Comparison of the rooting ability of virus infected and virus-free cuttings of sweet potatoes (Ipomoea batatas Poir.) and an anatomical comparison of the roots

Summary

The rooting abilities of the filamentous virus infected and the virus-free cuttings of sweet potato (Ipomoea batatas Poir.) were compared, with an anatomical comparison of the root. The diameters of the pith and the vascular bundle cylinder at the node of the virus-free cutting were larger than in those of virus infected ones. Thicker and more vigorous roots were initiated in the virus-free cutting. The diameter of the central cylinder and the thickness of the cortical layer of the root were larger in the virus-free cutting than in the virus infected one. Larger and more numerous vessels developed, and larger and more distinct meristematic tissues surrounding the protophloem poles also developed in a fan form in the root of the virus-free cutting. The weight of the leaf and stem of the plant 80.d after planting in the field were larger in the virus-free cutting than in the virus infected cutting. From these results, the following assumptions on roots in the virus-free cutting can be made. Thicker roots with larger vessels and thicker meristematic tissues develop in the virus-free cutting because the meristematic activity is high in the tissues in the vicinity of the vascular bundle cylinder at the node, due to the recovery of normal physiological function by removal of the virus. There are fewer roots in the virus-free cutting because the smaller total area of the root is sufficient to absorb the nutrient elements owing to superior development of the vessels and meristematic tissues in the root. In the field, the larger weight of the leaf and stem in the virus-free cutting is caused by the high absorption ability of nutrient elements from the root.     

Early cell enlargement by night-time heating of fruit produce watermelon fruit (Citrullus lanatus Matsum. et Nakai) with high sucrose content

To investigate the effects of night-time temperature on cell and fruit size, and sugar accumulation in watermelon fruit, fruits were treated with high night-time temperatures in a greenhouse. The minimum night-time ambient temperature of the heating box (18 °C) was approximately 6 °C higher than that of the control. The length, diameter and weight of heat-treated fruit at the end of heating treatment, 16 days after anthesis (DAA), were significantly greater than that of control fruit, but those at harvesting, 42 DAA, were almost the same in both treatments. Mean cell size of the outer portion of heat-treated fruit at 16 DAA was significantly larger than that of the control. Cell size of the fruits at 42 DAA did not differ between heat-treated and control fruits. Sucrose, glucose and fructose content of fruit at 16 DAA did not differ between heat-treated and control fruit. However, sucrose content of the outer portion of heat-treated fruit was 162% of that of control fruit at 42 DAA. Glucose and fructose contents at 42 DAA did not differ between heat-treated and control fruit, except glucose content of outer portion.     

Therapeutic potential of canine bone marrow stromal cells (BMSCs) in the carbon tetrachloride (CCl4) induced chronic liver dysfunction mouse model

Regenerative medicine using bone marrow cells is an attractive therapy for the cure of patients with severe liver disease. Here, we show the therapeutic potential of canine bone marrow stromal cells (BMSCs) in mouse models of CCl(4)-induced chronic liver dysfunction. We used two different models for xenotransplantation, nude mice and cyclosporine A (CSA) immunosuppressed mice. Serum parameters from a standard liver panel were not improved following transplantation. However, fibrotic liver lesions with severe inflammation were decreased in CCl(4)-treated CSA mice following BMSC transplantation. Effective migration of transplanted canine BMSCs was limited to persistently injured liver in CCl(4)-treated CSA mice, where they may be effective in resolving inflammatory fibrotic lesions. These results suggest that canine BMSCs are an effective cell source for liver regeneration.     

Molecular characterization of a β-conglycinin deficient soybean

Summary The soybean seed storage protein β-conglycinin has a low amino acid score, shows lower functional gelling properties compared with glycinin and contains a major allergen. The wild soybean (Glycine soja Sieb et Zucc.) QT2 lacks all the subunits of β-conglycinin, and this deficiency is controlled by a single dominant gene Scg-1 (suppressor of β-conglycinin). Scg-1 was introduced into a soybean cultivar Fukuyutaka from QT2 and this near-isogenic line was designated as QY7-25. Segregation analyses of the progeny derived from a cross between QY7-25 and the wild type did not show any significant changes caused by Scg-1 in the germination ratio and seed weight. Low amounts of mRNAs for the α ’, α and β subunits of β-conglycinin were detected by RT-PCR in QY7-25. We revealed that an α subunit mRNA expressed from a region which replaced with mutant line in the near-isogenic line QY7-25 by single nucleotide polymorphisms analysis. In addition, an abnormal splicing event in a cDNA clone for the β subunit isolated from immature seed of QY7-25 was observed. Southern analysis using the coding region of α ’ subunit gene as a probe revealed a polymorphism between QY7-25 and wild type and this genotypes co-segregate with the deficiency of β-conglycinin subunits. These results suggest that the β-conglycinin deficiency might be controlled by a claster region of β-conglycinin subunit genes. In the present study, no agronomical disadvantage in QY7-25 was observed, confirming that Scg-1 is a valuable gene for soybean breeding.     

