We adopted ‘inter-row strip tillage’ (IST), which involves conducting tillage between rows and sowing on no-tillage soil, to cultivate soybeans in upland fields converted from paddy fields (UFCP) and examined the effect on soil water content, growth and soybean yield. The three phase of no-tillage soil in IST differs from soil harrowed via conventional tillage, which shows lower solid and liquid phases. No-tillage soil in IST showed a larger water content under drought conditions and less fluctuation of the liquid phase between conditions of drought and excess moisture compared to those of harrowing soil in conventional tillage. The plants in IST had more root nodules and showed higher SPAD values. They were also longer, with more nodes on the main stem, and a larger dry weight at the flowering stage. The IST yield exceeded that in conventional tillage, due to the higher number of pods and 100-kernel-weight. The factors of superior growth and higher IST yield were attributed to the property of the no-tillage soil in IST, which alleviates the fluctuation of the soil water content in UFCP. The relationships between soil permeability and property remain to be evaluated, while there is also a need to improve the IST operational efficiency.

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Next-generation sequencers have accelerated the advancement of virus hunting or virus detection by metagenomic analysis. Conversely, earlier works enabled virus detection with classic Sanger sequencing by elaborating sample preparation/processing techniques. In this review, we introduce virus hunting technologies both with and without cutting-edge sequencing technology and subsequently discuss the possibility that combining these technologies may extend the application of sequencing-based virus detection from scientific research to everyday diagnostics. Finally, we offer an outlook for another type of technology that leads to pathogen identification using the sequence data obtained in sequencing-based virus hunting.

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The use of natural enemies instead of chemical pesticides has been increasing worldwide. Although non-native natural enemies are beneficial and commonly used as biological control agents, the risks of non-target effects caused by their release are of growing concern. Phytoseiid mites are a very common choice as introduced biological control agents. In Japan, 8 species of non-native phytoseiid mites, one of which is the same as the native type but originates from a non-native population, have been introduced for crop pest control. There is concern about the influence of the introduced phytoseiid mites on native phytoseiid mites that occupy a similar habitat, but very few risk assessments of these phytoseiid mites have been carried out in Japan. In this paper, we estimate the risks of the non-target effect caused by the release of these introduced non-native phytoseiid mites by using the risk indexes proposed by Mochizuki (2010), and briefly present the results of monitoring the species considered at risk from the release of non-natives.

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Mesh data of air temperature in a geographical information system are useful for the precise management of farmland with unique meteorology, especially in hilly and mountainous areas. However, there have been few cases in which the application of mesh data has increased agricultural productivity because the mesh data have been too incomplete to be handled as practical data for agriculture. Thus, a practical method of developing mesh data of air temperature is reviewed; this paper is a review of author studies. Air temperature data are estimated from the variation in air temperature between an estimation site and an existing observation site. There are two factors behind the differences in air temperature: the radiative cooling intensity at the estimation site and the radiative cooling intensity at the existing observation site. Furthermore, a method of compiling high-resolution mesh data from coupled general circulation model data to make quantitative assessments of the effects of climate change is presented. A correction model of downscaling data employing a regional climate model was developed through stepwise multiple regression analysis using the variation in monthly mean air temperatures between the observation and regional climate model output as a dependent variable and geographical factors as independent variables.

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Cost recovery and irrigation management transfer (IMT) for irrigation/drainage infrastructure is crucial for appropriate construction/reconstruction and operation and maintenance (O&M) of infrastructure under limited governmental funding. The concept of cost recovery and IMT remains a new one in Egypt and there are several issues to be resolved. The current status and issues of cost recovery and IMT, especially O&M cost, in Egypt are reviewed and analyzed based on World Bank′s projects and JICA′s experience. Firstly, the current transitional status was identified based on World Bank′s projects, followed by identification of the remaining issues based on JICA′s experiences and finally future directions to achieve cost recovery and IMT. Providing the required training to Government staff, staff of water users′ associations (WUAs), and farmers is key to ensure they fully understand the concept and achieve the cost recovery and IMT.

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The cultivation variations and interrelations among quality characteristics in two-rowed, hull-less pearling barley were studied to obtain basal information for high quality production of this new class of barley in Japan. Samples of the two-rowed, hull-less cultivar “Yumesakiboshi” grown under various cultivation conditions were pearled and analyzed for the relationships between different quality characteristics. The key quality problem for two-rowed hull-less barley appeared to be the high rate of grain breakage by pearling, the rate of which positively correlated with the thousand-grain weight and negatively correlated with grain hardness. Samples with a thousand-grain weight of >40 g showed an extremely high broken-grain rate. The pearl whiteness had a negative correlation with the steely grain rate. Both the steely grain rate and the pearl whiteness showed significant correlations with grain hardness. However, the effect of grain protein content on the steely grain rate showed yearly fluctuation. The hard grain characteristics reduced the broken-grain rate, but adversely affected the steely grain rate and the pearl whiteness. The results of this study indicate that for the high quality production of two-rowed, hull-less barley, the cultivation techniques of limiting the thousand-grain weight to less than 40 g and reducing the steely grain rate are the most promising approaches.

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An effective means of supplying food to Cotesia vestalis, the larval endoparasitoid of the diamondback moth, Plutella xylostella, was examined in a laboratory and an experimental small greenhouse. Compared to the red and blue boards, yellow boards significantly attracted parasitoids in the laboratory and in the small greenhouse, the yellow feeding site was more effectively utilized by parasitoids than the white one. The parasitoid tended to utilize a feeding site hung 50 cm above ground more than one hung 200 cm above ground, hence we concluded that color and height were important factors for the recognition of the feeding sites by C. vestalis.

