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

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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

Hironori KATO Akihiro INAGI Nozomi SAITO Phyo Thet Thet HTUN

出版者

Eastern Asia Society for Transportation Studies

雑誌

Journal of the Eastern Asia Society for Transportation Studies (ISSN:18811124)

巻号頁・発行日

vol.9, pp.914-929, 2011 (Released:2011-10-31)

参考文献数

19

被引用文献数

1

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This paper analyzes the feasibility of introducing a bus rapid transit (BRT) system and the restructuring of the bus route network to improve the performance of the local bus service in Yangon, Myanmar. First, we summarize the characteristics of the current urban bus service in Yangon. We point out that the point-to-point bus route network results in many overlapping routes along main roads and this leads to serious traffic congestion. Then, we examine the feasibility of two policy options. The first case (Case 1) introduces a new BRT line to the existing bus network; while the second case (Case 2) restructures the bus route network whilst introducing a new BRT line. Five types of BRT fares are considered for each case. To evaluate these policy options, a travel demand forecast system, including the estimation of an origin-destination table and a bus route-choice model, is developed. The results of the evaluation show that Case 1-400, in which a new BRT with a flat fare of 400 Kyats, introduced to the existing bus route network offers the most desirable outcome.