of individual packaging containers for strawberries to prevent the degradation of quality. The container is bivalve-shaped and the two “shells” of the bivalve grip the peduncle of the fruit, thereby allowing packaging without the fruit coming into contact with the packaging material. We observed that the rate of weight loss and the extent of damage were lower for strawberries packed in individual containers than for strawberries packed in conventional packages. Thus, these containers preserve the quality of strawberries more efficiently (Konya et al. 2015). This review reports on the development of a practical-type container with improved shape and material. We measured the container’s basic performance, such as temperature following capability and peduncle grip force, and also conducted vibration and dropping tests to examine its practical utility. As a result, we observed that the practical-type container is resistant to vibration during transport, but vulnerable to dropping when the peduncle is positioned at the top. Thus, in case of long haul or transshipment transportation, the peduncle should be positioned at the bottom. Discipline: Postharvest technology Additional key words: damage, grip, peduncle, quality

Structured Floral Arrangement Program Developed for Cognitive Rehabilitation and Mental Health Care

Abstract: 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 natu- ral 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 interven- tion. 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 pro- gram has the potential to improve brain function and/or mental health.

Current usage of air circulators in greenhouses in Japan.

Abstract: 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. Discipline: Agricultural Engineering Additional key words: protected horticulture, microclimate, pest management *Corresponding author: e-mail tkuro@affrc.go.jp Received 11 November 2014; accepted 27 May 2015. 02_Kuroyanagi_p007_012.indd 7 2015/11/26 21:12:22 8 JARQ 50 (1) 2016 T. Kuroyanagi of air circulation on the microclimate and crop health in greenhouses and high tunnels. Performance indicator Various types of air circulators are available in Japan, and the differences among the products are based on their size, design, and performance. Such aspects of performance as airflow rate and coverage are generally specified. However, there is no standard procedure, even for measurement of the airflow rate of air circulators. The airflow rate of some domestic products is measured based on the JIS C 9601 standard (1990), whereas that of others is measured in accordance with ANSI/AMCA 230-99 (2000). The procedure under the JIS standard is based on the measurement of horizontal distribution of air velocity at three times the distance of the fan diameter from the outlet, whereas the procedure under ANSI/AMCA 23099 is based on the measurement of thrust and ambient air density, and the impeller’s physical diameter. Therefore, a comparison of commercial air circulators based on the airflow rates listed in the specifications is inadequate. The air circulation coverage of six commercial fans was previously investigated using an identical protocol (Kuroyanagi 2013a). Airflow created by each fan was measured in a closed and empty garage (8.5 m in width, 33.6 m in depth, and 6.1 m in height). A 6 m × 25 m horizontal grid pattern with 1-m spacing was marked on the floor, and air velocities were measured at each intersection using four hot-wire anemometers at heights of 0.5 m, 1.0 m, 1.5 m, and 3.0 m; that is, air velocities were measured at 728 points for one circulator. The results showed that the percentage of measurement points varied among the circulators in a 6 × 25 m grid where the airflow generated by each circulator was observed. For data analysis, the range of air circulation was defined as the percentage of points where the measured air velocity was greater than 0.2 m s-1. The power consumption correlated significantly with the range of air circulation observed (R = 0.84, P < 0.05), but the airflow rate listed in the specifications was not (R = 0.36, N.S.). It has thus been concluded that power consumption is a valid evaluation indicator for the performance of air circulators, although highly inefficient circulators are hardly distinguishable. Uniform air temperature and humidity The spatial gradient of air temperature in greenhouses affects the uniformity of crop growth. An investigation in a greenhouse with a 1.3 ha cultivation area showed that the stems of tomatoes became thicker and shorter in the area with a lower air temperature (Takayama et al. 2014). Uneven growth is undesirable for not only the yield but also for crop management such as training or artificial pollination. In particular, protected horticulture in Japan largely depends on small-scale greenhouses and high tunnels, which often generate a gradient of air temperature between the center and alongside the walls or ceiling in all seasons. Therefore, the effect of air circulators on the uniformity of air temperature has been confirmed in small-scale greenhouses and high tunnels. The effect of air circulation on the distribution of wind speed and air/leaf temperature in the daytime and in the heating hours at night was investigated for a double span greenhouse (Ishii et al. 2012). The greenhouse (14.4 m in width, 60.0 m in