Genetic polymorphism and virulence of Colletotrichum gloeosporioides isolated from strawberry (Fragaria × ananassa Duchesne)

To analyze genetic relationships among Colletotrichum gloeosporioides isolates; 34 isolates were collected from strawberries all over Japan, but primarily from Chiba Prefecture, and 20 were isolated from hosts other than strawberry. These isolates were assayed for virulence on strawberries and subjected to a fingerprint (FP) analysis by repetitive extragenic palindromic-PCR. Most of the isolates that were highly virulent to strawberries had relatively similar FPs even though they were isolated from various host plants (strawberry, cyclamen, nipplefruit and Japanese pear) in different regions. A cluster analysis revealed that the highly virulent and the weakly virulent isolates tended to form individual clusters, indicating that the highly virulent strains of C. gloeosporioides, which were genetically close to isolates with similar FPs and distinguishable from the weakly virulent strains, were responsible for strawberry anthracnose in Japan.     

Distribution of protoporphyrin in female broiler chickens affected with protoporphyria

One hundred thirty-seven broiler chickens at a poultry meat processing plant had dark green to black livers. Thirty-one chickens of these were collected at random and examined pathologically and biochemically. All of thirty-one chickens were female. The chickens showed mild retarded growth and a remarkable atrophy of the gallbladders. Microscopically, the livers showed dark brown pigments in the Kupffer cells, hepatocytes, and portal triads. These pigments showed birefringence with a Maltese-cross pattern under polarized light. Hyperplasia of the cholangioles, fibrosis, and infiltration of inflammatory cells were present in the portal triads. All the examined samples showed the same dark brown pigments in alveolar walls of the lungs. A high concentration of protoporphyrin was detected in affected livers, marrow, and feces (489, 104, and 116 microg/g wet wt., respectively) by biochemical assay.     

Induction and sequencing of Rousette bat interferon alpha and beta genes

Bats are considered to be natural reservoirs for several viruses of clinical importance, including rabies virus, Nipah virus, and Hendra virus. Type I interferons (IFNs) is an important part of the immune system in the defense against viral infection. To investigate the function of type I IFNs upon viral infection in bats, the nucleic acid, and amino acid sequences of Egyptian Rousette (Rousettus aegyptiacus) IFN-alpha and -beta were characterized. Sequence data indicated that bat IFN-alpha consists of 562-bp encoded 187-aa, and IFN-beta consisted of 558-bp encoded 186-aa. Phylogenetic analysis of the overall identity of IFN-beta shared the highest sequence homology with pig IFN-beta in both nucleotide and amino acid level. Stimulation of bat primary kidney cells (BPKCs) and bat lung cell lines, Tb-1 Lu, with polyinosinic-polycytidylic acid (poly(I:C)) or exogenous bat type I IFNs resulted in increased type I IFNs mRNA expression in BPKCs, but not in Tb-1 Lu. Characterization of the bat IFN-alpha and -beta genes allows understanding of the immune responses upon stimulation in different tissues, thus providing practical strategies for control and treatment of clinically important diseases. These results are important especially for the virus infection, and suggest that future molecular studies on virus infection experiment of bats in vitro will require careful consideration of the differences of type I IFN expression patterns in different cell types.     

Simple and sensitive BIO-PCR detection of potato blackleg pathogens from stem,tuber, and soil samples

Journal of General Plant Pathology - A BIO-PCR was developed for the detection of potato blackleg pathogens, including Pectobacterium wasabiae (Pw), P. atrosepticum (Pa), P. carotovorum subsp....     

Comparison of the growth traits of a commercial pioneer tree species,paper mulberry (Broussonetia papyrifera L. Vent.), with those of shade-tolerant tree species: investigation of the ecophysiological mechanisms underlying shade-intolerance

In rural areas of northern Laos, a commercially valuable pioneer tree species, paper mulberry (Broussonetia papyrifera L. Vent.) has been recommended for intercropping under plantations of commercial trees. However, less is understood about the growth of this pioneer tree species in the understorey and the mechanism underlying the shade intolerance. We measured growth characteristics for seedlings of paper mulberry under four light intensities. We compared the relative growth rates in aboveground biomass and standing leaf area (RGR_mass and RGR_leaf), light-capture efficiency, and seeding-level mass-based daily photosynthetic rates (A _mass) with those of field-grown seedlings of eight shade-tolerant species to identify factors potentially responsible for shade-intolerance. Most growth traits of the paper mulberry seedlings did not differ consistently from those of the shade tolerant species. The ecophysiological–architectural model software showed higher A _mass and RGR_mass capacity in paper mulberry than in shade-tolerant species. Despite their higher RGR_mass, paper mulberry seedlings had negative RGR_leaf under shaded conditions due to short leaf lifespan. The linear RGR_mass–RGR_leaf relationship for paper mulberry had a high RGR_mass intercept, indicating that a high RGR_mass was required to provide positive RGR_leaf. Progressive decreases in standing leaf area with time, and possibly photosynthesis, appear to be responsible for the shade-intolerance of paper mulberry. Although intercropping of paper mulberry has been suggested in the species’ native region, understorey cultivation of paper mulberry would only be possible with relatively open canopies.     

