Multiplex PCR for the identification of Agrobacterium biovar 3 strains

A biovar 3-specific primer set Ab3-F3/Ab3-R4 was designed based on the comparison of sequences of the 16S rDNA region of agrobacteria and related rhizobia for rapid identification of Agrobacterium biovar 3 strains. A 570-bp 16S rDNA fragment was amplified from cell lysates of Agrobacterium biovar 3 strains by polymerase chain reaction (PCR) using Ab3-F3/Ab3-R4 primers. Discrimination of Agrobacterium tumefaciens biovar 3 from Agrobacterium radiobacter biovar 3 and of Agrobacterium biovar 3 strains from other Agrobacterium strains was done simultaneously using multiplex PCR with a mixture of two primer sets (Ab3-F3/Ab3-R4 and VCF3/VCR3) previously designed for the virC region of Ti-plasmid and Ri-plasmid.     

Detection of tumorigenic Agrobacterium strains from infected apple saplings by colony PCR with improved PCR primers

With the colony polymerase chain reaction (PCR), the specificity of newly prepared primer sets VCF2/VCR2, VCF3/VCR3, VCF4/VCR4, and VCF5/VCR5 to Ti or Ri plasmids in Agrobacterium strains were compared to that of the conventional set VCF/VCR. At first, control strains, which consisted of a nonpathogenic strain and phytopathogenic strains carrying Ti or Ri plasmid, were used. VCF3/VCR3 and VCF5/VCR5 were highly specific to all the phytopathogenic strains, whereas the others were not. These two primer sets were superior to VCF/VCR in their specificity with colony PCR to tumorigenic Agrobacterium strains isolated from apple saplings.     

Effects of dietary energy intake and cold exposure on kinetics of plasma glucose metabolism in sheep

An isotope dilution method using [U-(13)C]glucose injection was applied to determine the effects of dietary energy intake and cold exposure on plasma glucose metabolism in sheep. The sheep were assigned to two dietary treatments and were fed on diets containing either 100% or 160% of ME and both containing 150% of dietary crude protein intake for maintenance. The sheep were exposed from a thermoneutral environment (23 degrees C) to a cold environment (2-4 degrees C) for 5 days. The isotope dilution method was performed on the 18th day in the thermoneutral environment and on the fifth day of cold exposure. Plasma concentrations of glucose and NEFA increased (p < 0.05) during cold exposure for both diets. Plasma glucose pool size remained unchanged (p = 0.67), but plasma glucose turnover rate tended to increase (p = 0.07) with increased energy intake. Both pool size and turnover rate of plasma glucose increased (p = 0.01 and p = 0.0001, respectively) during cold exposure. No significant diet x environment interaction was detected. It is concluded that plasma glucose metabolism was influenced by both dietary energy intake and cold exposure, and plasma glucose metabolism in response to cold exposure was not modified by energy intake in sheep under the conditions (2-4 degrees C on the fifth day) of the present experiment.     

Potential nitrogen immobilization as influenced by available carbon in Japanese arable and forest soils

Abstract

Iron oxide is the most important electron acceptor in paddy fields. We aimed to suppress the methane emission from paddy fields over the long term by single application of iron materials. A revolving furnace slag (RFS; 245 g Fe kg^-1) and a spent disposable portable body warmer (PBW; 550 g Fe kg_-1) were used as iron materials. Samples of a soil with a low iron level (18.5 g Fe kg^-1), hearafter referred to as “a low-iron soil” and of a soil with a high iron level (28.5 g Fe kg^-1), hearafter referred to as “an iron-rich soil,” were put into 3 L pots. At the beginning of the experiment, RFS was applied to the pots at the rate of 20 and 40 t ha^-1, while PBW was applied at the rate of 10 t ha^-1 only, and in the control both were not applied. Methane and nitrous oxide emissions from the potted soils with rice plants were measured by the closed chamber method in 2001 and 2002. When RFS was applied at the rates of 20 and 40 t ha^-1 to the low-iron soil, the total methane emission during the cultivation period significantly decreased by 25–50% without a loss of grain yield. Applied iron materials clearly acted as electron acceptors, based on the increase in the amount of ferrous iron in soil. However, the suppressive effect was not evident in the iron-rich soil treated with RFS or PBW. On the other hand, nitrous oxide emission increased by 30–95%. As a whole, when the total methane and nitrous oxide emissions in the low-iron soil were converted to total greenhouse gas emissions expressed as CO₂- C equivalents in line with the global warming potential, the total greenhouse gas emissions decreased by about 50% due to the application of RFS.     