length, 4.2 m in height) was separated by plastic film into four compartments (7.2 m × 29 m). The circulators used in the study were axial fans (AB353a, Fulta Electric Machinery, Co., Ltd.; airflow rate of 79 m3 min-1) that provided horizontal airflow. Forced air heating (GPN25M, Fulta Ennetsu, Co., Ltd.; heating capacity of 53.4 kW, unknown airflow rate) was applied using a plastic film duct. The circulators were positioned at a height of 2.1 m for the compartment where tomatoes were cultivated (crop height of 1.8 m). During the daytime in winter, at least two circulators were necessary to provide a wind speed of at least 0.5 m s-1 above the crop, and at least 0.3 m s-1 in the crop canopy. The arrangement of circulators provided uniform air temperature with a standard deviation of 0.6°C or less, whereas the deviation was ca. 1.1°C without air circulation. The authors suggested that the effect of air circulation on leaf temperature was negligible because solar radiation had a greater impact on leaf temperature. During the heating hours, operation of the circulator decreased the standard deviation of air and leaf temperature at 1.5°C or less, whereas the standard deviation was 2.5°C and more without air circulation. The effect of air circulation on the hygrothermal conditions was investigated for single-span high tunnels (Matsuura et al. 2004). Two high tunnels used in that study were of identical size (6 m in width, 15 m in length, 3.6 m in height) relative to the heating equipment. One high tunnel was equipped with an air circulator 2 m from the end panel at a height of 2.2 m. The type of circulator used in that study was an axial fan (280B, Vornado Air LLC; unknown airflow rate) that provided horizontal airflow. Forced air heaters (KA-321, Nepon Inc.; heating capacity of 37.2 kW; airflow rate of 60 m3 min-1) with plastic film ducts were used. The heaters maintained air temperature in the high tunnel at higher than 12°C. Non-grafted tomato seedlings (Solanum lycopersicum, cv. House Momotaro, Takii Co., Ltd.) were transplanted into fertilized soil (N:P:K = 2.0, 1.7, 2.0 kg a-1) on November 2, 2001 and cultivated until June 2002 when the 02_Kuroyanagi_p007_012.indd 8 2015/11/26 21:12:22 9 Current Usage of Air Circulators in Greenhouses in Japan fruit reached the 11th truss. The plant density was ca. 1.5 plant m-2. The circulator created a wind speed of 0.5-1.3 m s-1 above the canopy, and 0.1-0.2 m s-1 in the canopy, whereas calm conditions were observed in the high tunnel without the use of any air circulators. Air circulation decreased the vertical air temperature gradient between inside and above the canopy, with values of 2.8°C for the control tunnel and 0.8°C on average for the high tunnel with the fan from January to February of 2001. A decrease in the vertical gradient of relative humidity was also observed, from 3.6% for the control tunnel to 0.1% for the high tunnel with the fan. The authors did not discuss the reason why horizontal airflow reduced the vertical gradient of air temperature and relative humidity. It could be explained by a circulation of airflow along the gable end wall of the high tunnel because airflow from a commercial air circulator reaches 20 m and more ahead (Kuroyanagi 2013a). Yield and photosynthesis Matsuura et al. (2004) also reported that air circulation significantly increased the yield in January from 369 g m-2 for the control tunnel to 622 g m-2 for the tunnel with the fan (P = 0.0047). In contrast, the total yield was 9.1 kg m-2 for the control tunnel and 9.3 kg m-2 for the high tunnel with the fan. There was no significant difference between both tunnels for the total yield (P = 0.9892) and unmarketable yield (P = 0.7353). Matsuura et al. (2004) suggested that the increased yield at an early period resulted from higher temperature within the canopy for the high tunnel with air circulation. Their assumption is supported by the dependence of progress of an initiated fruit towards ripeness on temperature (Heuvelink 2005). On the other hand, the increase in yield might be related to the enhanced gross photosynthesis of leaves due to the supply of airflow around 0.5 m s-1 (Yabuki & Miyagawa 1970). Shibuya et al. (2006) confirmed that the relationship between the enhancement of photosynthesis and the airflow supply for tomato seedlings that were raised at ambient carbon dioxide (CO2) concentration, whereas air circulation did not change the total dry matter production and cumulative fruit growth for mature tomatoes raised at an elevated CO2 concentration. (Elings et al. 2007). Therefore, the increased yield at an early period in Matsuura et al. (2004) might be mainly attributable to the rise in air temperature around the first truss of tomatoes. Further studies should be conducted to deepen understanding of the relationship among air circulation, canopy photosynthesis, and crop yield at ambient CO2 concentration. Support pest management Some growers believe that air circulation in greenhouses creates an aerial environment that prevents or delays the incidence of hygrophilous diseases. This effect may be related to the acceleration of evaporation and transpiration in crops. A few reports have struggled to verify the effect of air circulation on the suppression of diseases in high tunnels as shown in Fig. 1. Fig. 1 Schematic diagram of the high tunnels in I) M