Composition and Regiodistribution of Fatty Acids in Triacylglycerols and Phospholipids from Red and Black Rices

Regiospecific profiles of fatty acids (FA) of triacylglycerols (TAG) and phospholipids (PL) isolated from red and black rices were investigated. The lipids extracted from red and black rices were separated by thin‐layer chromatography (TLC) into eight subfractions, respectively. With a few exceptions, the major lipid components were TAG (76.4–80.5%), free FA (7.2–9.8%), and phospholipids (3.5–3.6%), while hydrocarbons, steryl esters, diacylglycerols (1,3‐DAG and 1,2‐DAG), and monoacylglycerols were present in minor proportions (0.1–4.1%). The PL components isolated from the two cultivars were phosphatidyl choline (52.3–53.7%), phosphatidyl ethanolamine (22.3–23.1%), phosphatidyl inositol (20.6–21.3%), and others (<3.4%). No significant differences (P < 0.05) in FA distribution were found when these cultivars were compared. The principal characteristics of the FA distribution in the TAG and PL were evident in the rices between the two cultivars: unsaturated FA were predominantly located at the sn‐2 position (77.3–96.8%), while saturated FA primary occupied the sn‐1 or the sn‐3 position (35.0–78.7%) in these lipids. The results of this study could provide useful information to both consumers and producers during manufacture of traditional rice foods in Japan.     

Effects of central administration of glucagon on feed intake and endocrine responses in sheep

This study was conducted to investigate effects of glucagon intracerebroventricularly administered on feed intake and endocrine changes in sheep. Four male sheep (48–55 kg BW) were used. The animals were acclimatized to be fed alfalfa hay cubes at 12.00 hour. Human glucagon (40 and 80 µg/0.5 mL) was injected into the lateral ventricle at 12.00 hour. Blood samples were taken every 10 min from 30 min before to 180 min after the glucagon injection. Soon after the injection, the animals were given alfalfa hay cubes, and the amounts of the feed eaten within 2 h were measured. Feed intakes were significantly (P < 0.05) suppressed by 80 µg of glucagon. Plasma glucose levels in control animals were gradually decreased after the feeding, whilst those in glucagon‐treated animals were temporarily elevated just after the feeding and then kept higher than control levels. Plasma insulin was abruptly elevated after the feeding and was maintained at higher levels than before the feeding in all treatments. Plasma NEFA concentrations were decreased after the feeding in all treatments. A tendency of increase in plasma cortisol levels occurred in glucagon‐injected animals. The present study provides the first evidence that glucagon directly acts on the brain, then inhibiting feeding behavior and inducing endocrine responses in ruminants.     

Evaluation of the Subchronic Toxicity of Dietary Administered Equisetum arvense in F344 Rats

Equisetum arvense, commonly known as the field horsetail, has potential as a new functional food ingredient. However, little information is available on its side effects, and the general toxicity of Equisetum arvense has yet to be examined in detail. In the present study, we evaluated the influence of administration in diet at doses of 0, 0.3, 1 and 3% for 13 weeks in male and female F344 rats. No toxicity was detected with reference to clinical signs, body weight, urinalysis, hematology and serum biochemistry data and organ weights. Microscopic examination revealed no histopathological lesions associated with treatment. In conclusion, the no-observed-adverse-effect level (NOAEL) for Equisetum arvense was determined to be greater than 3% in both sexes of F344 rat (males and females: >1.79 g/kg BW/day and >1.85 g/kg BW/day, respectively) under the conditions of the present study.     

Gross nitrification rates in four Japanese forest soils: heterotrophic versus autotrophic and the regulation factors for the nitrification

Measurements of gross NH ₄ ⁺ and NO ₃ ^? production in forest soils were conducted using the ¹⁵N pool dilution method. Mineral topsoils (0?C10?cm depth) were collected from four forests from northern to southern Japan with a natural climate gradient to elucidate the mechanisms regulating gross nitrification rates in forest soils. Additionally, we attempted to evaluate the relative importance of heterotrophic nitrification in gross total nitrification using acetylene as a specific inhibitor of autotrophic nitrification. Distinct differences were found among sites in the gross rates of NH ₄ ⁺ production (3.1?C11.4?mg?N?kg^?1?day^?1) and gross total nitrification (0.0?C6.1?mg?N?kg^?1?day^?1). The rates of gross heterotrophic nitrification were low in this study, indicating that heterotrophic nitrification is of minor importance in most forest mineral topsoils in Japan. Significant relations were found between gross autotrophic nitrification and gross NH ₄ ⁺ production, soil N, and soil C concentrations, but none was found between gross autotrophic nitrification and soil pH. We determined the critical value of the gross NH ₄ ⁺ production rates for gross autotrophic nitrification under which no gross autotrophic nitrification occurred, as well as the critical soil C/N ratio above which gross autotrophic nitrification ceased. Results show that tight coupling of production and consumption of NH ₄ ⁺ prevents autotrophic nitrifiers from utilizing NH ₄ ⁺ as long as NH ₄ ⁺ availability is low.