Degradation of an acylated starch-plastic mulch film in soil and impact on soil microflora

Degradation of an acylated starch-plastic mulch film was evaluated in two soil types, a gray lowland soil (A) and a volcanic andosol (V). Weight loss, tensile strength (TS) loss and loss of percentage elongation (%E) were measured under laboratory conditions (black and white mulch films), and in the field (black films). Changes in the counts of total bacteria, total fungi, gram-negative bacteria, total Fusarium, ATP (adenosine triphosphate) content, % nitrification, pH (H₂O), and total C and total N contents were determined at 4,8, 12, and 20 months in the field test soils where the mulch was repeatedly applied, and compared with controls. Film weight loss was greater in soil V than in soil A in both the laboratory and the field, and the losses were greater in the laboratory than in the field in both soils A and V. Significant TS losses and considerable %E losses were observed. Values were similar in the laboratory and in the field. No significant changes in the counts of bacteria, fungi, gram-negative bacteria, and Fusarium were observed. The ATP content of the test soils increased slightly compared with the initial values. The ATP content in the control soils initially fell, and then increased in response to weeding. Nitrification remained almost unchanged in the test soils, but fell in the control soils until the last sampling. However, the mulch film underwent a definite process of degradation in the soils, with great loss of physical properties and lesser weight loss. This degradation had no adverse impact on the soil microflora.     

Site-level model–data synthesis of terrestrial carbon fluxes in the CarboEastAsia eddy-covariance observation network: toward future modeling efforts

Based on the model–data comparison at the eddy-covariance observation sites from CarboEastAsia datasets, we report the current status of the terrestrial carbon cycle modeling in monsoon Asia. In order to assess the modeling performance and discuss future requirements for both modeling and observation efforts in Asia, we ran eight terrestrial biosphere models at 24 sites from 1901 to 2010. By analyzing the modeled carbon fluxes against the CarboEastAsia datasets, the strengths and weaknesses of terrestrial biosphere modeling over Asia were evaluated. In terms of pattern and magnitude, the carbon fluxes (i.e., gross primary productivity, ecosystem respiration, and net ecosystem exchange) at the temperate and boreal forest sites were simulated best, whereas the simulation results from the tropical forest, cropland, and disturbed sites were poor. The multi-model ensemble mean values showed lower root mean square errors and higher correlations, suggesting that composition of multiple terrestrial biosphere models would be preferable for terrestrial carbon budget assessments in Asia. These results indicate that the current model-based estimation of terrestrial carbon budget has large uncertainties, and future research should further refine the models to permit re-evaluation of the terrestrial carbon budget.     

Cloning of the feline GADD45 cDNA and analysis of its mutation in feline lymphoma cell lines

Growth arrest and DNA damage-inducible protein 45 (GADD45) plays an important role in suppressing multistep carcinogenesis. In this report, we describe the isolation of the complete wild-type feline GADD45 cDNA from feline tissues. Expression of feline GADD45 mRNA was detected in the liver, spleen, kidney, lung, and testis. The predicted amino acid sequences encoded by the full-length feline GADD45 cDNA display sequence homology with those from other vertebrates, and as in the case of human GADD45, cell growth suppression was observed by ectopic expression of feline GADD45. However, no mutations were detected by sequence analysis of feline GADD45 in several feline lymphoma cell lines, indicating that the GADD45 mutation might be uncommon in feline oncogenesis.     

Clinical usefulness of antibodies against Babesia gibsoni detected by ELISA with recombinant P50

The clinical usefulness of antibodies against Babesia gibsoni detected by ELISA with recombinant P50 was examined in dogs in an area where B. gibsoni infection was endemic. Only 8 among 14 dogs with acute type B. gibsoni infection without a previous history of infection were positive. This high percentage of false-negative results is thought to be a weak point of ELISA as a diagnostic tool. However, 14 other anemic dogs with a confirmed history of B. gibsoni infection were all positive, thus confirming the higher sensitivity of ELISA in detecting a history of infection.     

