Evaluation of immobilizing agents as soil quality conditioners in addition to their metal(loid) immobilizing effect

In trace metal (TM)-contaminated agricultural soils, management of TM availability is important for safe crop production. In addition, maintenance or improvement of soil quality is vital for sustainable crop cultivation. Decreased TM phytoavailability and increased soil quality can be achieved by the application of various immobilizing agents to soil, which can supply both macronutrients and organic matter. This study investigated the long-term influences of four common immobilizing agents on so...     

Analysis of methanogenic archaeal communities of rumen fluid and rumen particles from Korean black goats

Molecular diversity of methanogens in the rumen of Korean black goats was investigated with 16S rRNA gene clone libraries using methanogen‐specific primers. The libraries were composed of rumen fluid‐associated methanogens (FAM) and rumen particle‐associated methanogens (PAM) from rumen‐fistulated Korean black goats. Among the 141 clones of the FAM library, the sequences were mostly related to two phyla, the Methanobacteriaceae family (77.3%) and the Thermoplasmatales family (22.7%); and among the 68 clones of the PAM library, sequences were also mainly clustered in the two phyla, the Thermoplasmatales family (63.24%) and the Methanobacteriaceae family (35.29%). Most of the sequenced clones in the two libraries were closely related to uncultured methanogenic archaeon. Quantitative real‐time PCR revealed that PAM (8.97 log 10) had significantly higher (P < 0.01) density of methanogens by the methanogenic 16S rRNA gene copies than FAM (7.57 log 10). The two clone libraries also showed difference in Shannon index (FAM library 1.70 and PAM library 1.59) and Chao 1 estimator (FAM library 18 and PAM library 17 operational taxonomic units). Apparent differences found in the microbial community from the two 16S rRNA gene libraries could be a result of such factors as the chemical and physical nature of the target material surface, types or component of diets, the interaction between the methanogens and other microbes, and age of the experimental goats.     

Effects of warming, wetting and nitrogen addition on substrate-induced respiration and temperature sensitivity of heterotrophic respiration in a temperate forest soil

Soil heterotrophic respiration and its temperature sensitivity are affected by various climatic and environmental factors.However,little is known about the combined effects of concurrent climatic and environmental changes,such as climatic warming,changing precipitation regimes,and increasing nitrogen(N)deposition.Therefore,in this study,we investigated the individual and combined effects of warming,wetting,and N addition on soil heterotrophic respiration and temperature sensitivity.We incubated soils collected from a temperate forest in South Korea for 60 d at two temperature levels(15 and 20℃,representing the annual mean temperature of the study site and 5℃warming,respectively),three moisture levels(10%,28%,and 50%water-filled pore space(WFPS),representing dry,moist,and wet conditions,respectively),and two N levels(without N and with N addition equivalent to 50 kg N ha^-1year^-1).On day 30,soils were distributed across five different temperatures(10,15,20,25,and 30℃)for 24 h to determine short-term changes in temperature sensitivity(Q₁₀,change in respiration with 10℃increase in temperature)of soil heterotrophic respiration.After completing the incubation on day 60,we measured substrate-induced respiration(SIR)by adding six labile substrates to the three types of treatments.Wetting treatment(increase from 28%to 50%WFPS)reduced SIR by 40.8%(3.77 to 2.23μg CO₂-C g^-1h^-1),but warming(increase from 15 to 20℃)and N addition increased SIR by 47.7%(3.77 to 5.57μg CO₂-C g^-1h^-1)and 42.0%(3.77 to 5.35μg CO₂-C g^-1h^-1),respectively.A combination of any two treatments did not affect SIR,but the combination of three treatments reduced SIR by 42.4%(3.70 to 2.20μg CO₂-C g^-1h^-1).Wetting treatment increased Q₁₀by 25.0%(2.4 to 3.0).However,warming and N addition reduced Q₁₀by 37.5%(2.4 to 1.5)and 16.7%(2.4 to 2.0),respectively.Warming coupled with wetting did not significantly change Q₁₀,while warming coupled with N addition reduced Q₁₀by 33.3%(2.4 to 1.6).The combination of three treatments increased Q₁₀by 12.5%(2.4 to 2.7).Our results demonstrated that among the three factors,soil moisture is the most important one controlling SIR and Q₁₀.The results suggest that the effect of warming on SIR and Q₁₀can be modified significantly by rainfall variability and elevated N availability.Therefore,this study emphasizes that concurrent climatic and environmental changes,such as increasing rainfall variability and N deposition,should be considered when predicting changes induced by warming in soil respiration and its temperature sensitivity.     

