著者
Nozomi SAITO Jaymee R. ENCABO Sunlu CHEN Gilda JONSON Yuji KISHIMA Il-Ryong CHOI
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.53, no.1, pp.1-6, 2019-01-01 (Released:2019-01-30)
参考文献数
25

Rice tungro disease (RTD) is a serious threat to rice production in South and Southeast Asia. RTD is caused by Rice tungro bacilliform virus (RTBV) and Rice tungro spherical virus (RTSV). Coinfection of RTSV and RTBV results in more severe symptoms in African rice Oryza glaberrima than in Asian rice O. sativa. In this study, we examined whether RTBV alone causes more severe symptoms in O. glaberrima than in O. sativa. The examination of 18 accessions of O. glaberrima for RTBV infection indicated that all the O. glaberrima accessions examined were susceptible to RTBV. The reactions to RTBV of three O. glaberrima accessions and two RTBV-susceptible varieties of O. sativa, Taichung Native 1 (TN1) and IR 64, were compared. RTBV accumulation varied depending on the plants and differences in RTBV accumulation were not evident between the two species. However, the O. glaberrima accessions were significantly more stunted by RTBV than IR 64 was. Discoloration of leaves by RTBV was evident in the O. glaberrima plants, but not in the O. sativa plants. Collectively, these results presumably indicated that O. glaberrima is generally more vulnerable to RTBV than O. sativa is.
著者
Mikio FUKUHARA Limi OKUSHIMA Kiyoshi MATSUO Tomoo HOMMA
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.39, no.1, pp.45-49, 2005-01-31 (Released:2014-02-27)
参考文献数
20
被引用文献数
4 7

The acoustic characteristics of sound fresh tea leaves were determined nondestructively by ultrasonic transmission analysis. As thickness increases, phase velocity and wavelength increase, and damping ratio and dynamic viscosity decrease, suggesting development of the fibrous tissues, accompanied by frequency convergence. The velocities of all the leaves studied were smaller than that of pure water. Decrease in viscoelasticity corresponds to increase in dynamic modulus. Thus, acoustically, we can regard the leaves as natural quasi-polymers with high viscoelasticity.
著者
Hideki HORIE Hidekazu ITO Katsunari IPPOUSHI Keiko AZUMA Yoshiteru SAKATA Isamu IGARASHI
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.41, no.1, pp.65-68, 2007 (Released:2013-03-26)
参考文献数
14
被引用文献数
19 21

Cucumber plants contain a bitter substance, cucurbitacin C. The compound was isolated from cucumber leaves using preparatory HPLC (high performance liquid chromatography) to investigate the relationship between its content and bitterness of the plant parts. An analytical method for cucurbitacin C using HPLC was also established. A Japanese popular cultivar, ‘Sharp 1’ contained the compound in the leaves but not in the fruits, while a unique cultivar with white skin ‘Shinsyo Hakuhi’ contained it both in leaves and fruits. The stem end of ‘Shinsyo Hakuhi’ fruit contained higher amounts of it than other fruit parts. Cucurbitacin C is a strongly bitter component and its threshold level was less than 0.1 mg/L. The bitter sensation felt when biting the plant parts could be interpreted as corresponding to the content of cucurbitacin C.
著者
Yoshiki KATO Toshiaki SHITAMITSU Makoto OKAZAKI Hideyuki YAMASHITA
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.57, no.2, pp.145-152, 2023-04-01 (Released:2023-04-26)
参考文献数
27

The neon flying squid, Ommastrephes bartramii, is an economically important oceanic squid species that has been harvested commercially in the North Pacific by Japan, Korea, China, and Taiwan. The Fisheries Research Agency (FRA) of Japan conducted long-term research for this species from 1980 to 2009 using commercial vessels to clarify the resource ecology and it obtained a total dataset of approximately 9,000 days, where following from this and to better clarify the relationship between habitat preference and oceanographic conditions, a generalized additive model was applied and mapped onto the Simple Ocean Data Assimilation ocean/sea ice reanalysis (SODA) data. The resultant habitat map of the squid showed an area of high abundance at the Subarctic Frontal Zone (SAFZ), with abundance areas increasing the squid abundance from April to August. The SAFZ extends from 40°N to 43°N separating the cold, low-salinity, subarctic water to the north from the waters of the North Pacific Transition Zone to the south. This high abundance area intersects between subarctic area and temperate area. It has characteristic nutrient regimes, productivity cycles, and nektonic faunal compositions. This paper suggests that the SAFZ thus plays an important role in North Pacific ecosystems by providing an optimal balance between environmental temperature and food density for the neon flying squid.
著者
Akinori MORI Yuma MICHINOBU Akira MIYATA Takehiko MATSUMOTO Shoji MATSUURA Mikinori TSUIKI Takatoshi ARITA Mariko SHIMIZU Ryusuke HATANO
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.56, no.4, pp.349-356, 2022-10-01 (Released:2022-11-05)
参考文献数
13

