Relationships of culm surface area to other culm dimensions for bamboo, Phyllostachys pubescens

We determine the relationships of culm surface area to other culm dimensions for one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houzeau de Lehaie. A total number of 150 sample culms were collected from a stand of P. pubescens in Mt. Toshima, Kumamoto Prefecture, western Japan. The culm surface area for each sample was calculated, and then the relationships of the culm surface area to basal area and product of diameter at breast height (dbh) and culm height were analyzed. The relationship between culm surface area and basal area could be described successfully by the power equation, whereas there was a linear relationship of culm surface area to product of dbh and height. Although the regression equations determined here would be useful in estimating culm surface area of P. pubescens, it is necessary to select an appropriate equation depending on the purpose and available time and labor.     

Distribution and stem growth patterns of mangrove species along the Nakara River in Iriomote Island, Southwestern Japan

We examined variations in stand structure and tree growth of a mangrove forest along two gradients: from the river mouth to upper stream and from the riverside to inland, along the Nakara River, Iriomote Island, Japan. Bruguiera gymnorrhiza (L.) Lamk. occurred throughout the intertidal area, though Rhizophora stylosa Griff. and Kandelia candel (L) Druce did not occur upstream. Basal area and maximum tree height of B. gymnorrhiza decreased downstream. The growth rate in stem diameter of B. gymnorrhiza decreased downstream in relation with the soil salinity. The basal area and the maximum tree height of B. gymnorrhiza increased with the distance from the riverside. R. stylosa increased in stem diameter and growth rate toward the riverside.     

Rapid HPLC Method for Determination of 12 Isoflavone Components in Soybean Seeds

It is important to determine the isoflavone components by high-performance liquid chromatography(HPLC)for the molecular assistant selection of isoflavone in soybean.Based on the standard samples of 12 isoflavone components,the isoflavone components were analyzed using the determination of absorbance peaks method by HPLC.The results showed that there were different maximum ultraviolet(UV)absorbance for the aglycones of daidzein,glycitein,and genistein,which were at 250,257,and 260 nm,respectively.A linear gradient elution of acetonitrile(13-30%)containing 0.1% acetic acid as a mobile phase was applied on a YMC-C18 column at 35℃.The 12 isoflavone components were determined using the UV detector by HPLC.We concluded that this is a rapid and precise method which adapted to determine the large numbers of samples with microanalysis.     

‘Niigata S3’ is a new strawberry cultivar suitable for forcing culture under low temperature and insolation conditions

‘Niigata S3’ is a new strawberry (Fragaria × ananassa Duch.) cultivar that is early flowering and possesses high soluble solid content and good coloration. It was selected from a cross between Kei812 (seed parent) and ‘Asuka-Ruby’ (pollen parent). The first harvest date of ‘Niigata S3’ was December 27, 34 days earlier than ‘Echigohime’ and 9 days earlier than ‘Asuka-Ruby’ (means of 2007 and 2008). The marketable yield of ‘Niigata S3’ was 85% of ‘Echigohime’, 107% of ‘Asuka-Ruby’, while the early yield was 145% of ‘Echigohime’, 85% of ‘Asuka-Ruby’ (based on 2007 and 2008 means). The shape of the fruit is long conical, and its skin color medium-red. The fruit skin hardness of ‘Niigata S3’ was 31.5 g/mm², which was harder than ‘Echigohime’, and its average soluble solid content was 11.4%, which was higher than the values for ‘Echigohime’ and ‘Asuka-Ruby’ (2008). Furthermore, ‘Niigata S3’ did not bear apical overripe fruit. This new cultivar is adaptable to the climatic conditions of Niigata, as well as other regions that experience low winter temperatures and insolation.     

Effects of concanamycins produced by <Emphasis Type="Italic">Streptomyces scabies</Emphasis> on lesion type of common scab of potato

Streptomyces scabies, causative agent of common scab of potato, produces the phytotoxins concanamycin and thaxtomin. In a potato tuber slice assay to study the contribution of concanamycins to lesion development, concanamycin A had weak necrosis-inducing activities; >10× the amount of thaxtomin A was needed to produce equivalent lesion severity. Concanamycins were detected in tubers inoculated with S. scabies, which caused deep-pitted lesions but not in those inoculated with Streptomyces acidiscabies, which caused corky, raised lesions. In field-grown, diseased potatoes, concanamycin content tended to be higher in tubers with deep-pitted lesions than in those with corky, raised lesions.     

