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1.
Burkholderia plantarii , the pathogen of bacterial seedling blight of rice, was detected in paddy water. Its concentration rose in July and August.
The bacterial concentration in the paddy water was always higher along levees than at distances more than 5 m from levees.
Confirmed to be released into water when graminaceous weeds were immersed, B. plantarii survived for at least 4 days at 30°C. B. plantarii was splashed at least 30 cm upward by rain splash in the field. Harvested seeds, which had been sprayed with B. plantarii released from graminaceous weeds at the flowering stage, retained the bacteria. Bacterial seedling blight occurred when the
seeds were then sown in nursery boxes. These results indicated that graminaceous weeds growing on levees of paddy fields are
a source of infection of the disease and that rice seeds are infected through the paddy water.
Received 23 May 2002/ Accepted in revised form 1 September 2002 相似文献
2.
Chie SUZUKI Yosuke SAKAGUCHI Hiroyoshi HOSHI Koji YOSHIOKA 《The Journal of reproduction and development》2016,62(1):79-86
The effects of lipid-rich bovine serum albumin (LR-BSA) on the development of porcine blastocysts produced
in vitro were examined. Addition of 0.5 to 5 mg/ml LR-BSA to porcine blastocyst medium
(PBM) from Day 5 (Day 0 = in vitro fertilization) significantly increased the hatching rates
of blastocysts on Day 7 and the total cell numbers in Day-7 blastocysts. When Day-5 blastocysts were cultured
with PBM alone, PBM containing LR-BSA, recombinant human serum albumin or fatty acid-free BSA, addition of
LR-BSA significantly enhanced hatching rates and the cell number in blastocysts that survived compared with
other treatments. The diameter, ATP content and numbers of both inner cell mass and total cells in Day-6 and
Day-7 blastocysts cultured with PBM containing LR-BSA were significantly higher than in blastocysts cultured
with PBM alone, whereas LR-BSA had no effect on mitochondrial membrane potential. The mRNA levels of enzymes
involved in fatty acid metabolism and β-oxidation (ACSL1, ACSL3,
CPT1, CPT2 and KAT) in Day-7 blastocysts were
significantly upregulated by the addition of LR-BSA. The results indicated that LR-BSA enhanced hatching
ability and quality of porcine blastocysts produced in vitro, as determined by ATP content,
blastocyst diameter and expression levels of the specific genes, suggesting that the stimulatory effects of
LR-BSA arise from lipids bound to albumin. 相似文献
3.
Tamura K Arai H Ueno E Saito C Yagihara H Isotani M Ono K Washizu T Bonkobara M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(9):925-930
Dendritic cell (DC) vaccination is one of the most attractive immunotherapies for malignancies in dogs. To examine the differences in DC-mediated immune responses from different types of malignancies in dogs, we vaccinated dogs using autologous DCs pulsed with keyhole limpet hemocyanin (KLH) and cell lysate prepared from squamous cell carcinoma SCC2/88 (SCC-KLH-DC), histiocytic sarcoma CHS-5 (CHS-KLH-DC), or B cell leukemia GL-1 (GL-KLH-DC) in vitro. In vivo inductions of immune responses against these tumor cells were compared by the delayed-type hypersensitivity (DTH) skin test. The DTH response against SCC2/88 cells were observed in dogs vaccinated with autologous SCC-KLH-DC, while the response was undetectable against CHS-5 and GL-1 cells in dogs vaccinated with autologous CHS-KLH-DC and GL-KLH-DC. Skin biopsies taken from DTH challenge sites were then examined for immunohistochemistry, and recruitment of CD8 and CD4 T cells was detected at the site where SCC2/88 cells were inoculated in dogs vaccinated with SCC-KLH-DC. By contrast, neither CD8 nor CD4 T cell infiltration was found at the DTH challenge site in the dogs vaccinated with CHS-KLH-DC or GL-KLH-DC. These findings may reflect that the efficacy of immune induction by DC vaccination varies among tumor types and that immune responses could be inducible in squamous cell carcinoma. Our results encouraged further investigation of therapeutic vaccination for dogs with advanced squamous cell carcinoma in clinical trials. 相似文献
4.