Molecular Cloning, Expression and Characterization of a Squalene Synthase Gene from Grain Amaranth (Amaranthus cruentus L.)

Abstract: A gene encoding squalene synthase from grain amaranth was cloned and characterized. The full-length cDNA was 1805-bp long and contained a 1248-bp open reading frame encoding a protein of 416 amino acids with a molecular mass of 47.6 kDa. Southern blot analysis revealed that the A. cruentus genome contained a single copy of the gene. Comparison of the cDNA and genomic sequences indicated that the amaranth SQS gene had 12 introns and 13 exons. All of the exons contributed to the coding sequence. The predicted amino acid sequence of the SQS cDNA shared high homology with those of SQSs from several other plants. It contained conserved six domains that are believed to represent crucial regions of the active site. We conducted qRT-PCR analyses to examine the expression pattern of the SQS gene in seeds at different developmental stages and in several tissues. The amaranth SQS gene was low levels of SQS transcripts at the initial stage of seed development, but the levels increased rapidly at the mid-late developmental stages before declining at the late developmental stage. These findings showed that the amaranth SQS is a late-expressed gene that is rapidly expressed at the mid-late stage of seed development. In addition, we observed that the SQS mRNA levels in stems and roots increased rapidly during the fourto six-leaf stage of development. Therefore, our results showed that the expression levels of SQS in stem and root tissues are significantly higher than those in leaf tissues. In present study provides useful information about the molecular characterization of the SQS clone isolated from grain amaranth. Finally, a basic understanding of these characteristics will contribute to further studies on the amaranth SQS.

Efficacy of Expired Foot-and-mouth Disease O Type Vaccines in Cattle and Buffalo in Lao People’s Democratic Republic

Abstract: Lao People's Democratic Republic (Lao PDR) submitted a request to Japan for 200,000 doses of expired foot-and-mouth disease (FMD) O type vaccines that were in storage for emergency use. Approximately 100,000 animals, consisting of both cattle and Asian water buffalo (Bubalus bubalus bubalis), received the same vaccine twice within one month in Xieng Khouang province in the northeast area of Lao PDR. Concurrently, the efficacy of three-month expired FMD O type vaccine (6PD50 O Manisa) was assessed in serum samples of 90 cattle and 31 buffalo from the field using a Liquid Phase Blocking-ELISA (LPBE) assay. Of these samples, 75 cattle (83.3%) and 24 buffalo (77.4%) were seropositive against the FMD virus (FMDV) O type before vaccination. Testing for non-structural protein (NSP) using the PrioCHECK FMD NS kit showed that many of the animals with high titers in the screening test before vaccination were FMDV-infected animals. Fifteen cattle and seven buffalo with titers 1:32 or under before vaccination exhibited high titers of antibody (1:45-1:1448) one month after the first vaccination and further increased titers (1:362-1:5792) one month after the second vaccination. Nearly all of the cattle (97.6%) had high titers to control FMD 14 months after the second vaccination. To date, no outbreak of FMD has been reported at the study site. Three-month expired FMD O type vaccines induced appropriate immune responses against FMD in both cattle and buffalo.

