This paper reviewed the contributions of Japan to rice research through its partnership with the International Rice Research Institute (IRRI), which started in 1960. Japanese scientists were seconded to work at the IRRI headquarters or hired as full-time staff to conduct rice research in the fields of breeding, pathology, physiology, agronomy, and social sciences. Among them is Dr. Akira Tanaka who played a key role in the development of IR8, a rice variety credited for paving the way for the first Green Revolution. To disseminate research outputs from agronomic research on rainfed rice in Asia to farmers, IRRI developed an ICT-based decision support systems (i.e. weather-rice-nutrient integrated decision support system or WeRise) which are ideal platform to enable farmers to access database from various fields of rice research. These web-based technologies are also accessible through mobile devices. Web-based technologies can help accumulate big data that can be used to promote data-driven solutions and enable informed decision-making to help rice farmers adapt to current and future climate. Analysis of big data from various web-based technologies is still a researchable area where IRRI and Japan can work together to exploit valuable information from past researches and further contribute to sustainable development through rice research.

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The BADH1 was characterized by investigating its association to aroma, drought and salinity stress through sequence and gene expression analysis using the selected aromatic rice accessions from Central Luzon State University, Philippines. Polymorphisms including SNPs, were observed in genomic analysis between the resistant check and the susceptible varieties during saline condition. On the other hand, BADH1 transcript level in tolerant varieties revealed that during salt treatment, the salt tolerant check Pokkali and moderately salt tolerant accession Leyte Special have increased transcript level compared to non-treated saline condition relative to actin. The downstream investigation of the BADH1 using genomic and transcriptomic approach is important information to elucidate the molecular mechanism of fragrance development among aromatic rice in CLSU and its response to abiotic stresses.

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Early recognition of the importance of roots for drought resistance, and the diversity in rice root architecture, provided a strong foundation for drought research at the International Rice Research Institute (IRRI). IRRI was founded in 1960, and large efforts for research on root growth in response to drought were ongoing by the mid-1970s, with an emphasis on deep root growth, formation of coarse nodal roots, and the root pulling force method. In the 1980s, aeroponic studies on root morphology and anatomy and line-source sprinkler field studies were commonly conducted. The use of crosses to better understand the genetics of root traits started in the 1980s. Further characterization of the genetics behind root traits was conducted in the 1990s, specifically the use of molecular markers to select for root trait QTLs. A shift toward rainfed lowland experiments in addition to upland conditions began in the 1990s, with increased recognition of the different types of drought stress environments and characterization of root water uptake. In the 2000s, drought breeding efforts moved from selection of root traits to direct selection for yield under drought. Today (the 2010s), we have identified two major drought-yield QTLs to be related to root traits, and phenotyping for association mapping of genes related to root traits and functions is underway. After direct selection for yield during the past decade that is now approaching impact at the farm level, we are seeing that root traits are indeed involved in improved yield under drought.

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Farms in Southeast Sulawesi Province, Indonesia, historically grow upland rice crops that utilize the slash-and-burn farming system. However, little is known about grain quality and the differences between upland rice varieties in this region. In the present study, growth and grain yield were measured to elucidate the characteristics of traditional upland rice varieties grown by local farmers. Additionally, amylose and protein content were measured to understand their characteristics. In this region, farmers predominantly grew traditional rice varieties, which were deemed as tropical japonica based on the measured agronomic traits. These traditional varieties were highly varied in terms of grain appearance and yield-related factors. Grain yield in the traditional varieties (3.0 t ha-1 on average) was inferior to that of Lampung (4.0 t ha-1 on average), an improved variety newly introduced from outside the region. In particular, Lampung tended to have a higher spikelet number per m2 than that of the traditional varieties. The protein and amylose content varied depending on the different varieties. Amylose content of eleven upland rice varieties was determined, with eight varieties characterized as sticky rice, two as non-glutinous varieties, and one as an extremely low amylose variety. These results indicate that this region contains valuable upland rice varieties, and this information is useful for future genetic resource studies.

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This article outlines a notion of postcolonial Philippine science. First, it touches on the links between science, medicine, the Cold War, and nation building. Second, it examines the niche occupied by applied sciences, particularly nutrition, agriculture, and medicine, in nation building. Between 1946 and 1965, Philippine presidents understood science functionally, in terms of harnessing the country’s natural resources for economic development; and strategically, in terms of the Philippines being a regional leader of the free world in Southeast Asia. To realize the Philippines’ Cold War aspirations, they mobilized technical assistance from the US. The Bataan Rice Enrichment Project (1946–49) and the establishment of the International Rice Research Institute (1962) indicated a shift in the emphasis of US assistance from economic aid to technical cooperation in the field of nutrition and agriculture.

Through a close study of the Philippine Medical Association, this article examines inner tensions between physicians who advocated an individualized treatment of disease and those who advocated mass campaigns. Between 1946 and 1965, a mobilization mentality suffused the practice of science in the Philippines such that the pursuit of knowledge would lead to unanswered Cold War questions—particularly socialized medicine—expanding healthcare access to rural areas.

