排序方式: 共有13条查询结果,搜索用时 31 毫秒
1.
Field studies were undertaken to explore the weed management strategies for transplanted and direct wet-seeded rice in the Dera Ismail Khan district of North-west Frontier Province, Pakistan. The experimental design was a randomized complete block with a split plot arrangement. The main plots consisted of two planting techniques (transplantation and direct seeding), while weed control practises assigned to the subplots included the use of the granular herbicide Sunstar 15WG (ethoxy sulfuron), Machete 60EC (butachlor), conventional hand weeding, and the weedy check (untreated control). Data were recorded on weed dynamics and the agronomic parameters of the rice crop. Economic analyses on the data were also run. The weed density and biomass were lower in the transplantation plots than the direct-seeding plots. The herbicides ethoxy sulfuron and butachlor reduced the density over the weedy check, with a density comparable to hand weeding in 2002, but slightly higher in 2003. As a result of weed management by hand weeding and herbicides, the paddy yield and its components were significantly higher for the transplanted method compared to the direct-seeded method. The comparable yield of herbicides with hand weeding offers an option for the use of herbicides as an alternative management tool. In light of our findings, it is concluded that for good economic returns, rice crops may be transplanted rather than direct-seeded. The herbicides ethoxy sulfuron and butachlor offer a weed control cover comparable with hand weeding under the transplantation method, while butachlor is good for controlling weeds even under the direct-seeded conditions in the agroclimatic conditions of the area. 相似文献
2.
Seed germination and respiratory metabolism under aerobic and anaerobic conditions were studied in the flooding-tolerant and flooding-susceptible varieties of Echinochloa crus-galli with an identical genome and common ancestry . In the flooding-tolerant E. crus-galli var. formosensis , the seeds imbibed under nitrogen could germinate and exhibited an I/N quotient > 0.6. They accelerated glycolysis and concomitantly produced large and equimolar quantities of carbon dioxide and ethanol, suggesting that the seeds of this variety showed operation of the Pasteur effect and respired through alcohol fermentation under anaerobic conditions. The seeds excreted most of the toxic fermentation product. In contrast, the seeds of the flooding-susceptible E. crus-galli var. praticola were capable of germinating only under aerobic conditions through the conventional aerobic respiration and were unable to anaerobically respire to germinate through alcohol fermentation regardless of the presence of both sufficient alcohol dehydrogenase activity and a high redox charge of the pyridine nucleotides. 相似文献
3.
Nobukazu SAISHU Kazutaka MORIMOTO Hiroshi YAMASATO Hiroichi OZAKI Toshiyuki MURASE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1037-1042
Thirty-eight Aerococcus viridans isolates were obtained from milk from
478 cows with clinical mastitis in a farm during the periods between November 2011 and
February 2012, and between December 2012 and March 2013. Additional isolates were obtained
from processed manure (a mixture of composted manure, straw and hydrated lime) and bedding
materials. The processed manure was later used to cover the floor of the stalls in barns
as bedding materials. The temperatures recorded in the composted and processed manure were
not as high as those generally observed during satisfactory composting. To reveal the
association of A. viridans in manure-related products with intramammary
infection in cows, isolates were characterized by their DNA fragment patterns as
determined by pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility
testing. Isolates obtained from milk, processed manure and bedding materials had identical
DNA fragment patterns. Antimicrobial susceptibilities were determined for 29 isolates from
milk, processed manure and bedding materials. Of these, 26 (89.7%) were resistant to
clindamycin, whereas virtually all the isolates were susceptible to 12 other
antimicrobials including cefalosporins that have been used to treat bovine mastitis in
Japan. In vitro, three A. viridans isolates from milk
and an isolate from processed manure survived for 3 hr in Good’s buffer (pH 9) at high
temperature (50°C). The results suggest that the processed manure and bedding materials in
this farm were possible sources of A. viridans that caused infection in
the cows with mastitis. 相似文献
4.
Ryota MATSUYAMA Naotoshi KUNINAGA Tomoya MORIMOTO Tetsuya SHIBANO Akiko SUDO Kazunari SUDO Makoto ASANO Masatsugu SUZUKI Tetsuo ASAI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1179-1181
Plesiomonas shigelloides is a causal agent of gastroenteritis, sepsis
and meningitis in humans. We examined the prevalence of P. shigelloides
among great cormorants (Phalacrocorax carbo hanedae) in Japan and the
antimicrobial susceptibility of isolates. P. shigelloides was isolated
from 33 (47.8%) of 69 fecal samples from great cormorants in 2014. All 33 isolates were
subjected to antimicrobial susceptibility testing using broth microdilution methods, which
showed resistance to ampicillin (31 isolates, 93.9%), tetracycline (two isolates, 6.1%)
and trimethoprim (one isolate, 3.0%). The high prevalence of P.
shigelloides in the great cormorants implicates the possible microbiological
risk to public health. 相似文献
5.
