Modeling the effects of N application on growth,yield and plant properties associated with the occurrence of chalky grains of rice

The objective of this study was to propose a model for explaining rice responses to a wide range of N application rates in various growth attributes associated with the occurrence of chalky grains. We improved the sub-model for N uptake process of a previous rice model which was originally developed for explaining genotypic and environmental variations in the whole growth processes, considering the difference in the rate of N loss from the plant-soil system between indigenously supplied soil mineral N and fertilizer N. A total of 80 growth datasets of cultivar ‘Koshihikari’ grown at Shiga prefecture, Japan, in 2010 was utilized for the calibration and validation of the model. The rice growth model well explained the above-ground biomass growth (RMSD = 78.7 g m^?2) and rough dry grain yield (RMSD = 83.2 g m^?2) for the validation data-set, simultaneously. The simulated carbohydrate content available per single spikelet was negatively correlated with the observed percentage of the milky-white grain which includes white-cored grain (r = ?.77, p < .001) for all the data-sets of calibration and validation. On the other hand, the observed percentage of the sum of white-back and white-base grains was closely correlated with the simulated plant N content available per single spikelet (r = ?.59, p < .001). It was suggested that the present rice growth model would rationally explain the effects of N application on the occurrence of the chalky grains through the dynamic change of the carbohydrate content and plant N content available per single spikelet.     

Flavonol Caffeoylglycosides as alpha-Glucosidase Inhibitors from Spiraea cantoniensis Flower

In the screening experiments for rat intestinal alpha-glucosidase inhibitors in 218 plants cultivated in the Japanese temperate region, potent maltase-inhibiting activity was found in the extract of flowers of Spiraea cantoniensis. The enzyme assay guided fractionation of the extract led to the isolation of three flavonol caffeoylglycosides, quercetin 3- O-(6- O-caffeoyl)-beta-galactoside ( 1), kaempferol 3- O-(6- O-caffeoyl)-beta-galactoside ( 2), and kaempferol 3- O-(6- O-caffeoyl)-beta-glucoside ( 3), as rat intestinal maltase inhibitors. This is the first report on the alpha-glucosidase-inhibitory activity of those flavonol caffeoylglycosides. Comparison in the activity of the isolates indicated the importance of caffeoyl substructures in the molecule for the alpha-glucosidase-inhibiting activity. The relatively high contents of the active isolates in the plant suggest that S. cantoniensis could be physiologically useful for treatment of diabetes.     

Naringenin and hesperetin induce growth arrest, apoptosis, and cytoplasmic fat deposit in human preadipocytes

Citrus flavonoids are reported to be promising bioactive compounds against hyperlipidemia and lipid biosynthesis. However, the mechanism of the lipid lowering effect by flavonoids remains unknown. The present study examines the effect of some flavanones on the adipocytic conversion of the human preadipocyte cell line, AML-I. Among four structure-related flavanones including naringenin, naringenin-7-rhamnoglucoside (naringin), hesperetin, and hesperetin-7-rhamnoglucoside (hesperidin), the aglycones such as naringenin and hesperetin exhibited the growth arrest of AML-I cells. When the cells were examined by Annexin V-FITC staining method, it was noticed that growth arrest was induced by apoptotic cell death. In the study of apoptosis-related protein in the naringenin-treated cells, anti-apoptotic proteins such as p-Akt, NF-kappaB, and Bcl-2 were decreased, and pro-apoptotic protein Bad was accumulated by Western blot analysis. Interestingly, exposure of AML-I cells to naringenin or hesperetin during short-term cultures increased cytoplasmic lipid droplets by Sudan Black B staining. Furthermore, expression of fatty acid synthase (FAS) and peroxisome proliferator activated receptor (PPAR)-gamma was enhanced in naringenin-treated cells. These data suggest that apoptosis by flavanones does not inhibit the adipocytic conversion of AML-I preadipocytes. The result also indicates that adipocyte may not be a direct target for the lipid-lowering activity of the flavanones.     

Farm-scale variations in soil color as influenced by organic matter and iron oxides in Japanese paddy fields

To understand how soil color is influenced by soil components at the farm scale, we evaluated spatial variation in soil color and related soil properties in Japanese paddy fields. After harvest of rice, 246 surface soil samples were collected in 10-m grids from five contiguous irrigated paddy fields, each with an area of about 0.5 ha. The samples were analyzed to determine color parameters (L*, a*, and b*), and contents of total C, total N, Fe oxides, sand, and loss-on-ignition. The results obtained were modeled and mapped geostatistically. All color parameters indicated strong spatial dependence with long ranges (>85 m). In contrast, total C and N showed short ranges (about 40 m). The contents of Fe oxides, sand, and loss-on-ignition showed intermediate ranges (50–85 m). The ranges of these properties and their distribution patterns suggested that the contents of total C and N were influenced by long-term application of manure and that sand content was influenced by topography and past land consolidation. Further soil color analysis after removal of organic matter or silt plus clay particles revealed that soil organic matter, texture, and Fe oxides affected soil color parameters in a complex manner. Prediction of total C from soil darkness was hindered by the presence of silt plus clay particles containing Fe oxides. On the other hand, citrate-dithionite extractable Fe was estimated accurately from the b* value (yellowness), which can be useful for predicting the occurrence of akiochi (autumn decline) disease of rice at the farm scale.     

