Damping-off of soybean caused by Pythium myriotylum in Japan

Severe rotting and blight of seedlings of soybean, Glycine max (L.) Merr., were found in Hiroshima Prefecture in the southwest region of Japan in July 2009. A filamentous microorganism, isolated repeatedly from the diseased seedlings and identified as Pythium myriotylum, was demonstrated to be pathogenic to seedlings of soybean. The disease was new in Japan, and we propose to include this oomycete as one of the pathogens causing damping-off of soybean.     

Nitrogen Isotope Study on Nitrate-Contaminated Groundwater in the Sichuan Basin, China

We investigated the expansion of NO₃ ^?-contaminated groundwater in the Sichuan Basin, China. Nitrogen concentrations and isotopic ratios of NH₄ ⁺ and NO₃ ^? were analyzed in groundwater and rain collected from four areas in this basin in order to evaluate the sources of nitrogen pollution. NH₄ ⁺ in rain, for which δ¹⁵N values are strongly negative to slightly positive ?13.4 to + 2.3‰, appears to originate from fertilizers and excretory waste. NO₃ ^? in rain (δ¹⁵N: ?10.2 to ?4.4‰) was attributed to NO _x from automobile exhaust gas. In the studied area, well water sampled from farmyards was found to have the highest δ¹⁵N_NO3 (average: +9.7 ± 4.7‰), indicating contamination by domestic sewage as animal excrement. The lowest δ¹⁵N_NO3 (?0.2 ± 3.7‰), found in spring water, indicates that the studied groundwater samples are widely affected by air contaminants (mainly as nitrogen oxides) resulted from fuel combustions. The δ¹⁵N_NO3 (+3.7 ± 2.1‰) values of well water from farmland are between these levels, suggesting that NO₃ ^? contamination results primarily from cultivation using nitrogen fertilizers, although the contribution from animal excrement cannot be excluded. These results demonstrate that the studied groundwater is widely polluted by locally derived nitrogen sources.     

Simultaneous determination of Angiotensin I-converting enzyme inhibitory peptides in tryptic casein hydrolysate by high-performance liquid chromatography combined with a replicate heart-cut column-switching technique

A replicate heart-cut column-switching HPLC method combined with two switching valves was newly developed for the simultaneous determination of three antihypertensive peptides (Ala-Phe, Tyr-Pro, and Trp-Tyr) in tryptic casein hydrolysate in one run-in assay. After a first separation on an octadecyl silane (ODS) column, heart-cuts of each peptide were individually separated on a subsequent analytical ODS column: 26% acetonitrile for Ala-Phe and Tyr-Pro (32% for Trp-Tyr) in 0.1% trifluoroacetic acid containing 10 mM sodium 1-octanesulfonate at 0.8 mL/min. Ala-Phe, Tyr-Pro, and Trp-Tyr in casein hydrolysate were determined within 70 min to be 0.377 +/- 0.037 mg/g, 2.50 +/- 0.26 mg/g, and 0.096 +/- 0.008 mg/g, respectively.     

Spontaneous iron accumulation in hepatocytes of a 7-week-old female rat

Spontaneous iron accumulation in hepatocytes was observed in a 7-week-old female Han Wistar GALAS rat. Very fine yellowish brown pigments, which showed a positive reaction with Berlin Blue stain, were apparent in the cytoplasm close to the bile canaliculi, with a diminishing periportal-to-centrilobular gradient. There were also differences in distribution between and within lobes. Transmission electron microscopy revealed cytosolic ferritin and pericanalicular siderosomes in hepatocytes. No degeneration or necrotic changes were observed, and non-hepatocyte cells did not demonstrate any obvious accumulation of iron. There were no abnormalities in the animal other than this finding in the liver.     