In 2015-2016, we investigated the farmland management procedures used on dairy farms in Japan using a mail-back survey. In Hokkaido, 98% of the surveyed farms had meadows, 53% had pastures, and 49% had forage crop fields. In all other prefectures, 19% of farms had meadows, 10% had pastures, and 90% had forage crop fields. The median area of each field category per farm was greater in Hokkaido than in the other prefectures. In all places, the application rate of organic fertilizer decreased in the following order: forage crop field > meadow > pasture (37, 8.7, and 2.7 Mg-manure ha−1 y−1, respectively, in Hokkaido). In forage crop fields, organic fertilizer was applied at lower rates and inorganic fertilizer was applied at higher rates in Hokkaido than elsewhere (37 vs. 69 Mg-manure ha−1 y−1 and 42 vs. 22 kg-N ha−1 y−1 respectively). In meadows, organic fertilizer was applied at lower rates in Hokkaido (8.7 vs. 14 Mg-manure ha−1 y−1); however, inorganic fertilizer was applied at similar rates. The annual rate of grassland renovation with full-inversion tillage in 2006-2010 was 3.0% in Hokkaido and 1.3% in the other prefectures. In both regions, manure was intensively applied during grassland renovation.
著者
Yumiko KURA Nozomi KAWARAZUKA
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.55, no.Special, pp.553-558, 2021-12-01 (Released:2022-02-10)
参考文献数
46
被引用文献数
1

Fisheries research and development challenges have diversified significantly as we entered the 21st century. The 2030 Agenda for Sustainable Development demands that agriculture research communities take more holistic approaches towards addressing global issues, such as poverty alleviation, environmental conservation, and food and nutrition security. There remains a growing need for considering both fisheries and fishing communities as part of social-ecological systems. In this paper, we review how over the last two decades WorldFish has framed its research, with an emphasis on small-scale fisheries in low- and middle-income countries, and the contribution Japanese researchers have made in topics relevant to the Sustainable Development Goals (SDGs): sustainable fisheries management and conservation; resource access and benefit-sharing; and food and nutrition security. Research in the past has shown collaborative forms of natural resource governance, social inclusion and gender equity play a critical role in ensuring food production translates to income and livelihoods outcomes, and to food and nutrition security in low- and middle-income country contexts. To fulfill its potential in a wider range of SDGs, future research needs to consider fisheries and aquaculture as an integral component of “food systems”, encompassing production systems, their environments, post-harvest value chains, and consumer behavior and diets.
著者
Norihito KANAMORI Miyuki IIYAMA
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.55, no.Special, pp.395-404, 2021-12-01 (Released:2022-02-10)
参考文献数
37

For the past 50 years, agricultural research has contributed significantly to improving agricultural productivity for global food and nutrition security. The CGIAR, formerly the Consultative Group for International Agricultural Research, has been at the center of this effort. Accordingly, the orientation of CGIAR activities have profoundly changed over time from crop productivity improvement to broadened agendas, such as biodiversity conservation, environmental protection, and policy-related efforts. In parallel with the evolution of research orientation, the CGIAR also underwent operational reorganization. As the global food systems become more and more interconnected, and with global concerns about agriculture’s contribution to overstepping the planetary boundaries and driving climate crises, the CGIAR has tried to consolidate operations among the CGIAR Research Centers to address research needs of smallholder farmers in the 21st century. This review contextualizes the evolving role of the CGIAR vis-à-vis global challenges with reference to some highlights of Japan’s contribution in each of the following periods: the 1970s; the 1980s-1990s; the 2000s-2010s; and onwards. This exercise can contribute to understanding the drivers affecting the global food systems in retrospective and subsequently deriving foresights for future directions of the food system transformation.
著者
Atsushi YAMASAKI
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.47, no.1, pp.37-42, 2013 (Released:2013-01-21)
参考文献数
36
被引用文献数
18 35

In Japan, more than 90% of strawberries are produced by forcing culture, which involves inducing flowering in autumn by several artificial methods (e.g. chilling, short-day), growing plants under a heated greenhouse to avoid the induction of dormancy and dwarfing, and keeping them in a semi-dormant state to allow continued harvesting. Although the normal harvest period is from late November to June, progress in technological research and the development of forcing has contributed to such long-term harvests. In forcing culture, it is important to understand the dormancy status of the strawberry plants, since controlling dormancy is key to realizing long-term successive harvests between winter and early summer. However, the last two decades have seen increasing demand for a year-round supply of strawberries for confectioners. Recent progress in the research and development of strawberry year-round production technology is reviewed with special reference to the activities of a summer-autumn production research team in the Tohoku region.
著者
Masayoshi NAKAYAMA
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.48, no.3, pp.271-277, 2014-07-01 (Released:2014-07-31)
参考文献数
31
被引用文献数
3 7