Involvement of the Rice OsSAUR51 Gene in the Auxin-related Field Resistance Mechanism against Bacterial Blight Disease

Abstract: Pathogenic infection causes auxins to accumulate in plant cells and suppresses plant defense systems. We isolated the OsSAUR51 (Oryza sativa small auxin-up RNA 51) gene as one of the rice field resistance-related genes from a retrotransposon Tos17-tagged ‘Nipponbare’ mutant (XC20) in which field resistance was reduced against several races of bacterial blight pathogens. OsSAUR51 expression was induced by infection of the pathogen and exogenous auxin treatment, whereas the OsSAUR51 gene in the XC20 insertion mutant lost its function due to the Tos17 insertion. We transformed the OsSAUR51 gene with the 1.0 kb OsSAUR51 native promoter into XC20 for complementation analysis and also introduced the OsSAUR51 gene controlled by RexPhi, an enhanced CaMV 35S promoter, into the rice cultivar ‘Dontokoi’ to make transgenic plants with enhanced expression of the OsSAUR51 gene. The OsSAUR51-transformed XC20 recovered its bacterial blight resistance, and the RexPhi::OsSAUR51transformed ‘Dontokoi’ showed enhanced bacterial blight resistance as compared to untransformed ‘Dontokoi’. Auxin accumulation after the bacterial blight inoculation of XC20 was comparatively higher than that of ‘Nipponbare’, but the auxin levels of OsSAUR51-transformed XC20 were lower than those of untransformed XC20. Auxin accumulation after bacterial blight infection in the RexPhi::OsSAUR51-transformed ‘Dontokoi’ plants was repressed as compared to untransformed ‘Dontokoi’. These results suggest that the OsSAUR51 gene induces a field resistance mechanism and represses auxin accumulation after bacterial blight pathogen infection. Discipline: Plant protection Additional key words: mutant, SAUR (small auxin-up RNA), Tos17, Xanthomonas oryzae

Greenhouse Gas Sink-Source Functions of Grassland Ecosystems

Abstract: This review summarizes research on greenhouse gas (GHG) exchange between the atmosphere and grasslands in Japan, identifi es research need, and contributes to advances in the research fi eld of GHG mitigation in grassland ecosystems. Applications of farmyard manure (FYM) and synthetic fertilizers do not reduce the ability of intensively managed grassland soils to oxidize methane (CH4). On the one hand, the use of synthetic fertilizers alone reduces the net ecosystem carbon balance (NECB) of mowed grassland ecosystems. On the other hand, the application of FYM with supplemental synthetic fertilizers at rates determined from the mineralization of FYM increases the NECB at the same yields, due mainly to C brought into the ecosystem as FYM. It also limits further emissions of nitrous oxide (N2O). Precipitation before and after fertilization in the summer months is the key driver of interannual variation in N2O emissions. These fi ndings collectively suggest that the application of FYM with the appropriate reduction in supplemental synthetic fertilizers can maintain soil organic C and maximize the net GHG balance of mowed grassland ecosystems in Japan. Studies on organic matter inputs through root growth and turnover, and models to predict large N2O fl uxes are needed to enhance our understanding of the NECB and net GHG balance of grassland ecosystems. Discipline: Agricultural environment, Grassland Additional key words: carbon balance, farmyard manure, methane, nitrous oxide, soil

The Effects of Day and Night Temperature on the Dry Matter Accumulation of Oriental Hybrid Lily ‘Siberia’ as they Relate to the Photosynthetic and Respiratory Characteristics