Evaluation of drag coefficients of poplar-tree crowns by a field test method

To estimate the wind force that causes windthrow damage to a tree, the drag coefficients of actual-sized trees were evaluated by a field test method. In this method, wind velocity and stem deflection were monitored simultaneously. The wind force acting on a tree crown was calculated from stem deflection; stem stiffness was evaluated by conducting tree-bending tests. The results of tests conducted on three poplar trees showed that drag coefficient decreased with an increase in wind velocity. Although the variation in the drag coefficient was large at low wind velocity because of the vibrating behavior of the stem subjected to variable wind force, the variation at wind velocities above 10 m/s was small. The average drag coefficient at a wind velocity of 30 m/s was estimated by the curve-fitting of a power function to the wind velocity-drag coefficient relationship to be 0.102, which was smaller than that of actual-sized conifers studied in previous wind tunnel experiments. The drag coefficients of these crown areas in the defoliation season were smaller than those measured in the leafy season.     

A 90-day Feeding Toxicity Study of l-Serine in Male and Female Fischer 344 Rats

A subchronic feeding study of l-serine (l-Ser) was conducted with groups of 10 male and 10 female Fischer 344 rats fed a powder diet containing 0, 0.06, 0.5, 1.5 or 5.0% concentrations of l-Ser for 90 days. There were no toxicologically significant, treatment-related changes with regards to body weight, food intake, water intake or urinalysis data. In several of the hematology, serum biochemistry and organ weight parameters, significant changes were observed between some of the treated groups and the controls. All these changes, however, were subtle and lacked any corresponding pathological findings. In addition, the increased or decreased values remained within the range of the historical control values. In fact, histopathological assessment revealed only sporadic and/or spontaneous lesions. In conclusion, the no-observed-adverse-effect-level (NOAEL) for l-Ser was, therefore, determined to be at least a dietary dose of 5.0% (2765.0 mg/kg body weight/day for males and 2905.1 mg/kg body weight/day for females) under the present experimental conditions.     

The Farmland and Rural Improvement Project budget under the Agriculture Basic Law in Japan

The Farmland and Rural Improvement Project (FRIP) system met socioeconomic needs during the time the Agriculture Basic Law (ABL) was in effect. Four hundred and forty publications and revisions of project execution guidelines between fiscal years (FY) 1960 and 1995 addressed the need to modify the FRIP systems. From the viewpoint of budgets, the budget share of the Farmland Improvement Project (FIP) in annual national public works budgets decreased in close correlation with percentages of gross agricultural product in gross domestic product (GDP). The Rural Improvement Project (RIP) share, however, increased during the same time period, in close correlation with percentages of non-farmers living in rural villages. Consequently, there was little change in the FRIP budget share. These changes in FRIP budget structure brought a certain level of FIP investment per hectare, with no increase since FY 1980. In addition, the RIP investment played a role in narrowing the gap in the living infrastructure investment per capita between urban and rural areas.     

Evaluation of a PCR-restriction fragment length polymorphism (PCR-RFLP) assay for molecular epidemiological study of Shiga toxin-producing Escherichia coli

In this study, we have evaluated our recently developed polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay for the molecular subtyping of Shiga toxin-producing Escherichia coli (STEC). A total of 200 STEC strains including O157 (n=100), O26 (n=50), O111 (n=10), and non-O26/O111/O157 (n=40) serogroups isolated during 2005-2006 in Japan, which were identified to be clonally different by pulsed-field gel electrophoresis (PFGE) were further analyzed by the PCR-RFLP assay in comparison to PFGE. Ninety-five of O157, 48 of O26, five of O111 and 19 of non-O26/O111/O157 STEC strains yielded one to three amplicons ranging from 6.0 to 15.5 kb in size by the specific primer set targeting region V which is located in the upstream of stx genes. These strains were classified into 41 (O157), 8 (O26), 4 (O111) and 17 (non-O26/O111/O157) groups based on the RFLP patterns obtained by subsequent restriction digestion, respectively. Although the discriminatory power of PCR-RFLP assay was somewhat less than that of PFGE, it is more convenient for molecular subtyping of STEC strains especially for O157, the most important serogroup implicated in human diseases, as well as to identify the outbreak-associated isolates because of its simplicity, rapidity, ease and good reproducibility.