No Modifying Effect of Antioxidant N-Acetyl-L-Cysteine on Fenofibrate-induced Hepatocarcinogenesis in Rats

To clarify the modifying effect of N-Acetyl-L-Cysteine (NAC), which has antioxidative ability, on hepatocarcinogenesis promoted by fenofibrate (FF), a peroxisome proliferator-activated receptor (PPAR) alpha agonist , male F344/N rats were administered a single intraperitoneal injection of N-diethylnitrosamine (DEN) as an initiator followed by administration of a diet containing 3,000 ppm of FF for 16 weeks. Two-thirds partial hepatectomy was performed 1 week after the FF treatment. Additionally, NAC treatments for 14 weeks from 2 weeks after the FF treatment were performed. Although the expression level of tumor protein p53 (Tp53) mRNA decreased in the DEN+FF+NAC group as compared with that in the DEN+FF group, no significant differences between the DEN+FF and DEN+FF+NAC groups were observed in the number of hepatocellular altered foci and activities of hepatocellular proliferation. In addition, the results of an antioxidant enzyme assay and measurement of the amounts of total glutathione in the liver revealed no significant difference between the DEN+FF and DEN+FF+NAC groups; although no significant differences were observed in many genes between the DEN+FF and DEN+FF+NAC groups, only glutathione peroxidase 2 (Gpx2) mRNA increased in the DEN+FF+NAC group as compared with the DEN+FF group. The results under the present experimental conditions indicate no obvious modifying effect of NAC on liver tumor promotion by FF in rats.     

Manure application has an effect on the carbon budget of a managed grassland in southern Hokkaido,Japan

Abstract

The carbon (C) budget of managed grassland in a cool-temperate region of Japan was estimated using a combination of eddy covariance and the biometric method for five years, to evaluate the effect of manure application. Chemical fertilizer was applied to the fertilizer (F) plot at a rate of 79 ± 20 kg N ha^?1 yr^?1. In the manure (M) plot, dairy cattle manure was applied at a rate of 10 Mg fresh matter ha^?1 yr^?1 (1923 ± 407 kg C ha^?1 yr^?1, 159 ± 68 kg N ha^?1 yr^?1). There was no significant difference in seasonal gross primary production (GPP) and harvest between the treatment plots, indicating that both fertilizer and manure can increase the biomass production. Annual net ecosystem production (NEP) and ecosystem respiration (RE) was significantly different between the treatment plots. The difference in RE, and between M and F plots approximates heterotrophic respiration of manure (RHm), which ranged from 0.9 to 1.3 Mg C ha^?1 yr^?1. Average annual RHm was 1.1 ± 0.4 Mg C ha^?1 yr^?1, and accounted for 56% of the total amount of applied manure C. The annual net biome production (NBP) in the M plot (from 0.0 to 1.5 Mg C ha^?1 yr^?1) was significantly higher than in the F plot (?1.4 to 0.5 Mg C ha^?1 yr^?1). The long-term effect of manure application combined with chemical fertilizer did not reduce grass production compared with chemical fertilizer only; however, manure application decreased the NEP throughout manure decomposition, and long-term manure application enhanced the NBP.     

Yield and dry matter dynamics of vegetative and reproductive organs in Japanese and US soybean cultivars

ABSTRACT

Recently, US soybean cultivars have exhibited higher yields than Japanese soybean cultivars. To identify the determinants for this yield difference in reference to dry matter dynamics, recently developed US cultivars and Japanese commercial cultivars were cultivated in drained paddy fields in 2012 and 2013. The total dry matter (TDM) of each cultivar was measured at the initial seed-filling stage (R5), at 30 d after R5, and at maturity (R8). From R5 to R8, the DM of abscised leaves and petioles were measured. The actual HI (with abscised leaves and petioles) and apparent HI (without abscised leaves and petioles) were determined at R8. US soybean cultivars showed higher yields and apparent TDM (without abscised leaves and petioles) than did Japanese cultivars at R8. However, the difference in actual TDM (with abscised leaves and petioles) production was not significant between US and Japanese cultivars at R8. On the other hand, the actual HI was higher in US cultivars than in Japanese cultivars. US cultivars exhibited a higher TDM distribution to the pod before R5 and a higher pod growth rate from R5 to 30 d after R5. US cultivars tended to show greater crop growth rates (CGRs) from R5 to 30 d after R5. The higher yield in US cultivars was associated with the higher actual HI, which was considered attributable to a greater TDM productivity during the seed-filling period and higher DM distribution in the pod before R5.     