Abstract: The net photosynthetic rate on a per-plant basis of the Oriental hybrid lily ‘Siberia’ was low at the leafing stage but increased rapidly at the visible flower bud and flowering stages. The range of 20 to 25°C was the optimum temperature for photosynthesis at the three plant developmental stages under PPFD of 700 to 850 μmol photons m-2 s-1. The respiration rate increased with the increasing temperature quadratically (in aerial plant parts) or exponentially (in underground parts). The ‘Siberia’ plants were grown under three day temperature (DT) conditions of 28°C, 24°C or 20°C, with a night temperature (NT) of 15°C or three NTs of 25°C, 20°C or 15°C, with DT of 25°C in the growth chambers. At the flowering stage, the plants grown under low DT of 20°C had a high dry weight (DW) of the total plant, flowers, bulb, and roots, and a high DW/fresh weight (FW) ratio of the leaves, stem, and bulb. The plants grown under low NT of 15°C had a high DW of the total plant and stem, and a high DW/FW ratio of the leaves and bulb. The plants that were grown under a low NT had a long stem length by the positive DIF effect, which was supported by sufficient dry mater accumulation. The plants grown under low DT of 20°C showed a high relative growth rate (RGR) and net assimilation rate (NAR) from planting to flowering, whereas the NT condition did not affect the RGR or NAR. Discipline: Horticulture Additional key words: cut flower quality, growth analysis, positive DIF effect

Effect of Feeding Milk Replacers on the Tissue Burden of Polychlorinated Dibenzo-para-dioxins, Dibenzofurans, and Dioxin-like Polychlorinated Biphenyls in Suckling Beef Calves

Abstract: To reduce the intake and accumulation of dioxins and dioxin-like compounds in nursing beef calves, the concentrations of seven polychlorinated dibenzo-para-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), and 12 dioxin-like polychlorinated biphenyls (PCBs) were analyzed and compared in the natural milk of grazing beef cows and bovine milk replacers, and in the blood, testis, and adipose tissue of mother-fed and bottle-fed calves at two months of age. The total toxic equivalent quantities (TEQs) of these compounds were approximately tenfold less (P < 0.001) in synthetic milk substitute and starter feed for calves than in natural milk (1.0 and 0.88 vs. 9.28 pg/g-lipid, respectively). The TEQ in the blood of mother-fed calves increased (P < 0.01) two months after birth (1.35 vs. 8.44 pg/g-lipid), whereas no difference in TEQ was found in bottle-fed calves between birth and two months of age (0.94 and 0.93 pg/g-lipid, respectively). Consequently, TEQs in the blood, testis, and adipose tissue were less (P < 0.05) in bottle-fed calves as compared with mother-fed calves at two months of age (0.93 vs. 8.44, 4.97 vs. 21.7, and 5.17 vs. 18.1 pg/g-lipid, respectively). Regarding individual congeners, the concentrations of dioxins with four or five chlorine substitutions were lower (P < 0.05) in synthetic milk substitute and starter feed than in natural milk, whereas the concentrations of hepta- and octa- chlorinated congeners were conversely higher in synthetic milk substitute and starter feed. Similarly, the accumulation of tetra- and penta- chlorinated congeners in adipose tissue of bottle-fed calves was lower (P < 0.01) than that in mother-fed calves. In contrast, congener specific accumulation characteristics like PCDDs were not observed in PCDFs and dioxin-like PCBs, and none of these congeners detected in bottle-fed calves were greater than that found in mother-fed calves. These results suggest that the feeding of milk replacers can markedly reduce the intake and accumulation of dioxins and dioxin-like compounds in nursing beef calves as compared with natural feeding, because the milk replacers contain preferably lower concentrations of these compounds than in natural milk.

Effect of the Interaction Between Monsoon Currents and Waves on the Morphological Processes along the Mekong River Delta Coast

Abstract: One of the longest rivers in the world, the Mekong River flows through eight estuaries into the East Sea off Vietnam. In recent decades, the complex morphological evolution of the Mekong River Delta coast has affected the livelihoods of local people and the development of Vietnam’s major economic area in the south. In this study, large-scale numerical models were created to simulate the long-term morphological processes along the Mekong River Delta coast. By using these models, key factors such as river currents, tides, sediment discharge, monsoon currents, waves, and salinity were calculated under various conditions, including seasonal variations of river flow, monsoon surface sea currents, and waves. The results show that the river flow rate determines erosion and deposition in the river. Furthermore, the river current combined with tidal current governs the development of narrow passages and islets. The effect of the interaction between the monsoon current and waves on the morphological processes of the coastline is significant. The monsoon current plays a major role in changing the shoreline, whereas wave action is a secondary factor that intensifies shoreline erosion, which is primarily influenced by sea current.