The coloration pattern of flower tissue affects the commercial potential of floricultural plants and is also a subject of fundamental biological interest. Transposon insertion or excision and post-transcriptional gene-silencing are well-studied mechanisms involved when flower color patterns form. In this paper, I present a research strategy to understand the mechanisms that govern the formation of flower color patterns. First, I discuss the significance of flower color pattern-formation research and then go on to describe a research system in the following six sections: Observation of flower patterns, Comparison of pigment components, Gene expression analysis, Regulation of target gene expression, Genomic structure, and Factors that can change color pattern-formation. In these sections, reference is made to my own studies on the marginal picotee pattern of Petunia flowers. Post-transcriptional gene-silencing of the chalcone synthase gene is responsible for the formation of white tissue in the white marginal picotee pattern in Petunia flowers. The unusual genomic structure of chalcone synthase is probably related to the operation of position-specific post-transcriptional gene-silencing. In the colored marginal picotee pattern of Petunia flowers, the higher expression of flavonol synthase is a responsible for the central white tissue formation. I also provide a research perspective from which to resolve the remaining questions.
著者
Taro IMAMURA Mika MURATA Akihiro MIYANOSHITA
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.42, no.1, pp.1-6, 2008 (Released:2013-03-26)
参考文献数
37
被引用文献数
6 13

The subject of this study was to examine biological aspects and predatory abilities of predatory bugs that prey on stored-product insects. Biological controls in stored products are being regarded with increasing interest since they are nontoxic and do not damage human health or the environment. Several species of predatory bugs have been studied as biological control agents. Specifically, Xylocoris flavipes (Reuter) is the most studied candidate biological control agent among predatory bugs. X. flavipes is advantageous because it has a high population increase capacity and wide distribution. X. flavipes has been reported to suppress populations of small insects, but it can not predate large insects and internal grain feeding insects. As Amphibolus venator (Klug), Peregrinator biannulipes (Montrouzier & Signoret) and Joppeicus paradoxus Puton can attack large insects, more research should be carried out on the suppression effects of these bugs. A combination of several biological control agents that can attack different types of insects will be needed to control whole pest complexes in various stored environments.
著者
Toshihiko SUGIURA Hirokazu SUMIDA Shigeki YOKOYAMA Hiroshi ONO
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.46, no.1, pp.7-13, 2012 (Released:2012-02-17)
参考文献数
32
被引用文献数
19 36

To determine the effects of recent warming trends on agricultural production in Japan, in 2003 and 2005, surveys of the public institutes of agricultural research in 47 prefectures were conducted. The results suggest that recent warming trends have already significantly affected nearly all types of crops and livestock in Japan. All 47 prefectures reported warming effects on fruit tree cultivation and over 70% of prefectures recognized the effects on rice, vegetable and flower cultivation. Horticultural crops and rice are likely to be more sensitive to global warming than other agricultural crops and livestock. Our survey elucidated many effects of recent warming, such as phenological changes in many crops, increases in fruit coloring disorders and incidences of chalky rice kernels, reductions in yields of wheat, barley, vegetables, flowers, milk and eggs, and alterations in the type of disease and pest.
著者
Yuko TAKADA HOSHINO Naoyuki MATSUMOTO
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.39, no.4, pp.247-252, 2005-10-31 (Released:2014-02-27)
参考文献数
29
被引用文献数
12 28

There is an increasing interest in the extraction of DNA from soil, since molecular techniques facilitate the analysis of the microbial community including unculturable microorganisms. Though various methods of direct DNA extraction have been devised, it still remains difficult to extract DNA from some soils. We developed an improved method to extract DNA from such “recalcitrant soils”. Andisol, volcanic ash soils are recalcitrant in this context. Skim milk increased the efficacy of DNA extraction from such soils, when added to the extraction buffer as an adsorption competitor to soil particles. This method is applicable to molecular community analysis of soils which strongly adsorb DNA.
著者
Akemi OHMIYA
出版者
Japan International Research Center for Agricultural Sciences
雑誌
Japan Agricultural Research Quarterly: JARQ (ISSN:00213551)
巻号頁・発行日
vol.45, no.2, pp.163-171, 2011 (Released:2012-01-19)
参考文献数
50
被引用文献数
19 61

Carotenoids are yellow, orange, and red pigments that are widely distributed in nature. In plants, carotenoids play important roles in photosynthesis and furnishing flowers and fruits with distinct colors. While most plant leaves show similar carotenoid profiles, containing carotenoids essential for photosynthesis, the carotenoid composition of flower petals varies from species to species. In this review, I present a list of carotenoid composition in the flower petals of various plants and discuss the possible causes of qualitative diversity.