Primary chondrosarcoma in the skull of a dog

Chondrosarcoma of the skull is a rare primary malignant tumor that is slow-growing, but locally aggressive. A 5-year-old, golden retriever was presented to our hospital with a swelling in the left side of her head, and the swelling had slowly enlarged over the previous month. There were no significant changes on the neurological examination. A computed tomography scan revealed a large mass involving bone destruction and prominent matrix mineralization. T1-weighted magnetic resonance imaging showed a slightly low-signal intensity area and a T2-weighted image revealed marked, high-signal intensity. There was compression of the adjacent brain parenchyma. Histopathological examination confirmed the lesion to be a chondrosarcoma.     

<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-dimethylsphingosine,an inhibitor of sphingosine kinase,induces phytoalexin production and hypersensitive cell death of Solanaceae plants without generation of reactive oxygen species

Plant recognition of elicitors derived from pathogens induces various resistant reactions, including production of reactive oxygen species, hypersensitive cell death and accumulation of phytoalexins. Previously, we isolated a ceramide elicitor from Phytophthora infestans, which activates O₂ ⁻ production of potato suspension-cultured cells. In this study, we employed nine ceramide-related chemicals to test their elicitor activity. Although, none of the tested chemicals induced O₂ ⁻ production, N,N-dimethylsphingosine (DMS) induced accumulation of phytoalexin in potato tubers. In potato, tobacco and Nicotiana benthamiana, DMS also induced rapid cell death. DMS-treated potato cells stained with 4′,6-diamidino-2-phenylindole (DAPI) showed chromatin condensation, and isolated DNA from DMS-treated cells had ladder pattern, confirming that DMS-induced plant cell death is a hypersensitive reaction-like programmed cell death. Involvement of ceramide signaling in induction of plant defense reactions is discussed. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Characterisation of QoI‐resistant field isolates of Botrytis cinerea from citrus and strawberry

BACKGROUND: In 2004, field isolates of Botrytis cinerea Pers. ex Fr., resistant to strobilurin fungicides (QoIs), were first found in commercial citrus orchards in Wakayama Prefecture, Japan. Subsequently, QoI‐resistant isolates of this fungus were also detected in plastic strawberry greenhouses in Saga, Ibaraki and Chiba prefectures, Japan. Biological and molecular characterisation of resistant isolates was conducted in this study. RESULTS: QoI‐resistant isolates of B. cinerea grew well on PDA plates containing kresoxim‐methyl or azoxystrobin at 1 mg L^?1, supplemented with 1 mM of n‐propyl gallate, an inhibitor of alternative oxidase, whereas the growth of sensitive isolates was strongly suppressed. Results from this in vitro test were in good agreement with those of fungus inoculation tests in vivo. In resistant isolates, the mutation at amino acid position 143 of the cytochrome b gene, known to be the cause of high QoI resistance in various fungal pathogens, was found, but only occasionally. The heteroplasmy of cytochrome b gene was confirmed, and the wild‐type sequence often present in the majority of resistant isolates, indicating that the proportion of mutated cytochrome b gene was very low. CONCLUSION: The conventional RFLP and sequence analyses of PCR‐amplified cytochrome b gene are insufficient for molecular identification of QoI resistance in B. cinerea. Copyright © 2009 Society of Chemical Industry     

Detection of rickettsial DNA in ixodid ticks recovered from dogs and cats in Japan

DNA from ticks recovered from 1137 dogs and 133 cats from all over Japan were examined for Rickettsia infection by citrate synthase gene (gltA)-based PCR and partial nucleotide sequencing. A total of 91 dog tick samples and 18 cat tick samples showed a single band of the appropriate size in the nested PCR. Sequence analysis was successfully performed on 102 samples. DNA of Rickettsia japonica or closely related Rickettsia spp. strains were detected from 38 ticks in 16 prefectures mainly in western Japan. The other 33, detected from 13 prefectures including Hokkaido and Okinawa, were found to be Rickettsia helvetica or closely related strains. A total of 29 DNA that showed highest homology with Rickettsia akari or closely related strains were detected in 19 prefectures, widespread throughout Japan. Rickettsia canada-like DNA was detected from Haemaphysalis sp. removed from a dog in Fukuoka, and ;Candidatus Rickettsia tarasevichiae'-like DNA was from Ixodes sp. removed from a dog in Hokkaido.