A cytokinin-like effect of chiral 2-α-methylbenzylamino-4-alkylamino-6-chloro-1,3,5-triazines was found using a rhizome-inducing assay with Cyperus serotinus Rottb. tubers. C. serotinus tubers germinated in distilled water yielded plantlets with roots and leaves. Secondary rhizomes were normally not observed within the regular 14-day incubation time in water culture, whereas after increasing incubation periods a very short rhizome appeared (controls). 6-Benzylaminopurine (BA) significantly stimulated rhizome induction, while other plant hormones were inactive. The (R)-isomers of the 1, 3, 5-triazine compounds also stimulated induction of the rhizomes, whereas the (S)-isomers did not. The described rhizome induction system seems to be suitable as a cytokinin bioassay. The (R)-1, 3, 5-triazine compounds showing rhizome-inducing activity (RI activity) inhibited root formation and plant growth at high concentrations with symptoms which were very similar to those of BA. Therefore, the (R)-isomers appear to act as cytokinins in the rhizome induction assay. 相似文献
5.
This review evaluates the quality of bovine embryos developed from in vitro-matured (IVM) and -fertilized (IVF) oocytes cultured in either serum-free or serum-containing media. Bovine embryos cultured in serum-supplemented medium contain numerous cytoplasmic lipid droplets and immature mitochondria compared to those cultured in serum-free medium. The accumulation of cytoplasmic lipids in embryos developed in serum-containing medium may be a result of incorporation of lipoproteins from the serum and may result in impaired function of mitochondria. The improved serum-free media (IVMD101 and IVD101) offer several advantages over culture in serum-containing medium, including increased rates of blastocyst formation and higher cell numbers. Additionally, the survival and hatching rates of embryos produced in serum-free media after post-thaw culture were superior to those of embryos produced in the serum-containing medium, suggesting that the abnormal accumulation of cytoplasmic lipids in embryos may have a negative effect on the sensitivity of embryos to chilling and freezing. These serum-free culture systems have proven to be beneficial for the production of good quality embryos from IVM-IVF bovine oocytes. Furthermore, recent studies have shown a correlation between mitochondrial function (oxygen consumption) and embryo quality. A new method using scanning electrochemical microscopy may be capable of assessing the viability and developmental potential of bovine embryos. 相似文献
6.
Real‐time polymerase chain reaction (PCR) assays for 11 representative rumen bacterial species were validated. The sensitivity was tested by using the serially diluted target 16S rDNA from respective bacterial species. The recovery of the target DNA and the assay reproducibility were determined using DNA from rumen fluid spiked with different quantities of the target. Minimum detection levels for the target were 10–100 copies in pure culture. The recovery of the added target ranged from 82.4 to 116.6%. The intra‐ and inter‐assay variations of each assay were <9.4 and <12.6%, respectively. Therefore, the real‐time PCR assays evaluated in the present study are considered to be sufficiently reliable for monitoring all 11 bacterial species in the rumen. The assays were then applied to the monitoring of the bacterial species attached to ruminally incubated rice straw. Among the monitored fibrolytic species, Fibrobacter succinogenes was found to be the most dominant, accounting for 2.61% of total bacteria after 24 h incubation. Selenomonas ruminantium and Streptococcus bovis, non‐fibrolytics, were detected on the rice straw at 8.96% and 1.16% of total bacteria, respectively. Such high levels of non‐fibrolytics on the plant fiber suggest a synergistic relationship between fibrolytics and non‐fibrolytics. 相似文献
7.