Discrimination and abundance estimation of wild and released abalone Haliotis diversicolor using stable carbon and oxygen isotope analysis in north-eastern Taiwan

The discrimination between wild and released Taiwan abalone Haliotis diversicolor was performed by stable carbon isotope analysis. Abalone samples were collected from Mao Aw Gulf in north-eastern Taiwan. Live abalone and dead shells were collected by divers with an 80 × 80 cm frame. The densities and amounts of wild and released abalone, as well as the survival rates of released abalone, in 1997 and 1998 were estimated. The age of the specimens was also determined from the specific temperature of each month and the inverse relationship between oxygen isotope values and temperatures. Results show that examining stable isotopic profiles proves to be a practical and feasible method for stock discrimination as well as density and abundance estimation. These data would be helpful in assessing the success of abalone culture and release programs, which aim to enhance this valuable marine resource.     

Giant Cell Dermatosis in FeLV-positive Cats

Abstract— Giant cell dermatosisis is reported in six cats with evidence of concurrent feline leukemia virus (FeLV) infection. Scaling, crusting and alopecia, accompanied by pruritus, affected the head and/or face predominantly in most cats; generalized skin disease developed in one cat. Histologically, giant keratinocytes resembling syncytial cells were found in the epidermis and superficial hair follicles, and were accompanied by dyskeratosis, pustules and ulcers. Immunohistochemical staining revealed FeLV antigen in the giant cells and adjacent keratinocytes. FeLV infection may have led to neoplastic alteration of the keratinocytes through recombination with host oncogenes
Resumen  Este artículo se basa en seis gatos con dermatosis de las células gigantes infectados con el virus FeLV. Éstos animales presentaban escamas y costras, así como pérdida de pelo y picor en las regiones de la cabera y cara, predominantemente. Tan solo uno de los gatos desarrolló una dermatosis generalizada. En el exámen histológico se demostró la presencia de keratinocitos gigantes con semejonza a las células sinticiales localizados en la epidermis y folículos pilosos superficiales, acompañados de disqueratosis, pústulas y ülceras. Las finturas histo-inmunológicas demostraron el antígeno FeLV en las células gigantes y keratinocitos adyacentes. La injeccion con el virus FeLV pudo haber conducido a la alteración neoplástica de los keratinocitos a través de la recombinación con los oncogenes del hospedador.     

梨树黑星病的发病及防治研究

 梨树黑星病是我国北方梨树最主要的病害。分布于我国东北、华北、西北与华东各梨产区;在东北地区自辽宁省至黑龙江省都有发生,但重点发生地区則有辽宁省的綏中、兴城、錦西、北鎮、义县和吉林省的延边自治区等。     

Characteristics of glyphosate inhibition of growth in soybean and tobacco callus cultures

Callus cultures or tobacco (Nicotiana tabacum L. cv. While Gold and N. glauca-langsdorffii, a tumour-forming amphidiploid hybrid) and soybean Glycine max L., cv. Chippewa) were used lo study the effect of glyphosate [N-(phosphonnmethyl) glycine) un growth and interactions with growth hormones. Glyphosate inhibited growth both in the dark and light but showed a greater toxicity in the dark. This was contrary to its effect on chlorophyll degradation which was accelerated by light. The inhibition of growth was not reversed by simultaneous addition of aromatic amino acids to the medium. Thus the results suggest a multiple glyphosate action. The tobacco callus tissue was more sensitive to glyphosate than the soybean callus tissue, confirming a difference in tolerance between plant species. Despite the inhibitory effect of glyphosate. the treated tissue revived after being transferred to a glyphosate-free medium. The glyphosate-induced growth inhibition in soybean and tumour-forming tobacco callus cultures also was reversible by high levels of indole-3-acetic acid (IAA), which itself was inhibitory Theglyphosate-IAA interaction in the tissues which were sensitive to IAA suggests that the inhibition of growth by glyphosate was related to auxin levels in these tissues.