Allometric Equations for Tropical Seasonal Deciduous Forests in Cambodia: A Method of Estimating Belowground Tree Biomass with Reduced Sampling Loss of Roots

Abstract: There is an urgent need to estimate the biomass of tropical seasonal forests in central Indochina, which have suffered from deforestation and degradation. However, allometric equations specific to such forests are limited. In this study, we destructively sampled 28 trees in a deciduous forest in Kratie Province, Cambodia, and developed new allometric equations for estimating the tree-level biomass of aboveground woody parts (trunk + branches), leaves, total aboveground parts (trunk + branches + leaves), and that of belowground parts (BGB). The sampling of belowground parts is usually very laborious and time-consuming, and entails inevitable root loss during excavation. Thus, it is difficult to accurately quantify tree-level BGB, especially for large trees. We used a new sampling method (called the mound method) to reduce the sampling loss of BGB. The percentage of BGB sampling loss (ratio of sampling loss estimated by the mound method to total BGB) averaged 28.9%. Our models estimated the stand-level biomass of a deciduous dipterocarp forest in Kratie to be 81.9 ± 45.1 Mg ha1. The allometric equations and tree-level biomass data presented here will support activities related to REDD+. Discipline: Forestry and forest products Additional key words: deciduous dipterocarp forest, destructive sampling, forest biomass estimation, REDD+, root system This study was conducted as part of a research program (Global Environment Research Fund A-0802, “Development of the Forest Degradation Index and the Carbon Emission Estimation Method using PALSAR data”) supported by Japan’s Ministry of the Environment, and partly supported by a research project (“Emergency Project to Develop the Structure of Promoting REDD Action”) funded by the Forestry Agency of Japan. Present address: 7 Graduate School of Agriculture, Kyoto University (Kyoto, Kyoto 606-8502, Japan) *Corresponding author: e-mail monda.yukako.2m@kyoto-u.ac.jp Received 13 April 2015; accepted 22 February 2016. Introduction The tropical seasonal forest is a major type of vegetation in Cambodia, Laos, and Myanmar, where serious deforestation has occurred (FAO 2010). Appropriate and simple methods of estimating forest biomass, such as allometric equations, are urgently needed for accurate estimates to support initiatives such as REDD+ (“Reducing Emissions from Deforestation and forest Degradation and the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries”: https://unfccc.int/methods/redd/methodological_guidance/items/4123.php). There are two main types of tropical seasonal forest: evergreen and deciduous. In

Occurrence of Delayed Leaf Senescence of Soybean Caused by Rhizoctonia Aerial Blight in Japan

Abstract: In 2004, an outbreak of Rhizoctonia aerial blight on soybeans planted after rice in paddy fields in Hiroshima Prefecture, Japan was also associated with delayed leaf senescence (DLS, or green stem/ bean syndrome). The isolated Rhizoctonia solani was characterized as anastomosis group AG-1 IA, identical to that of the R. solani causing rice sheath blight. The relationship between aerial blight and soybean DLS, which are also problems in Japan, was examined through field inoculation testing of the rice sheath blight pathogen on soybean plants. In some plots, fungicides (azoxystrobin, flutolanil or validamycin A) were sprayed on the soybean foliage after inoculation, and some plots received frequent overhead irrigation to promote disease. There was a high incidence of the disease and DLS in the inoculated and frequently irrigated plots without the application of fungicide. Without fungicides, the yield from diseased soybeans was 12-35% lower than that in noninoculated control plots. The fungicide sprays described above were effective in controlling DLS and yield loss from the disease. We thus clearly showed that Rhizoctonia aerial blight of soybean caused by the rice sheath blight pathogen is at least one of the causes of soybean DLS. Frequent rainfall is likely to promote the disease and resulting DLS. Discipline: Plant disease Additional key words: fungicide, green bean/stem syndrome, ISSR-PCR, Rhizoctonia solani AG-1 IA, rice sheath blight