On the mechanical interaction between cellulose microfibrils and matrix substances in wood cell walls: effects of chemical pretreatment and subsequent repeated dry-and-wet treatment

We investigated the influences of chemical pretreatments and subsequent repeated dry-and-wet (RDW) treatments on the mechanical linkage between cellulose microfibrils (CMFs) and matrix substances (MT) in wood cell wall. Sugi (Cryptomeria japonica D. Don) quarter-sawn specimens were subjected to various types of chemical pretreatments, including ethanol and benzene extraction, delignification, alkali extraction, and hygrothermal treatment, to give substantial damages to principal constituents of wood cell wall, followed by 5 times of RDW treatment. After giving chemical pretreatment, the d-spacing of (200) lattice plane of cellulose I_β (d ₂₀₀), the crystallinity of wood cell wall, and the crystal size of the cellulose were measured at the fiber saturated point, using X-ray diffraction techniques. Thereafter, these were measured again at the absolutely dried condition in the process of subsequent RDW treatments. The d ₂₀₀ in specimens, which were given to light pretreatments, largely expanded by drying at the early stages of RDW treatments, then it decreased and became constant after 5 times of RDW treatments. On the other hand, d ₂₀₀ in specimens, which were given to intensive pretreatments, remained constant at a relatively small level throughout the whole process of RDW treatments. After 5 times of RDW treatments, d ₂₀₀ became similar values between the above two groups. This suggests that RDW treatments have similar effects as intensive pretreatments, which induce substantial damages to the microscopic region in the wood cell wall such as interfacial separation between CMF, MT, and so forth. These defects would weaken mechanical interaction between CMF and MT in the wood cell wall during drying.     

Pollution attenuation by roadside greenbelt in and around urban areas

Greenbelts are effective tools for mitigation of traffic induced air and noise pollution. In this study, the potential role of greenbelts along the roadside for the reduction of air pollution and noise levels has been assessed by using seasonally monitored data in a megacity of Bangladesh. Correlation analysis was performed between the vegetation status, measured by canopy density and shelterbelt porosity, and the total suspended particles (TSP) removal percentage. Further, the reduction of noise level was also analyzed. The results showed that the greenbelts greatly contributed to reduce TSP pollution and it was as much as 65%. Noise level reduction was also achieved up to 17 dB when compared to the open area. Moreover, TSP removal percentage was correlated to the crown density. Area having higher crown density demonstrated less air pollution and lower level of noise compared to the area having lower crown density. Greenbelt showed better performance in summer time than winter.     

Calculation of CFP and verification of effect on CO2 emission reduction for the use of certified wood in Kyoto Prefecture

The representative carbon footprint of product (CFP) value of “certified wood in Kyoto Prefecture” was calculated as 241?kg-CO₂/m³. The CFP value was 158?kg-CO₂/m³ when wood was not kiln dried and final processing was not involved, whereas that of “kiln-dried, finished wood” was 284?kg-CO₂/m³. Comparisons of different types of wood were also conducted to examine CO₂ emission-reducing effects of “certified wood in Kyoto Prefecture”. We compared the CFP of lumber produced (in Japan) from logs supplied from Japan and other countries and that of “certified wood in Kyoto Prefecture”; the lumber products as a target for comparison are shipped to markets throughout the country. The CFP of “certified wood in Kyoto Prefecture” was approximately 50% lower compared to that of North American wood lumbered in Japan and shipped to markets throughout the country, and about 30% lower compared to the mean CFP of lumber produced (in Japan) from logs supplied from Japan and other countries and shipped to markets throughout the country. We then compared the CFP of “products imported from other countries after being cut into lumber” to that of “certified wood in Kyoto Prefecture”. The CFPs of lumber products from North America and Europe were lower than that of “certified wood in Kyoto Prefecture” (kiln-dried, finished wood). However, when only woodchips were used as a heat source in the process of kiln drying, the CFP of “certified wood in Kyoto Prefecture” was lower than any other kiln-dried lumber products. Regarding “certified wood in Kyoto Prefecture”, the use of woodchips as a heat source in the process of kiln drying or a shift to air drying decreases the CFP.