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In this study, we demonstrate changes in leaf morphological and physiological traits with tree height from dark understory to bright canopy conditions in various tree species in the Cambodian tropical dry evergreen forest. The vegetation mainly consisted of Dipterocarpaceae and Myristicaceae and the canopy trees usually reached 30-40 m in height. We investigated 25 individuals of 18 tree species ranging from 0.8 to 33 m in height. We measured the leaf photosynthetic rate, stomatal conductance and respiration rate for 3 to 5 leaves per sampling position in the early dry season. All leaves were then divided into two parts: one for measuring dry weight, nitrogen content and δ¹³C; the other for observation of leaf morphology. The leaf morphological traits, such as leaf mass per area (LMA), cuticle thickness, palisade layer thickness, leaf hardness and stomatal density increased linearly with tree height. The leaf nitrogen content per unit leaf area (N_area) peaked at 10 m from the ground, though the nitrogen content per unit dry leaf mass (N_mass) decreased linearly with tree height. Higher LMA, cuticle thickness and hard leaves in canopy condition may contribute to high drought tolerance and physical strength. The leaf-area-based photosynthetic rate (A_max-area) peaked at an intermediate tree height of approximately 10 m, and then decreased toward the upper canopy. In contrast, the leaf-mass-based photosynthetic rate (A_max-mass) decreased linearly with tree height. Reduction of leaf nitrogen content and stomatal conductance mainly limit photosynthetic capacities with tree height. Overall, many leaf morphological traits could be summarized in a simple and significant relation with tree height, though increasing tree height, which is related to the micro-climatic gradient, leads to both nitrogen and stomatal constraints of leaf photosynthetic capacities, even when considering many different tree species.

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The antifungal constituents from the heartwood of Calophyllum symingtonianum (bintangor bukit; Clusiaceae) were investigated. Methanol extracts, n-hexane-solubles, ethyl acetate-solubles and ethyl acetate-insolubles obtained from the heartwood of C. symingtonianum were subjected to antifungal assay against the brown-rot fungus, Gloeophyllum trabeum, and the white-rot fungus, Pycnoporus sanguineus. n-Hexane-solubles and methanol extracts showed the highest activity against G. trabeum, followed by ethyl acetate-solubles. n-Hexane-solubles showed the highest activity against P. sanguineus, followed by methanol extracts and ethyl acetate-solubles. Two major xanthones, 1,3,5-trihydroxy-2-(3-methylbut-2-enyl)xanthone (1) and 6-desoxyjacareubin (2) were isolated from ethyl acetate-solubles and n-hexane-solubles, respectively, and the structures of these compounds were determined. They were isolated for the first time from C. symingtonianum. Xanthones 1 and 2 were active against the both fungi and showed significantly high activity against G. trabeum and P. sanguineus, respectively. The activities of these antifungal xanthones were comparable to or higher than those of the positive control, glycyrrhizic acid dipotassium salt. The results suggested the significant potential of the heartwood of C. symingtonianum as a source of fungistats.

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As a feasibility study for applying a simplified method to estimate CO₂ emissions from deforestation and forest degradation in tropical forests, we estimated the nationwide forest tree biomass carbon stock using data from 100 permanent sampling plots (PSPs) set by the Forestry Administration, Cambodia in seasonal forests in Cambodia. Averaged tree carbon stocks and SE-Standard error were at 158.8 ± 7.3 Mg C ha^-1 for evergreen and semi-evergreen forests and 55.2 ± 6.9 Mg C ha^-1 for deciduous forests in 1998 (the first census) and for the second census in 2000-2001, 163.8 ± 7.8 Mg C ha^-1 and 56.2 ± 6.7 Mg C ha^-1, respectively. The averaged tree biomass carbon stock differed significantly between the two forest types. Using the forest cover for 2006 and the averaged carbon stock for 2000-2001, the national-level forest tree carbon stock in the early to mid-2000s was estimated at 824.2 ± 39.2 Tg C for evergreen forests and 263.9 ± 31.3 Tg C for deciduous forests, and 1,088.1 ± 50.2 Tg C in total. By repeating this calculation for all forest areas by remote sensing and averaged tree carbon stock via ground-based measurement with PSPs, we could monitor the total tree carbon stock in nationwide forests in Cambodia. We also presented the possible reasons for uncertainty related to the present tree biomass carbon stock of forests and recommendations in order to improve the accuracy of the carbon stock using PSP systems in Cambodia.

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A database of plant diseases reported in Japan and a Web-based data-retrieval system to search for information stored in the database have been developed. The retrieval system is linked with the database on microorganism genetic resources registered in the Genebank Project of the National Institute of Agrobiological Sciences (the NIAS Genebank), which provides access to detailed genetic information on strains of these microorganisms. The NIAS Genebank manages the registration of so-called “passport” data for these genetic resources and controls their storage to make samples available to researchers worldwide. Data management software has been developed to register the receipt, storage, testing, and multiplication of these genetic resources. Search software has also been developed to seek suitable genetic resources based on several search criteria to facilitate their distribution from the stocks stored in the NIAS Genebank. DNA sequence data for the D1/D2, 18S, and internally transcribed spacer ITS (ITS1-5.8S-ITS2) regions of rDNA and for the coding region of the β-tubulin gene for many of the conserved microorganisms can be accessed from the NIAS Genebank Web site. The database on Japanese plant diseases and the NIAS Genebank search system are expected to become increasingly useful tools for research and education related to microorganisms and their genetic data, as well as for improving plant protection and food security.

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