RFLP mapping of the three major genes, Vrn1, Q and B1, on the long arm of chromosome 5A of wheat

Chromosome 5A of wheat carries several major genes of agronomic importance, including Vrn1 controlling spring/winter wheat difference, Q determining spike morphology and B1 inhibiting awn development. A population of single-chromosome recombinant lines from the cross between two chromosome substitution lines, 'Chinese Spring' (Cappelle-Desprez 5A) and 'Chinese Spring' (Triticum spelta 5A) was developed to map these genes on the long arm of chromosome 5A relative to RFLP markers. Using 120 recombinant lines, a map of approximately 230 cM in length was constructed. The gene order was centromere– Vrn1– Q– B1. The Vrn1 locus was tightly linked to two RFLP markers, Xbcd450 and Xrz395 with 0.8 cM, and to Xpsr426 with 5.0 cM. The Vrn1-adjacent region was located in the central of the long arm, approximately 90 cM from the centromere. The chromosome region around Q and the 5A/4A translocation break-point were mapped by three RFLP markers, and their order was found to be Q– Xpsr370– Xcdo457–4A/5A break-point– Xpsr164. The B1 locus was located on the most distal portion of the long arm. This revised version was published online in July 2006 with corrections to the Cover Date.     

Nasal nocardiosis in a calf.

Nasal nocardiosis was found in a female Japanese Black calf, 11 months of age. Macroscopically, the posterior half of the left nasal passage was completely obstructed by yellowish brown caseous substance and the mucosa was irregularly thickened. In the brain, a few soft brown foci were present in the olfactory bulb and frontal lobe. Microscopically, there were closely packed granulomas in the nasal cavity and brain. The lesions were characterized by a center of cellular debris surrounded by epithelioid macrophages, neutrophils, lymphocytes and multinucleated giant cells of the Langhans type. Special stains revealed the presence of a large number of filamentous branching gram-positive, partially acid-fast organisms in these epithelioid cells and giant cells, and in cellular debris.     

Hydathode function and changes in contents of elements in eddo exposed to zinc in hydroponic solution

To explore the zinc stress response in eddo, plants were grown for 15 d in hydroponic solutions containing 1 (control), 200, and 1000 μM zinc, and the hydathode function and changes in the contents of various elements in these plants were investigated. Under 1000 μM zinc, the dry weights of leaf blades and roots are decreased by 17 and 42%, respectively. The zinc contents in leaf blades, petioles, corms, and roots increased with increasing zinc levels in the solution. The zinc content in roots was 6.57 mg g^?1 dry weight, which was 2.8–4.3 times higher than in other plant parts under 1000 μM zinc. These results demonstrate that the severe root damage occurring under 1000 μM zinc is due to higher zinc content in the roots. Under zinc stress, the contents of iron and copper in roots increased, but the contents of magnesium and calcium in petioles, corms, and roots, iron in leaf blades and corms, and manganese in petioles and corms decreased. In the guttation fluid, the concentrations of zinc, magnesium, and potassium increased, while the iron concentration decreased under 1000 μM zinc. Thus, elemental changes occurred in the guttation fluid as well as in different plant parts in eddo. In the 200 and 1000 μM zinc treatments, the amount of zinc eliminated via guttation was 2.8 and 8.5 times higher, respectively, than in the control. The results indicate that guttation partly contributes to the excretion of excess zinc under zinc stress conditions.     

Effect of cyclophosphamide and carrageenan on resistance of mice to Erysipelothrix rhusiopathiae

The immunosuppressive effect of cyclophosphamide (CY) or carrageenan (CG) treatment was investigated to clarify the mechanism of resistance of mice to Erysipelothrix rhusiopathiae infection. In mice inoculated with attenuated E. rhusiopathiae, death occurred and bacterial growth in the spleen was enhanced only by CY treatment; in CG-treated mice, no death occurred and bacterial growth in the spleen was kept at a low level for at least 23 days, similar to that of nontreated control mice. These results indicated that polymorphonuclear leucocytes rather than macrophages may play an important role in the resistance of mice to E. rhusiopathiae infection.     

Changes in molecular structure of biodegradable plastics during degradation in soils estimated by FT-IR and NMR

Among the biodegradable plastic specimens (poly-(3-hydroxy-butylate-valerate) (PHB / V), poly-(ε-caprolactone) (PCL), poly-(butylene succinate) (PBS), poly-(butylene succinate and adipate) (PBSA), and poly-lactide (PLA)) that were placed in soils for 1 year at nineteen sites in Japan, plastic specimens with appreciable biodegradation were studied for the transformation of the chemical structure by FT-IR, ¹H-NMR, and ¹³C-NMR. No appreciable differences in the main absorbency-bands of the atomic groups were recognized by FT-IR for any of the plastic specimens tested. However, both ¹H-NMR and ¹³C-NMR analyses suggested that molecular structure of the PHB / V specimens changed after 1 year placement in soils. Based on the assignment of the respective signals of chemical shifts derived from valerate, selective degradation of the valerate moiety in the PHB / V specimens was observed. In contrast, although weight loss, and/or a decrease in tensile strength and elongation were observed after the placement in soils for the PCL, PBS, PBSA, and PLA specimens, the analyses of these specimens by FT-IR, ¹H-NMR, and ¹³C-NMR did not reveal any changes in their molecular structure.