Genome-Wide DNA Methylation Analysis Reveals Phytoestrogen Modification of Promoter Methylation Patterns during Embryonic Stem Cell Differentiation

BACKGROUND: Environmental challenges during development affect the fetal epigenome, but the period(s) vulnerable to epigenetic dysregulation is(are) not clear. By employing a soy phytoestrogen, genistein, that is known to alter the epigenetic states of the A(vy) allele during embryogenesis, we have explored the sensitive period for epigenetic regulation. The post-implantation period, when de novo DNA methylation actively proceeds, is amenable to in vitro analysis using a mouse embryonic stem (ES) cell differentiation system. METHODS AND FINDINGS: Mouse ES cells were differentiated in the presence or absence of genistein, and DNA methylation patterns on day 10 were compared by microarray-based promoter methylation analysis coupled with a methylation-sensitive endonuclease (HpaII/McrBC)-dependent enrichment procedure. Moderate changes in methylation levels were observed in a subset of promoters following genistein treatment. Detailed investigation of the Ucp1 and Sytl1 promoters further revealed that genistein does not affect de novo methylation occurring between day 0 and day 4, but interferes with subsequent regulatory processes and leads to a decrease in methylation level for both promoters. CONCLUSION: Genistein perturbed the methylation pattern of differentiated ES cells after de novo methylation. Our observations suggest that, for a subset of genes, regulation after de novo DNA methylation in the early embryo may be sensitive to genistein

Development and Practice of Introductory Teaching Materials for Science "Problem- Based Learning" on the Theme of "Removal of Roadside Utility Poles"

P(論文)平成29年～ 30年に改訂された学習指導要領においては，持続可能な開発のための教育（ESD）や主権者教育などが取り上げられている．本稿では，新・逆向き設計に基づき，SDGsに関連した政策の評価を「総合的な学習の時間」で生徒が取り組めるようにするため，各教科で行う探究活動の準備段階で用いるゲーミング教材について，特に理科の物理と生物の知識を活用する教材を開発した．教材は無電柱化の政策に関する評価を題材とし，学習した知識と関連付ける形で優先的に無電柱化に取り組む地域の優先度を検証する活動を通じて，探究活動の流れと探究における知識活用の方法論を学び今後取り組む探究活動や市民生活における理科の知識の活用の見通しを得ることを教材の目標とした．実践の結果，生徒は理科の知識の重要性を認識した一方，教材に関しては化学の知識活用の追加，時間配分の改善，定量的評価を用いた探究の導入の3 点の改善点があった．departmental bulletin pape

Effect of Nitrogen Application Timing on Growth, Grain Yield and Eating Quality of the KD18 and TH3-3 Rice Varieties

This study examined the effect of nitrogen application timing on growth characteristics and seed quality in inbred KD18 and hybrid TH3–3 rice varieties. A pot experiment was conducted in 2012 in a greenhouse at Kyushu University, Japan. The treatments were T0 (no nitrogen application), T1 (40:40:20), T2 (50:50:0), T3 (50:30:20), and T4 (50:20:30), with the ratios indicating the percentages of total nitrogen applied at the basal, active tillering, and panicle initiation stages. Tiller number and panicle number were highest in T2. The soil plant analysis development (SPAD) value was higher in T2 until the panicle initiation stage, after which it was higher in T4 for both varieties. KD18 produced more grain weight in T4 and T2, whereas TH3–3 produced the highest grain weight in T3. Late nitrogen application timing (T3 and T4) increased the starch and amylopectin content of the hybrid rice and the protein content of the inbred rice

Symbiotic effectiveness of different indigenous Bradyrhizobium strains on selected Rj-genes harboring Myanmar soybean cultivars

