| FullText URL | bfsc_042_pre.pdf |
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| Author | 齊藤 邦行| |
| Publication Title | Bulletin of the Field Science Center, Faculty of Agriculture, Okayama University |
| Published Date | 2020-04-01 |
| Volume | volume42 |
| Start Page | i |
| End Page | i |
| ISSN | 0910-8742 |
| language | Japanese |
| Copyright Holders | 岡山大学農学部 |
| File Version | publisher |
| Title Alternative | Comparisons of nitrogen use efficiency between rice cv. Nipponbare and Takanari at different fertilization levels |
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| FullText URL | srfa_113_033_039.pdf |
| Author | Saitoh, Kuniyuki| Danno, Yusuke| |
| Abstract | The rice cultivar Nipponbare and the high-yielding cultivar Takanari were cultivated in field trials for three years from 2003, and in pot trials (1/2,000a) for two years from 2004. In the field trials, the following three levels of fertilizer were applied：“0N” without fertilizer, “1N” with the standard amount(8kgN 10a–1), and “2N” with twice the standard amount (16kgN 10a–1). In the pot trial, three levels of fertilizer were applied：“0N” without fertilizer, “1.5N” with 1.5times the standard amount (1.5gN pot–1), and “3N” with three times the standard amount (3gN pot–1). In the field trials, yields were higher in Takanari (538 to 843g m–2) than in Nihonbare (423 to 577g m–2), and the increase in yield with fertilizer application was also larger in Takanari. This was related to the larger sink capacity of Takanari and the smaller decrease in the percentage of filled grain with larger sink capacity. The dry matter weight and nitrogen uptake at the panicle initiation stage were higher in the plots with higher fertilizer application, but the differences between the cultivars were small. Dry matter weight and nitrogen uptake at harvest time were higher in Takanari, and nitrogen use efficiency and sink production efficiency were also higher in Takanari, but the differences in nitrogen use efficiency between cultivars became smaller with increasing fertilizer application. The nitrogen use efficiency for dry matter production also decreased with increasing fertilizer application, and was higher in 2005 in Takanari. The leaf photosynthetic rate of Takanari was higher than that of Nipponbare in the pot experiment. The difference in leaf photosynthetic rate was related to the nitrogen use efficiency (photosynthetic rate / leaf nitrogen content), and the difference in leaf nitrogen content between cultivars was small. The nitrogen use efficiency for dry matter was highest in the “0N” and decreased with increasing fertilizer application, and was higher in Takanari than in Nipponbare. This was presumably related to the higher nitrogen use efficiency of photosynthesis. It was found that fertilizer application decreased nitrogen use efficiency and sink production efficiency, but yield increased with increasing sink capacity, and that differences in nitrogen use efficiency among cultivars were related to the amount of nitrogen absorbed up to the panicle initiation stage and sink production efficiency. In order to improve the efficiency of fertilizer application, it is desirable to increase nitrogen absorption, which is expressed as multiplying the number of days to panicle initiation and the rate of nitrogen absorption, and to select cultivars with higher sink production efficiency. |
| Keywords | High-yielding rice cultivar Nitrogen use efficiency Nitrogen uptake Sink capacity Sink production efficiency |
| Publication Title | Scientific Reports of the Faculty of Agriculture, Okayama University |
| Published Date | 2024-02-01 |
| Volume | volume113 |
| Start Page | 33 |
| End Page | 39 |
| ISSN | 2186-7755 |
| language | Japanese |
| File Version | publisher |
| Title Alternative | アメリカ産ダイズ品種‘UA4805’ の多収性に関する解析的研究－日本品種 ‘あきまろ’ との比較－ |
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| FullText URL | srfa_113_025_032.pdf |
| Author | Marouf, Sultanzada Mohammad| Hasegawa, Yu| Manabe, Ryuta| Saitoh, Kuniyuki| |