Antimicrobial resistance in fecal Escherichia coli isolated from growing chickens on commercial broiler farms

To investigate the effects of rearing practices of commercial broiler chickens on the incidence of antimicrobial resistance in commensal Escherichia coli isolates, fecal E. coli isolates obtained in 4 farms were screened for anitimicrobial resistance. Ten E. coli isolates were recovered from each of the fecal samples collected from 10 birds in the farms at the ages of 2 days, 14-17 days, and 47-50 days. In 2 out of the 4 farms, no antimicrobials were used during the rearing period. In the other two farms, following collection of the fecal samples at 14 and 15 days of age, oxytetracycline (OTC), sulfadimethoxine (SDMX), and tylosin were given to birds on one farm and SDMX was used in the other. Isolates resistant to ampicillin and OTC that were obtained from an untreated flock at different sampling times were closely related to each other by pulsed-field gel electrophoresis patterns (PFGE) of XbaI-digested chromosomal DNA. PFGE analysis together with in vitro conjugation experiments suggested that diversity of resistance phenotypes within a clone may be resulted from the acquisition and loss of R-plasmids in an untreated and a treated flock. The numbers of resistance phenotypes observed among fecal isolates increased during the growth of the chickens in all the farms. The results in the present study suggest that persistence of commensal E. coli strains resistant to antimicrobials even in the absence of antimicrobial administration. It is also hypothesized that horizontal transmission of resistance determinants resulted in the emergence of different resistance phenotypes in those farms.     

Genotypic change of porcine circovirus type 2 on Japanese pig farms as revealed by restriction fragment length polymorphism analysis

Porcine circovirus type 2 (PCV2) has been recognized as the causal agent of postweaning multisystemic wasting syndrome and can be divided into two major genotypic groups. We developed a method of restriction fragment length polymorphism (RFLP) analysis of PCV2 open reading frame 2 for easy discrimination between the two major groups. Genotyping of PCV2 isolates from 10 Japanese commercial pig farms was performed, and the analysis revealed that both PCV2 groups and at least five RFLP types of PCV2 are prevalent in Japan. On two farms, the genotypes of the PCV2 isolates in the spring of 2007 were different from those in the autumn of 2006. One genotype may have become dominant within only six months on these farms.     

Identification of quantitative trait loci associated with boiled seed hardness in soybean

Boiled seed hardness is an important factor in the processing of soybean food products such as nimame and natto. Little information is available on the genetic basis for boiled seed hardness, despite the wide variation in this trait. DNA markers linked to the gene controlling this trait should be useful in soybean breeding programs because of the difficulty of its evaluation. In this report, quantitative trait locus (QTL) analysis was performed to reveal the genetic factors associated with boiled seed hardness using a recombinant inbred line population developed from a cross between two Japanese cultivars, ‘Natto-shoryu’ and ‘Hyoukei-kuro 3’, which differ largely in boiled seed hardness, which in ‘Natto-shoryu’ is about twice that of ‘Hyoukei-kuro 3’. Two significantly stable QTLs, qHbs3-1 and qHbs6-1, were identified on chromosomes 3 and 6, for which the ‘Hyoukei-kuro 3’ alleles contribute to decrease boiled seed hardness for both QTLs. qHbs3-1 also showed significant effects in progeny of a residual heterozygous line and in a different segregating population. Given its substantial effect on boiled seed hardness, SSR markers closely linked to qHbs3-1, such as BARCSOYSSR_03_0165 and BARCSOYSSR_03_0185, could be useful for marker-assisted selection in soybean breeding.     

Sorption and desorption studies of Cs and Sr in contaminated soil samples around Fukushima Daiichi Nuclear Power Plant

Journal of Soils and Sediments - Huge amounts of radiocesium, radiostrontium, and fission products were released into the atmosphere during the Fukushima Daiichi Nuclear Power Plant (FDNPP)...