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(±)-γ-Irones (1/9 mixture of cis-and trans-isomers and pure trans-γ-irono) were synthesized via the intramolecular Diels-Alder reaction starting from 2, 4-hexadienyl aniline derivative and β, β-dimethylacryloyl chloride.

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This study aimed to investigate the adoption of Highland Terrace Paddy Cultivation Technology (HTPCT) in Northern Thailand. HTPCT was promoted by the Rice Department in 2003 in four provinces of Northern Thailand under the Royal Development Project. Previous studies showed increased yields using HTPCT while cost of converting sloping lands into terrace paddy can be recouped in a few years. However, despite the promotion of the technology, adoption had not been widespread. To understand the limitations in the adoption process, quantitative and qualitative research was conducted in 5 villages of Chiang Mai and Mae Hong Son provinces located in Doi Ompai Mountain. Results show that overall the respondents had high level of adoption but for two practices, namely, soil fertilizer management and sequential cropping system and livestock production, the respondents had moderate level of adoption. Further, the two production practices were only partially practiced by the farmers. This means that even if the adopters converted their upland rice areas to terrace paddy, they still used some traditional technologies and did not follow all recommended HTPCT practices. The common problems mentioned by the respondents in practicing HTPCT were water and labor shortage, difficulty of land preparation, lack of bio-pesticides and green manure seeds, familiarity with traditional cultivation and their superstition which worked against widespread adoption. Thus, a model in promoting HTPCT in Northern Thailand is proposed. The model takes into consideration the necessary policies, roles of various stakeholders and joint learning among farmers, extension workers and researchers in each step of HTPCT promotion.

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Since the establishment of the International Rice Research Institute (IRRI) in 1960, breeding effort in varietal improvement for irrigated lowland has passed four decades. Breeding of semi-dwarf rice varieties such as IR8 at IRRI during first decade from 1960 to 1969 resulted in quantum leaps in yield potential, which marked the green revolution in Asia. During the second decade from 1970 to 1979, the primary emphasis of rice improvement has been directed towards incorporation of multiple disease and insect resistance and shortening of growth duration. Grain quality was the main target of crop improvement at IRRI during the third decade from 1980 to 1989. The fourth decade from 1990 to 1999 and beyond was focused again on the improvement of yield potential by developing hybrid rice and new plant type. Up to 1999, 46 indica inbred varieties and 2 indica/indica hybrid rice varieties were developed by IRRI and released in the Philippines for the irrigated lowland rice systems. Large-scale adoption of these improved varieties under modern crop management practices has resulted in a dramatic increase in rice production in major rice-growing countries. The hybrid varieties between indicas increased yield potential by 9% under the tropical conditions. New plant type (NPT) breeding has not yet resulted in an increase in yield potential. The second generation NPT developed by crossing tropical japonica with indica has demonstrated some promising results in terms of improvements in yield potential, disease and insect resistance, and grain quality.

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Worldwide increasing water demands have made alternate wetting and drying (AWD) irrigation an attractive water-saving technology for paddy rice farming. With AWD, rice paddies are intermittently irrigated, except during the rooting and flowering stages, reducing water use by 15%-40%. We assessed AWD uptake by comparing the standardized AWD used by official institutions and the practiced AWD used by farmers in An Giang Province, Mekong Delta, Vietnam. We observed that 1) farmers did not use plastic pipes to measure the water level, although these allow assessment of the correct timing for watering and 2) farmers also practiced AWD during the rainy season, despite it originally being developed as a water-saving technology. These modifications indicate that farmers have adapted AWD for use in their local farming conditions. Agrarian certification systems should be used to increase AWD uptake; however, these require standardized procedures. Therefore, this disparity between the standardized and practiced technology should be addressed to improve AWD uptake.

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半島マレーシアの水田では, 1980年代以降の急速な水稲直播栽培の普及に伴って雑草問題が深刻化している。特にノビエ, アゼガヤ等の一年生イネ科雑草の多発が問題となっている。そこで, 直播水田におけるアゼガヤ (Leptochloa chinensis (L.) Nees) の生育と雑草害の程度を検討するために, 半島マレーシア北西部に位置するムダ灌漑地区で圃場試験を実施して, アゼガヤの発生密度が直播水稲の収量と収量構成要素に及ぼす影響を解析し, 以下の結果を得た。
アゼガヤの初期生育が水稲播種後の激しい降雨によって一時抑制されたため, 播種後45日目における水稲の草丈と茎数に及ぼすアゼガヤの発生密度の影響は認められなかった (Table 1)。しかし, 収量構成要素の中では千粒重がアゼガヤの発生密度の影響を受けて有意に減少し (Table 2), m²当たりの穂数もアゼガヤの発生密度が高まるにつれて大きく減少した (Fig. 5)。直播水稲の穀実収量は, アゼガヤの密度の増加に伴いm²当たりの穂数および粒数に同調して減収した (Fig. 2, Fig. 3, Fig. 4)。アゼガヤの密度が16個体/m²以上になると水稲収量は有意に減収し, 40個体/m²では無発生区の収量 (4.44t/ha) に対して35%の減収を記録した (Table 2)。
以上の結果から, 直播水田におけるアゼガヤの生育は, 初期は緩慢であるが発生後1ヶ月を経過するとその生育は旺盛になること, アゼガヤが多発した場合には, 生育中期以降の穂数決定時期から登熟期間にかけてアゼガヤと水稲の間に強い競合が起こり, 水稲の減収を招くことが明らかになった。