| Abstract | Field experiments were conducted in 2020 and 2021 at the Field Science Center of Okayama Univ. (34°41’ N, 133°55’ E). Two Soybean cultivars ‘UA4805’ and ‘Akimaro’ were sown with two planting densities, 12.5plants m−2 (sparse, 80×10cm) and 25plants m−2 (dense, 80×5cm)on May 25 (early), June 29 (normal), and Aug. 3 (late) in 2020, and 80 and 30cm row-width, and 12.5 and 25 plant m−2 in 2021 on June 23. Seed yield was higher in ‘UA4805’ than in ‘Akimaro’ in 2020 and 2021. The later the sowing time, the higher the seeds/stem ratio. Both cultivars showed higher dry matter in dense planting. Dry matter was higher in ‘Akimaro’, while seed yield was lower than ‘UA4805’. In contrast, ‘UA4805’ showed lower dry matter with higher seed yield. The numbers of nodes, pods, and seeds were higher in ‘UA4805’ resulting in the higher seed yield. Lodging score is larger in ‘Akimaro’ especially in dense planting. The seeds/stem ratio is much higher in ‘UA4805’ than ‘Akimaro’ across 2 densities, 3 sowing times and 2 row width. Pods setting ratio was nearly two times higher in ‘UA4805’ compared to ‘Akimaro’. The greater seed yield of ‘UA4805’ compared to ‘Akimaro’ was due to the higher pod setting ratio, seeds/stem ratio, and lower lodging score, nevertheless the dry matter was larger in ‘Akimaro’. If late sowing is applied, higher planting density is recommended for better seed yield. Narrow row is an effective way to improve seed yield in soybean. |
| Keywords | Narrow row Planting density Podding rate Seeds/stem ratio Seed yield Sowing time Soybean |
| Publication Title | Scientific Reports of the Faculty of Agriculture, Okayama University |
| Published Date | 2024-02-01 |
| Volume | volume113 |
| Start Page | 25 |
| End Page | 32 |
| ISSN | 2186-7755 |
| language | English |
| File Version | publisher |
| Title Alternative | Cultivar differences in nitrogen use efficiency of rice |
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| FullText URL | srfa_113_017_024.pdf |
| Author | Saitoh, Kuniyuki| Iwame, Yoshifumi| Maekawa, Masahiko| Takeda, Kazuyoshi| |
| Abstract | We investigated the effects of fertilizer-free and fertilizer-applied cultivation on growth, yield and nitrogen (N) utilization of rice cultivars in our Kurashiki paddy fields (Institute of Plant Science and Resources, Okayama Univ.), which have been cultivated without fertilizer since 1970, and also in our Okayama paddy fields, which are conventionally cultivated. In 2001, the cultivars Nipponbare (NIP) and Nourin 18 (N18) were cultivated in the Kurashiki fields, with a “0N plot” (no fertilizer application), a “1N plot” (standard fertilizer application), and a “2N plot” (double fertilizer application). In 2002, five cultivars were grown without fertilizer in the Kurashiki fields, and 51cultivars were tested in 0N and 1N plots in the Okayama fields. Yield (2001) in the Kurashiki fields was higher in the 0N plot for N18 (379g m–2), which had a higher number of spikelets per m2, than NIP (300 g m–2), while in the 1N and 2N plots it was higher for NIP, which had a higher percentage of ripening, and N18 had high yield potential even without fertilizer application, but low fertilizer tolerance. The differences in yield were related to N-uptake (NU), and the differences in N use efficiency (NUE, yield/NU) between cultivars were small. The pot experiment showed that the yield of 0N plot was higher for N18 than NIP grown in Kurashiki soil because of the higher number of spikelets per hill, and the yield in the Okayama soil was higher than that in the Kurashiki soil. Long-term non-fertilized soils are of poor soil fertility, which also decreases the NUE, and the NUE of N18 is higher than that of NIP under isolated conditions. The difference in yields is closely related to sink capacity (SC). In 2002, yields in the Kurashiki fields were highest in Takanari (TAK, 494g m–2) and lowest in NIP (350g m–2), and differences in yields were closely related to SC. NUE was highest in TAK (68.6) and lowest in Akebono (48.1). TAK had high NUE and high sink production efficiency (SPE, SC/NU), while N18 had low NUE but high SC due to higher NU, ensuring high yield even under unfertilized cultivation. Yields in the 0N and 1N plots cultivated in 2002 varied between 244–631g m–2 and 199–769g m–2, respectively. A close positive correlation was observed between yield and SC, and between NU and SC, suggesting that the SC through NU is involved in determining yield. A positive correlation was also observed between NUE and yield. It was found that yield increased with an increase in NUE, and that NUE decreased although yield increased with fertilizer application. Through selection of cultivars with high SPE, it is expected that it will be possible to breed low-input, high-yielding cultivars with high NUE in the future. |
| Keywords | High-yielding rice cultivar Nitrogen use efficiency Nitrogen uptake Sink capacity Sink production efficiency Unfertilized paddy field |
| Publication Title | Scientific Reports of the Faculty of Agriculture, Okayama University |