Prevalence of autoantibody in cerebrospinal fluids from dogs with various CNS diseases

To examine the prevalence of autoantibody in canine cerebrospinal fluids (CSFs), CSFs were collected from 14 healthy controls and 88 clinical cases with various diseases in the central nervous system (CNS), and were analyzed by an indirect fluorescence antibody test on frozen sections of the cerebrum from normal Beagle dogs. An anti-astrocyte autoantibody was detected in 31 clinical cases with titers ranging from 1:1 to >/=1:100. All tested cases with necrotizing meningoencephalitis (NME: n=22) and granulomatous meningoencephalitis (GME: n=3) possessed the anti-astrocyte autoantibody, while the autoantibody was negative in most cases with other inflammatory CNS diseases. The autoantibody was also detected in 4 of 12 cases with brain tumors. Hence, examination of the autoantibody in the canine CFS would be significant for diagnosing NME and/or GME, as well as for understanding peritumoral events in cases with brain tumors.     

Differentiation between bovine and ovine strains of Histophilus somni based on the sequences of 16S rDNA and rpoB gene

Nucleotide sequences of 16S rDNA and rpoB gene of 25 bovine and 6 ovine Histophilus somni strains were determined to detect subtle differences between the host animal species. The 1465 nucleotide residues of the 16S rDNA exhibited levels of sequence similarities of 99.4% or more. The high sequence similarity of the 16S rDNA of recently described species H. somni was confirmed in the 31 strains from cattle and sheep. These results suggested that the intra-specific diversity of 16S rDNA was limited in bovine and ovine strains of H. somni. The specific association of strains was also observed in the 311 bp region of rpoB gene which sequence similarities were 98.6% or more. However, the phylogenetic tree analysis of the rpoB gene showed that the ovine strains appeared to form a subgroup recovered in 70% of the bootstrap trees. In the 311 bp region of the ovine strains, a HincII restriction endonuclease site was detected. The PCR-amplified rpoB DNA of 46 bovine and 20 ovine H. somni strains were examined for the digestion with HincII. As the results, 17 strains of ovine strains were cleaved by the enzyme but none of the bovine strains appeared to possess the restriction site. The restriction enzyme analysis of rpoB gene may be useful to differentiate ovine strains from bovine strains of H. somni.     

Interploid crossing overcomes plastome-nuclear genome incompatibility in intersubgeneric hybridization between evergreen and deciduous azaleas

Appearance of albino seedlings caused by plastome-nuclear genome incompatibility was avoided by using polyploid parents in intersubgeneric hybridization between evergreen azaleas and deciduous Rhododendron japonicum f. flavum. Intra- and interploid crosses of 2x or 4x evergreen azaleas with 2xR. japonicum f. flavum showed high capsule set, but their reciprocal crosses failed to set capsules. Green and albino hybrids were obtained from 2x evergreen azaleas × 2xR. japonicum f. flavum crosses where ptDNAs of the green and albino plants were derived from R. japonicum f. flavum (paternal parent) and evergreen azaleas (maternal parents), respectively. All the progenies from the crosses of 4x evergreen azaleas × 2xR. japonicum f. flavum were green triploids with evergreen azalea-specific ptDNA. The efficiency of obtaining green hybrids in interploid crosses was higher than that in intraploid crosses. These results suggest that interploid crosses of 4x evergreen azaleas × 2xR. japonicum f. flavum can overcome plastome-nuclear genome incompatibility between evergreen azalea-specific plastome and the nuclear genome in the resulting hybrid.     

Chicken B lymphoma DT40 cells as a useful tool for in vitro analysis of pathogenic infectious bursal disease virus

Susceptibility of DT40 cells to pathogenic field strains of infectious bursal disease virus (IBDV) including very virulent and classical virulent strains were studied. After the first and second passage of the virus in DT40 cells, IBDV-specific antigen was readily detected in DT40 cells inoculated with the pathogenic field strain infected bursal homogenates. Nucleotide sequence analysis in the VP2 hypervariable domain, which is critical for the virulence of IBDV, revealed no common amino acid substitutions among the pathogenic IBDVs in accordance with the propagation in DT40 cells. These results indicate that DT40 cells are a useful tool for rapid isolation of pathogenic field strains and successive in vitro analysis of IBDV.     

Population size estimation of the pond smelt Hypomesus nipponensis in Lake Kasumigaura and Lake Kitaura,Japan

We estimated the population size of the pond smelt Hypomesus nipponensis at the beginning of the fishing season in Lake Kasumigaura and Lake Kitaura, Japan using two DeLury methods and cohort analysis. A growth curve was estimated on the basis of monthly standard length. The relationship between standard length and weight was utilized for calculating the mean weight on the survey day in a particular month. Total monthly catches in Lake Kasumigaura and Lake Kitaura were calculated using partial monthly pond smelt catch obtained from processing plants located near the lakes between July and December. The total monthly catch was calculated from the total monthly catch weight and the monthly mean weight. The number of boats operating each month, compiled by the Kasumigaura-Kitaura Fisheries Office of Ibaraki Prefecture, was also employed. The estimated initial population sizes were compared with the population level index (PLI) estimated from survey data before the start of the fishing season. No significant differences were detected among the initial population sizes estimated by DeLury method, cohort analysis and PLI. The estimates ranged from 7.4 million to 410 million in Lake Kasumigaura, and from 7.7 million to 44 million in Lake Kitaura.