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From the point of view concerning the equilibrium between molten iron and slag deposited with electrode, we studied the influence of TiO₂ or ilumenite, in the FeO-MnO-SiO₂ coating saturated with SiO₂, on weld metal obtained. Especially, effects on its total silicon content, manganese content and quantity of inclusions were researched. The total silicon content of weld metal increases and the total manganese content decreases with the increase of TiO₂ or ilumente content of coating.
The increase of silicon content results the decrease of oxygen content and total quantity of inclusions of weld metal. Accordingly, it was observed by a microscope with 400 magnification that the quantity of inclusions decreases with the increase of TiO₂ or ilmenite content. But on the case of microscopic examination with 1200 magnification the reverse tendency was observed. That is, the higher dispersion of fine glassy inclusions was recognized on the matrix of weld metal with the increase of TiO₂ or ilumenite content of coating.

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Data from breeding, including phenotypic information, may improve the efficiency of breeding. Historical data from breeding trials accumulated over a long time are also useful. Here, by organizing data accumulated in the National Agriculture and Food Research Organization (NARO) rice breeding program, we developed a historical phenotype dataset, which includes 6052 records obtained for 667 varieties in yield trials in 1991–2018 at six NARO research stations. The best linear unbiased predictions (BLUPs) and principal component analysis (PCA) were used to determine the relationships with various factors, including the year of cultivar release, for 15 traits, including yield. Yield-related traits such as the number of grains per panicle, plant weight, grain yield, and thousand-grain weight increased significantly with time, whereas the number of panicles decreased significantly. Ripening time significantly increased, whereas the lodging degree and protein content of brown rice significantly decreased. These results suggest that panicle-weight-type high-yielding varieties with excellent lodging resistance have been selected. These trends differed slightly among breeding locations, indicating that the main breeding objectives may differ among them. PCA revealed a higher diversity of traits in newer varieties.

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Previously, we showed that upland rice (Oryza sativa L.) had a higher response to organic nitrotgen applied as rice bran than maize (Zea mays L.). We proposed three hypotheses for the results. Firstly, rice has a greater ability to compete with microorganisms for inorganic nitrogen. Secondly, rice is superior in the uptake of ammonium, amino acids and peptides. Thirdly, the mineralization in rice root zone occurs more actively as compared to other crops. We investigated the protease activity in the soil to clarify how much the third hypothesis contributed to the nitrogen uptake of rice, We cultivated rice, maize and soybean (Glycine max Merr.) in small pots (5 × 5 × 5 cm) with Andosol in a glasshouse at the National Institute of Agro-Environment Sciences, Tsukuba, Japan, in 1995. We took the soils in rhizosphere and non-rhizosphere separately 26 and 34 d after sowing, and then measured the protease activity of these soils using casein and Z-phe-leu as the substrates. The soil protease activity of maize was higher than that of rice, and soybean was found to be the medium of these crops. These results show that the rhizosphere effect related to nitrogen mineralization such as protease activity does not specifically occur in rice cultivation soil. The other hypotheses are to be investigated to enable comprehension of the strong ability of nitrogen uptake by rice.

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In the subjects of Down's syndromes from 3 to 22 years of age (48 males, 26 females), we examined the appearance rate of morphological abnormalities about the giant teeth, microdont and peg-shaped teeth. 1. The appearance rate of morphological abnomalities of the permanent teeth crown for the male was 57.8% (26/45), for the female 52.2% (12/23), very high frequency. The sexual difference was not almost acknowledged. 2. It was showed that the frequency of morphological abnormalities about the present permanent teeth for the male was 17.4% (135/775), for the female 13.6% (57/419), in upper jaw the male 19.3% (70/362), the female 17.5% (38/217), in lower jaw the male 13.7% (65/413), the female 9.4% (19/202). The sexual difference in the maxilla was hardly showed. In the appearance rate of the mandible the male was higher than the female, the rate was higher in the upper jaw than in the lower jaw through both sexes. 3. In the morphological abnormalities of the tooth crown, the giant teeth appeared only the male 0.3% (2/775), the microdont teeth the male 16.5% (128/775), the female 11.9% (50/419). Peg-shaped teeth appeared in the male 0.6% (5/775), in the female 1.7% (7/419). 4. The tooth of high frequency about morphological abnormalities was in the upper lateral incisors in both male and female subjects, the male 52.8% (28/53), the female 51.4% (19/37), after this the upper second premolar, the lower second premolar and the upper and lower first premolar.

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