Serovar and Antimicrobial Resistance Profiles of Actinobacillus pleuropneumoniae Isolated in Japan from 2006 to 2011

Abstract: 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. Discipline: Animal health Additional key words: swine, pleuropneumonia Present address: 2 Kagoshima Chuo Livestock Hygiene Service Center (Higashi-Ichiki, Kagoshima 899-2201, Japan) 3 Kyushu Research Station, National Institute of Animal Health, National Agriculture and Food Research Organization (Kagoshima, Kagoshima 891-0105, Japan) *Corresponding author: e-mail itohiroy@affrc.go.jp Recieved 27 November 2014; accepted 7 May 2015. 11_Kamimura_p073-077.indd 73 2015/11/26 21:15:56 74 JARQ 50 (1) 2016 S. Kamimura et al. Materials and methods Forty-eight strains of A. pleuropneumoniae (isolated from 2006 to 2011 from 47 farms in 11 prefectures in Japan) were sent to our diagnostic laboratory at the National Institute of Animal Health for serotyping. Of the 48 strains, 46 were isolated from different farms. The other two strains of serovar 1 (isolated in 2006 and 2008 at farm A) were subjected to antimicrobial resistance tests to examine ARP changes. A. pleuropneumoniae strain S1421 (= strain ATCC27090) was used as a quality control in each test. A. pleuropneumoniae was grown on tryptic soy agar (Difco, Sparks, MD) supplemented with 5% horse blood and 100 μg/mL β-nicotinamide dinucleotide at 37°C with 5% CO2, and after being suspended in phosphatebuffered saline containing 20% glycerol, it was stored at -80°C until use. Serotyping was carried out with rabbit antisera prepared against serovar reference strains by conducting slide agglutination tests, and when necessary, by immunodiffusion tests (Mittal et al. 1992), along with polymerase chain reaction for genes involved in capsular polysaccharide biosynthesis (Angen et al. 2008, Ito 2010, Zhou et al. 2008). For the antimicrobial resistance tests, we cultured bacterial strains on chocolate agar at 37°C with 5% CO2 as per the Clinical and Laboratory Standards Institute (CLSI) standards and recommendations (CLSI 2013). The resistance of these strains to the following six antimicrobial agents was tested by using the disc diffusion method (Sensi-Disc, Japan Becton Dickinson, Tokyo), as per the CLSI (2013) standards and recommendations: penicillin G (PCG) 10IU, ampicillin (ABPC) 10 μg, oxytetracycline (OTC) 30IU, sulfonamide (sulfisoxazole (SIX)) 250 μg, chloramphenicol (CP) 30 μg, and norfloxacin (NFLX) 10 μg. Each strain was classified as being resistant, susceptible, or intermediate to the antimicrobial agents tested, in accordance with breakpoints proposed by the Comite de l’Antibiogramme de la Societe Francaise Microbiologie (CASFM 2010) as previously described (Vanni et al. 2012), except for SIX and NFLX, for which the criteria of the National Committee for Clinical Laboratory Standards (NCCLS; later renamed CLSI) were applied (NCCLS 2002). Results and discussion Of the 48 strains, 5 (10.4%) were serovar 1, 29 (60.4%) were serovar 2, 7 (14.6%) were serovar 5, 1 (2.1%) was serovar 6, 1 (2.1%) was serovar 7, 1 (2.1%) was serovar 12, and 4 (8.3%) were serovar 15, showing that the most prevalent serovars were 2, 1 and 5, as found in several previous reports (Asawa et al. 1995, Fukuyasu et al. 1996, Morioka et al. 2006, 2008, Yoshimura et al. 2002). Despite the low number of serovar 15 strains isolated in the present study (n=4), serovar 15 has been the fourth most prevalent serovar of strains sent to our diagnostic laboratory for serotyping (Table 1). This prevalence is particularly noteworthy because serovar 15 was not isolated prior to 2008. The rapid rise in the reported cases of serovar 15 strains suggests that this serovar may Table 1. Distribution of antimicrobial resistant strains of