Simulation model of rainfed rice production on sloping land in northeast Thailand

In northeast Thailand, the rapid expansion of rainfed paddy fields has decreased the stability of rice production. This paper describes a model that computes rice production on the basis of the hydrologic conditions of rainfed paddy fields on hill slopes. The model well expressed the hydrologic processes, rice yield, and production at the study site. We simulated rice production as uphill paddy plots are abandoned, increasing catchment area, under various rainfall conditions. The simulation showed that rice yield and stability increase as uphill plots are abandoned, although the total rice production decreases. Thus, the effect of catchment size on rice production in each plot was quantified. The model proved to be useful for analyzing rainfed rice production under various land and water conditions.     

Biocontrol of Pythium root rot on lisianthus using a new dark septate endophytic fungus Hyaloscypha variabilis J1PC1

European Journal of Plant Pathology - Pythium root rot is one of the most destructive diseases on lisianthus in Japan. Current management strategies against Pythium root rot are insufficient in...     

Lime-nitrogen application affects nitrification, denitrification, and N2O emission in an acidic tea soil

Lime-N (calcium cyanamide, CaCN₂) acts as both fertilizer and pesticide. Lime-N may reduce nitrous oxide (N₂O) emission from soil, although its effectiveness and the relative mechanisms are not well understood. The aim of the study was to quantify the effect of lime-N on N₂O emission from the acidic soil of tea fields. The study design consisted of two treatments: conventional fertilizer (CF) (application of conventional organo-chemical fertilizer) and lime-N (LN) (application of approximately 53 % of the applied N as lime-N and the remaining as conventional organo-chemical fertilizer). Both treatments had the same amount of N, P₂O₅, and K₂O applied to soil between plant canopies; fertilizer was incorporated into soil. We measured N₂O emissions and environmental and microbial parameters of soil between plant canopies and under the canopy of tea plants, including the concentrations of dicyandiamide and cyanamide derived from lime-N. Nitrous oxide emission from soil between plant canopies was lower in the LN treatment than in the CF treatment, and soil ammonium oxidation activity and soil denitrification rate decreased after lime-N application. We applied the acetylene inhibition technique and analyzed isotopomer ratios of N₂O; the results of both techniques suggested that denitrification was the major process of N₂O production in the soil between plant canopies, despite relatively low water-filled pore space. Cumulative N₂O emission over the 366 days of the experiment was 36.0 % lower in the LN treatment than in the CF treatment (P?<?0.05). Our results suggest that lime-N application decreases N₂O emission by inhibiting both nitrification and denitrification processes in the acidic soil.     

Detection of SNPs in fish DNA: application of the fluorogenic ribonuclease protection (FRIP) assay for the authentication of food contents

The fluorogenic ribonuclease protection (FRIP) assay was used to detect single nucleotide polymorphisms (SNPs) in commercially produced fish products. By using fluorescence resonance energy transfer (FRET) between fluorophore and quencher labeled probes, the species-specific cleavage of sample RNA was detected by measuring the fluorescence intensity during the FRIP assay. We were able to discriminate raw and thermally processed eel and tuna species using the FRIP-based SNP detection method. Furthermore, the intensity of fluorescence was correlated with the mutant/wild-type ratio. These results suggest that the FRIP assay is a useful method for the in situ confirmation of labels of fishery foods during food production.     

Collembolan community dynamics during deciduous forests regeneration in Japan

The structure and feeding group composition of collembolan communities were studied in secondary deciduous forests of different ages to investigate the collembolan community response to environmental changes associated with forest cycles. The study was carried out at eight sites forming a chronosequence (1, 4, 12, 24, 51, 54, 71 and 128 years after clear cutting) of deciduous forest stands in northern Ibaraki (Japan). Total collembolan density and species richness was low at the 1-year-old site, and there was little difference in density among sites over 4 years of age. The density of sucking feeders was especially low at the 1-year-old site. Species richness of trees of a diameter at breast height (DBH)<5 cm positively correlated with the density of fungal feeders. Species richness of total Collembolans and of sucking feeders correlated positively with the water content of the organic layer. Ordination of the collembolan community with Canonical Correspondence Analysis suggested that species richness of larger trees (DBH 5 cm) contributed to the differences in species composition of fungal feeders and sucking feeders. We conclude that total abundance and species richness of collembolans recovered within 4 years after clear-cutting, but species composition of fungal feeders and sucking feeders took longer to recover.     

Resistance to <Emphasis Type="Italic">Phytophthora infestans</Emphasis>: exploring genes required for disease resistance in Solanaceae plants

The oomycete Phytophthora infestans is the causal agent of potato late blight, one of the most destructive and historically significant pathogens in agricultural production. A virus-induced gene silencing-based screening of the solanaceous model plant N. benthamiana resulted in revealing a wide range of resistance mechanisms of solanaceous plants against this pathogen. In this article, we present an overview of the various pathways involved in the N. benthamiana–P. infestans pathosystem, including some of the follow-up work that was triggered by these findings. The purpose of this review is to assemble these findings and integrate them into our current understanding of plant pathogen defense mechanisms and discuss their potential application for the development of potato resistance to P. infestans.     

Surgical outcomes in dogs with tracheal collapse treated with a novel cross-and-hook braided endoluminal stent

BackgroundStenting is an effective treatment option for tracheal collapse in dogs. Cross-braided tracheal stents are currently the norm in veterinary medicine, but cross-and-hook braided stents have recently been adopted in human medicine. We examined whether stents manufactured using this novel braiding technique provided additional advantages for the treatment of tracheal collapse in dogs.ObjectivesTo evaluate the outcomes of cross-and-hook braided stent implantation in the treatment of tracheal collapse in dogs.MethodsThe medical records of 22 client-owned dogs that underwent luminal placement of cross-and-hook braided Fauna Stents for the treatment of tracheal collapse between January 2018 and July 2021 were examined and data on canine signalment, clinical signs, diagnostic test results, surgical outcomes, and postoperative complications were retrieved and analyzed statistically.ResultsTwenty-six stents were surgically implanted, with 20 dogs (90.9%) receiving one stent and the remaining two (9.1%) receiving two or more stents. All dogs survived the procedure. The median survival time at a median follow-up of 990 days was 879 days. At the final follow-up examination, loss or mild improvement of cough was observed in all dogs.ConclusionsCompared with conventional lumen stents, the cross-and-hook braided Fauna Stent offered a higher survival rate and improved clinical symptoms in all patients. The results of this study suggest that the Fauna Stent may be a promising treatment option for dogs with tracheal collapse.