Takashi Hara Hiroyoshi Iwata Kazutoshi Okuno Katsuhiro Matsui Ryo Ohsawa 《Breeding Science》2011,61(4):394-404
Photoperiod sensitivity is an important trait related to crop adaptation and ecological breeding in common buckwheat (Fagopyrum esculentum Moench). Although photoperiod sensitivity in this species is thought to be controlled by quantitative trait loci (QTLs), no genes or regions related to photoperiod sensitivity had been identified until now. Here, we identified QTLs controlling photoperiod sensitivity by QTL analysis in a segregating F4 population (n = 100) derived from a cross of two autogamous lines, 02AL113(Kyukei SC2)LH.self and C0408-0 RP. The F4 progenies were genotyped with three markers for photoperiod-sensitivity candidate genes, which were identified based on homology to photoperiod-sensitivity genes in Arabidopsis and 76 expressed sequence tag markers. Among the three photoperiod-sensitivity candidate genes (FeCCA1, FeELF3 and FeCOL3) identified in common buckwheat, FeELF3 was associated with photoperiod sensitivity. Two EST regions, Fest_L0606_4 and Fest_L0337_6, were associated with photoperiod sensitivity and explained 20.0% and 14.2% of the phenotypic variation, respectively. For both EST regions, the allele from 02AL113(Kyukei SC2)LH.self led to early flowering. An epistatic interaction was also confirmed between Fest_L0606_4 and Fest_L0337_6. These results demonstrate that photoperiod sensitivity in common buckwheat is controlled by a pathway consisting of photoperiod-sensitivity candidate genes as well as multiple gene action. 相似文献
8.
Togo Tsuji Austin Mambo Lackson K. Phiri Ronald Msoni Sesele B. Sokotela Olusegun A. Yerokun 《Soil Science and Plant Nutrition》2005,51(7):935-942
Total sulphur content of some benchmark soils was evaluated by correlating with the contents of soil organic C and amorphous oxides (Al and Fe), and the particle size distribution. An equation model to calculate the content of total soil sulphur was first obtained by regression analysis. Introducing these chemical and physical data of all the map units except for the wetlands into the equation model, the sulphur level on a national scale was estimated for each soil mapping unit in the exploratory soil map of Zambia. Second, the total sulphur content was rated into 3 classes based on the frequency distribution of the total sulphur content in the benchmark soils. Finally, the rated total sulphur content was incorporated into the national soil map database of GIS to produce a map with the total sulphur content of Zambian soils. The extent of each class was calculated and the distribution of the areas was examined in relation to rainfall and soil formation. 相似文献
9.
10.
Ninomiya H Inomata T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(11):1149-1154
The microvasculature of the eye of 10 pigs was investigated using scanning electron micrographs of corrosion casts. The ciliary body, iris and bulbar conjunctiva were supplied by the iridociliary ring artery via the long posterior ciliary artery. Capillaries of the ciliary process were of large diameter (23.2-27.5 microm) with an irregular bore, forming a thoroughfare channel draining blood in the ciliary arterioles into the pars plana venous vessels. Arterioles and venules in the iris exhibited a zigzag or spiral features. The third palpebra was supplied by the anterior ciliary artery. The capillary bed of the third palpebra was dense and was formed by many rows of fine hair-pin loops. Capillaries in the bulbar conjunctiva formed a sparse network disposing approximately parallel to the epithelium and formed a well-developed venous plexus, draining into the vortex veins. Retinal arterioles formed a slender and long course to capillaries. Retinal capillaries were extremely thin (3.0-4.0 microm in diameter). The choroid was supplied by the short posterior ciliary arteries. Choroidal arterioles exhibited a thick and short course to the choriocapillaris. The choriocapillaris was flat and sinusoid-like (8.9-13.9 microm in diameter), forming a dense sheet-like network. Blood from the choroid emptied into the episcleral vein via the vortex vein. Blood from the retina was drained by the posterior ciliary veins. The functional significance of this vascular architecture was discussed. 相似文献