Many scientists are working to identify effective strains of rhizobia to increase nitrogen fixation and reduce nitrogen fertilizer application. Symbiotic nitrogen fixation of leguminous crops has become an alternative to nitrogenous fertilizer, due to its higher efficiency for nitrogen fixation. This experiment was conducted to select strains for improved nitrogen fixation of soybean (Glycine max L.). Bradyrhizobium strains isolated from Myanmar were evaluated for symbiotic efficacy, using the cultivar Yezin-6 (non-Rj). Five Bradyrhizobium strains, B. japonicum SAY3-7, B. elkanii AHY3-1, B. liaoningense SMY3-1, Bradyrhizobium spp. AHY3-6 and B. yuanmingense SMY6-10 were shown to have superior nitrogenase activity. These five strains were evaluated for their effectiveness on different Rj-genes in soybean cultivars. The nitrogen fixation of B. japonicum SAY3-7, B. elkanii AHY3-1 and B. liaoningense SMY3-1 were higher than other indigenous strains and the standard strain, B. japonicum USDA110. This was particularly the case for the cultivars Yezin-6 (non-Rj) and Yezin-11 (Rj4), but not for the cultivarsYezin-9 (Rj3) and Yezin-10 (Rj2Rj3). Bradyrhizobium japonicum SAY3-7, B. elkanii AHY3-1 and B. liaoningense SMY3-1 were also evaluated on Yezin-8 (non-Rj) and Yezin-3 (Rj4). Bradyrhizobium japonicum SAY3-7 had significantly higher nitrogenase activity on Yezin-8 (non-Rj), although B. japonicum SAY3-7 was not significantly different than B. elkanii AHY3-1 and B. liaoningense SMY3-1 on Yezin-3 (Rj4). Therefore, B. japonicum SAY3-7, which was the most effective nitrogen fixing strain in all the experiments, was selected for inoculant production. According to this study, it can be concluded that the strains were specific to cultivars and,thus, selection of a strain compatible to a specific cultivar is necessary to increase symbiotic nitrogen fixation

Combined Effect of Organic Manures and Inorganic Fertilizers on the Growth and Yield of Hybrid Rice (Palethwe-1)

We investigated the effect of combining organic and inorganic fertilizers on the growth and yield of hybrid rice (Palethwe-1) in the dry and wet seasons of 2015. Four quantities of inorganic fertilizer were used in the main plot [0%, 50%, 75%, and 100% nitrogen, phosphorus, and potassium (NPK)] based on the recommended amounts of 150 kg N ha−1, 70 kg P2O5 ha−1, and 120 kg K2O ha−1, while different organic manures were applied to subplots [no organic manure (O0), cow manure (Oc), poultry manure (Op), and vermicompost (Ov); all at 5 t·ha−1] as part of a split-plot experimental design with three replicates. In both seasons, significant differences in growth parameters including number of tillers hill−1, soil-plant analysis development (SPAD) values, total dry matter, yield, and yield components were observed in plants supplied with different inorganic fertilizers. The 100% NPK (I100) fertilizer produced the maximum yield but similar yields were achieved in plots supplied with 50% NPK (I50) and 75% NPK (I75). Significant differences in growth and yield parameters were also found in crops supplied with organic manures. Although identical quantities were supplied, Op produced the best growth parameters in both seasons including total dry matter, yield, and yield components. Oc also performed well. Combining inorganic and organic fertilizers demonstrated that I50 together with Op (5 t·ha−1) provided similar growth, total dry matter, and yield parameters to I100 in both seasons. Oc (5 t·ha−1) plus I75 also achieved similar yields to I100. This study demonstrates that the combined application of inorganic fertilizers and organic manures has the potential to reduce chemical fertilizer usage without decreasing the yield of hybrid rice, and can enhance the growth, yield, and yield components of Palethwe-1

Biofertilizer Production for Agronomic Application and Evaluation of Its Symbiotic Effectiveness in Soybeans

This study was conducted to evaluate the effects of Bradyrhizobium japonicum SAY3-7, Bradyrhizobium elkanii BLY3-8, and Streptomyces griseoflavus P4 on the symbiotic effectiveness of soybeans before biofertilizer production, to produce biofertilizer containing the studied three strains (SAY3-7, BLY3-8, and P4), to test the effectiveness of the biofertilizer on soybean varieties, and to assess the varietal effects and interaction effects between variety and biofertilizer on plant growth, nodulation, nitrogen fixation, nutrient absorption, and seed yield. Nitrogen fixation was measured using the acetylene reduction assay and ureide methods. Contents of nutrients (N, P, K, Ca, and Mg) were also measured to calculate their uptakes. In this study, synergistic effects of nitrogen fixation were induced by combined inoculation with SAY3-7, BLY3-8 and P4 in all tested soybean varieties. Therefore, we assumed that an effective biofertilizer could be produced using these effective bacteria (SAY3-7, BLY3-8, and P4). After making biofertilizer using these effective bacteria, packages were stored at 30 °C. The populations of the bacteria in the biofertilizer were maintained at a density of 1 × 108 colony forming units (cfu) g−1 for P4 and 7 × 109 cells g−1 for Bradyrhizobium. Diluting biofertilizer by 10−3 proved more effective for nodulation and nitrogen fixation than other dilution treatments. Moreover, this biofertilizer significantly promoted plant growth, nodulation, nitrogen fixation, nutrient uptakes, and seed yield in Yezin-3 and Yezin-6 soybean varieties. Yezin-6 is a more efficient variety than Yezin-3 for improved plant growth, nodulation, nitrogen fixation, nutrient absorption, and seed yield. Taken together, the application of an effective biofertilizer and the use of an efficient soybean variety can play important roles in promoting plant growth, nodulation, nitrogen fixation, and higher seed yield