Actinobacillus pleuropneumoniae isolated in Japan from 2006 to 2011 Serovar No. of strains (%) PCG ABPC OTC SIX CP NFLX 1 5 (10.4) 3 (60) 3 (60) 5 (100) 4 (80) 4 (80) 0 (0) 2 29 (60.4) 4 (13.8) 1 (3.4) 2 (6.9) 11 (37.9) 5 (17.2) 0 (0) 5 7 (14.6) 3 (42.9) 0 (0) 7 (100) 1 (14.3) 0 (0) 0 (0) 6 1 (2.1) 0 (0) 0 (0) 1 (100) 0 (0) 0 (0) 0 (0) 7 1 (2.1) 0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 12 1 (2.1) 0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 15 4 (8.3) 2 (50) 2 (50) 4 (100) 2 (50) 0 (0) 0 (0) Total 48 (100) 12 (25) 6 (12.5) 19 (39.6) 18 (37.5) 9 (18.8) 0 (0) 11_Kamimura_p073-077.indd 74 2015/11/26 21:15:56 75 Serovar and Antimicrobial Resistance of A. pleuropneumoniae have become important relatively recently in Japan, as it has in Australia (Blackall et al. 2002). Table 1 lists the prevalence of resistant strains of the 48 A. pleuropneumoniae strains tested; Table 2 lists the ARPs of the strains where 31.3% (n=15) showed no resistance to any of the six antimicrobials used, and 33.3% (n=16) were resistant to only one antimicrobial, indicating that almost all of the antimicrobials used are effective for swine pleuropneumonia treatment. All of the tested strains were susceptible to NFLX, one of the fluoroquinolones recommended for use as a last-resort antimicrobial (Burch 2008). The strains tested in the present study (Table 1) showed a low prevalence of strains resistant to ABPC (12.5%), which is recommended as the first-choice antimicrobial for swine pleuropneumonia treatment (Burch 2008). A similar low prevalence of ABPC-resistant strains (2.0%-12.4%) in A. pleuropneumoniae was also observed from 1989 to 2005 (Asawa et al. 1995, Fukuyasu et al. 1996, Morioka et al. 2008). Of the 48 strains tested, 12 PCG-resistant strains were identified, half of which were ABPC-resistant and the remaining six were ABPC-susceptible. The underlying reason for the difference in resistance to the two β-lactams (PCG and ABPC) remains to be elucidated. A low prevalence of PCG-resistant strains (4.4%-13.6%) in A. pleuropneumoniae was observed from 1989 to 2000 (Asawa et al. 1995, Fukuyasu et al. 1996, Morioka et al. 2006, Yoshimura et al. 2002). However, the present study showed a slightly increased prevalence of PCG resistance (25.0%) in strains isolated from 2006 to 2011. The two A. pleuropneumoniae serovar 1 strains isolated in 2006 and 2008 at farm A exhibited different ARPs. Specifically, the strain isolated in 2006 was resistant to OTC-SIX-CP, but the 2008 strain was resistant to PCG-ABPC, as well as to OTC-SIX-CP. The ARPs of three other strains isolated from different pigs at farm A in 2006 were further examined in addition to the 48 strains listed in Tables 1 and 2, in order to rule out the possibility that PCG-ABPC-resistant strains may have been already present at farm A in 2006. Consequently, all three strains were found to be resistant to OTC-SIX-CP, but sensitive to PCG-ABPC (data not included in Tables 1 and 2). These results indicate that PCG-ABPC-susceptible clones may have acquired PCG-ABPC resistance or may have been replaced by PCG-ABPC-resistant clones at farm A, resulting in the ineffectiveness of PCG-ABPC for treatment. This observation demonstrates the chronological Table 2. Antimicrobial resistance profiles (ARPs) of 48 Actinobacillus pleuropneumoniae strains tested No. of antimicrobials to which the strains showed resistance ARPs No. of strains (%) Serovar Year isolated 2006 2007 2008 2009 201

Development and Adaptability of a Topsoil Removal Machine for Decontaminating Peripheral Areas of Agricultural Land

Abstract: 5 YANMAR Co., Ltd. (Osaka, Osaka 530-8311, Japan) Abstractand 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 embank- ments 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.