| Published Date | 2024-02-01 |
| Volume | volume113 |
| Start Page | 17 |
| End Page | 24 |
| ISSN | 2186-7755 |
| language | Japanese |
| File Version | publisher |
| FullText URL | srfa_109_013_020.pdf |
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| Author | Nguyen Quang Co| Nguyen Thi Thanh Hien| Saitoh, Kuniyuki| |
| Abstract | The field study was conducted in Nam Dong district, Thua Thien Hue province, Vietnam during May 2019 to observe the effects of SRI method on the rice yield and eradicate the factor affecting the yield. The study was carried out to evaluate the agronomic characteristics of rice, fresh and dry matter production, soil characteristics with a focus group discussion regarding cultivation by SRI and non-SRI methods. The soil analyses using standard measurements showed quite similar soil fertility in both SRI and non-SRI methods, while rice plants showed good agronomic performances and fresh and dry matter production in SRI method. At harvesting time, the yield and yield potentials of rice were greater in SRI than that in non-SRI methods. Focus group discussion found some factors that limited SRI development in Nam Dong district. |
| Keywords | Actual yield Focus group discussion Filled spikelets SRI Weeding |
| Publication Title | Scientific Reports of the Faculty of Agriculture, Okayama University |
| Published Date | 2020-02-01 |
| Volume | volume109 |
| Start Page | 13 |
| End Page | 20 |
| ISSN | 2186-7755 |
| language | English |
| File Version | publisher |
| Author | Tran LocThuya| Saitoh, Kuniyuki| |
|---|---|
| Published Date | 2017-02-01 |
| Publication Title | Scientific Reports of the Faculty of Agriculture, Okayama University |
| Volume | volume106 |
| Content Type | Departmental Bulletin Paper |
| Author | 出江 嘉朗| Saitoh, Kuniyuki| |
|---|---|
| Published Date | 2016-04-01 |
| Publication Title | Bulletin of the Field Science Center, Faculty of Agriculture, Okayama University |
| Volume | volume38 |
| Content Type | Departmental Bulletin Paper |
| Author | 齊藤 邦行| |
|---|---|
| Published Date | 2015-04-01 |
| Publication Title | 岡山大学農学部センター報告 |
| Volume | volume37 |
| Content Type | Others |
| Author | 齊藤 邦行| |
|---|---|
| Published Date | 2014-04-01 |
| Publication Title | 岡山大学農学部センター報告 |
| Volume | volume36 |
| Content Type | Others |
| Author | Yabe, Ryo| Nguyen Quang Co| Trinh Thi Sen| Saitoh, Kuniyuki| |
|---|---|
| Published Date | 2015-02-01 |
| Publication Title | 岡山大学農学部学術報告 |
| Volume | volume104 |
| Content Type | Departmental Bulletin Paper |
| Author | 田邊 詩步| 齊藤 邦行| 山内 稔| |
|---|---|
| Published Date | 2013-04-01 |
| Publication Title | 岡山大学農学部センター報告 |
| Volume | volume35 |
| Content Type | Departmental Bulletin Paper |
| Author | 齊藤 邦行| |
|---|---|
| Published Date | 2013-04-01 |
| Publication Title | 岡山大学農学部センター報告 |
| Volume | volume35 |
| Content Type | Others |
| Author | 齊藤 邦行| |
|---|---|
| Published Date | 2012-04-01 |
| Publication Title | 岡山大学農学部センター報告 |
| Volume | volume34 |
| Content Type | Others |
| Author | Ishizuki, Yuuki| Saitoh, Kuniyuki| |
|---|---|
| Published Date | 2012-02-01 |
| Publication Title | 岡山大学農学部学術報告 |
| Volume | volume101 |
| Content Type | Departmental Bulletin Paper |
| Author | 齊藤 邦行| 佐藤 貴之| 黒田 俊郎| |
|---|---|
| Published Date | 1996-12-27 |
| Publication Title | 岡山大学農学部農場報告 |
| Volume | volume19 |
| Content Type | Departmental Bulletin Paper |
| Author | Saitou, Kuniyuki| 多田 正人| 沼野 義和| 小林 恭子| Sen Trinh Thi| |
|---|---|
| Published Date | 2009-04-01 |
| Publication Title | 岡山大学農学部センター報告 |
| Volume | volume31 |
| Content Type | Departmental Bulletin Paper |
| Author | Oh-e, Izumi| Kobayashi, Yasuko| Saitoh, Kuniyuki| Kuroda, Toshiro| |
|---|---|
| Published Date | 2008-02 |
| Publication Title | 岡山大学農学部学術報告 |
| Volume | volume97 |
| Issue | issue1 |
| Content Type | Departmental Bulletin Paper |
| Author | Mahmood, Tariq| Saitoh, Kuniyuki| Kuroda, Toshiro| |
|---|---|
| Published Date | 1999-02 |
| Publication Title | 岡山大学農学部学術報告 |
| Volume | volume88 |
| Issue | issue1 |
| Content Type | Departmental Bulletin Paper |
| Author | Yamamoto, Ema| Matsue, Yuji| Saitoh, Kuniyuki| Kuroda, Toshiro| |
|---|---|
| Published Date | 2004-02 |
| Publication Title | 岡山大学農学部学術報告 |
| Volume | volume93 |
| Issue | issue1 |
| Content Type | Departmental Bulletin Paper |
| Author | Oh-e, Izumi| Matsue, Yuji| Saitoh, Kuniyuki| Kuroda, Toshiro| |
|---|---|
| Published Date | 2007-02 |
| Publication Title | 岡山大学農学部学術報告 |
| Volume | volume96 |
| Issue | issue1 |
| Content Type | Departmental Bulletin Paper |