Effects of Pretransplant Basal and Split Applications of Nitrogen on the Growth and Yield of Manawthukha Rice

A field experiment was conducted to investigate the effects of pretransplant basal (surface application, BSF, and incorporation methods, BIC) and split applications of nitrogen (N) on the growth and yield parameters of rice. Using 120 kg N ha−1 except (N0, control), different percentages of N rate were applied at basal, tillering, and panicle initiation in five N split treatments. Growth parameters and dry matter were greater in BIC than BSF until panicle initiation stages. Among N split applications, N2 (25:50:25) using low basal surface N was optimized for maximum dry matter and yield. With large incorporated basal N, N1 (50:25:25) obtained greater dry matter and yield but did not differ from N4 (50:50:0). With omitted N at tillering, N5 (50:0:50) did not increase rice yield or dry matter by either method. This study highlighted that N split-application patterns affect the growth and yield parameters of Manawthukha rice

Effects of Combined Application of Inorganic Fertilizer and Organic Manures on Nitrogen Use and Recovery Efficiencies of Hybrid Rice (Palethwe-1)

We conducted two field experiments to investigate combined effects of or- ganic and inorganic fertilizers on nitrogen use and recovery efficiencies of hybrid rice (Palethwe-1) during dry and wet seasons, 2015. Four levels of in- organic fertilizer (0%, 50%, 75%, and 100% NPK), based on recommended rates of 150 kg N ha−1, 70 kg P2O5 ha−1, and 120 kg K2O ha−1, were used with cow manure, poultry manure, and vermicompost (5 t•ha−1each) in a split-plot design with three replicates. In both seasons, with 50% NPK, the N uptake level achieved with poultry manure was similar to that obtained with 75% and 100% NPK. The greatest N use, internal, agronomic N use, and recovery effi- ciencies were obtained with 50% NPK + poultry manure, but were similar to those obtained from cow manure and vermicompost subplots. As the amount of applied N from organic and inorganic fertilizer increased, the N use effi- ciency and related parameters decreased, due to similar yields among plots with different NPK application levels. Poultry manure resulted in the highest significant correlations between applied N and N accumulation, followed by cow manure and vermicompost, in both seasons. Neither chemical fertilizer nor organic manure alone led to optimum N use and N recovery efficiencies. The combination of 50% inorganic fertilizer (75 kg N ha−1) and poultry ma- nure (5 t•ha−1) enhanced the N uptake, the N use and recovery efficiencies of hybrid rice. Cow manure (5 t•ha−1) in combination with 75% inorganic ferti- lizer (112.5 kg N ha−1) was an adequate substitute for reduced chemical ferti- lizer usage. Therefore, this study highlighted combined application of inorganic fertilizers and organic manures had the benefits not only in reducing the need for chemical fertilizers but also in improving N uptake by hybrid rice (Palethwe-1) leading to the better environment

NPK Accumulation and Use Efficiencies of Manawthukha Rice (Oryza sativa L.) Affected By Pretransplant Basal and Split Applications of Nitrogen

We investigated the effects of split applications of nitrogen (N) on N, phosphorus, and potassium (NPK) uptake and use efficiency of rice under basal surface-application and incorporation methods. Different amounts of N were applied at the basal, tillering, and panicle initiation stages in five N split treatments. Basal incorporation provided greater NPK uptake than basal surface application until initiation of the panicle. In basal surface application, N2 (25:50:25) resulted in the greatest total NPK uptake, use efficiency, and N recovery efficiency. In basal incorporation, N1 (50:25:25) resulted in greater values for all parameters. The N5 (50:0:50), which included omitting N at tillering, resulted in low N recovery efficiency and uptake, both under basal incorporation and basal surface application. These results emphasize that split applications of N influence N recovery efficiency and total NPK uptake and use efficiency of rice