Shu HASHIMOTO Nao SUZUKI Ami AMO Takayuki YAMOCHI Yoshihiko HOSOI Yoshiharu MORIMOTO 《The Journal of reproduction and development》2013,59(5):496-499
Effects of supporting materials during vitrification procedure on the morphologies
of preantral follicles of pig ovaries were assessed. Ovarian cortical sections of
prepubertal pigs were randomly allocated to 5 groups. The sections were vitrified
ultrarapidly with 5 different vitrification devices. The sections were put on 4 fine
needles (Cryosupport), on a thin copper plate, or on a carbon graphite sheet or were
sandwiched between copper plates or between carbon graphite sheets before cooling.
The cooling and warming rates with the graphite sheets were significantly higher than
those with the copper plates (P<0.05). A total of 3,064 follicles were analyzed
following HE staining after vitrification with 5 different devices. The morphologies
follicles vitrified on the Cryosupport or on the graphite sheet were well preserved
compared with those vitrified on the copper plate or between copper plates
(P<0.01). The morphologies of follicles vitrified between copper plates were
mostly damaged (P<0.05). Taken together, good thermally conducting material
supports follicle morphologies of ovaries cryopreserved with ultrarapid
vitrification. 相似文献
6.
Kanae NIIMI Motoko MORIMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):573
To eliminate pathogens, the initiation of an appropriate immune response is critical. When the gastrointestinal nematode, Heligmosomoides polygyrus (Hp), invades the small intestine, a type-2 cytokine response is initiated; however, this response is not sufficient to clear the infection, and chronic infection can ensue. In this study, the host defense against Hp was investigated in mice with a focus on the role of CD4+ T cells. To this end, tissues from the small intestine and mesenteric lymph node (MLN) were collected every day from just after infection until Day 5 because many previous studies have described the later stages of infection from Day 8 to Day 12, during which Hp returns to the lumen and Th2 cytokine expression reaches its peak. In this study, we focused on investigating the initiation of the type-2 immune response. Our results indicated that the larvae encysted by Day 3. Increased type-2 cytokine gene expression started in the small intestine before Day 2 and increased again on Day 5. Interferon (IFN) γ increased significantly on the second day. Flow cytometry and gene expression analysis of MLN cells revealed that CD4+ T cells were not activated until Day 4. These results suggested that innate immune cells in submucosa are activated immediately after infection, but CD4+ T cells accumulate in the cyst zone later. In addition, IFNγ may have an important role in converting type-2 cytokine-producing cells from innate cells to CD4+ T cells. 相似文献
7.
Tatsuya NAKANO Mizuki KONO Kazuki SEGAWA Satoshi KUROSAKA Yoshiharu NAKAOKA Yoshiharu MORIMOTO Tasuku MITANI 《The Journal of reproduction and development》2021,67(2):123
Methylglyoxal (MG) is a precursor for the generation of endogenous advanced glycation end-products involved in various diseases, including infertility. The present study evaluated the motility and developmental competence after in vitro fertilization of mouse sperm which were exposed to MG in the capacitation medium for 1.5 h. Sperm motility was analyzed using an SQA-V automated sperm quality analyzer. Intracellular reactive oxygen species (ROS), membrane integrity, mitochondrial membrane potential, and DNA damage were assessed using flow cytometry. The matured oocytes were inseminated with MG-exposed sperm, and subsequently, the fertilization and embryonic development in vitro were evaluated in vitro. The exposure of sperm to MG did not considerably affect the swim-up of sperm but resulted in a deteriorated sperm motility in a concentration-dependent manner, which was associated with a decreased mitochondrial activity. However, these effects was not accompanied by obvious ROS accumulation or DNA damage. Furthermore, MG diminished the fertilization rate and developmental competence, even after normal fertilization. Collectively, a short-term exposure to MG during sperm capacitation had a critical impact on sperm motility and subsequent embryonic development after fertilization. Considering that sperm would remain in vivo for up to 3 days until fertilization, our findings suggest that sperm can be affected by MG in the female reproductive organs, which may be associated with infertility. 相似文献
8.
9.
Hidehiko OGAWA Ryuichi TAKYU Hiromu MORIMOTO Shuntaro TOEI Hiroshi SAKON Shiori GOTO Shota MORIYA Tomohiro KONO 《The Journal of reproduction and development》2016,62(1):51-58
We previously established trophoblast stem cells from mouse androgenetic embryos (AGTS cells). In this
study, to further characterize AGTS cells, we compared cell proliferation activity between trophoblast stem
(TS) cells and AGTS cells under fibroblast growth factor 4 (FGF4) signaling. TS cells continued to proliferate
and maintained mitotic cell division in the presence of FGF4. After FGF4 deprivation, the cell proliferation
stopped, the rate of M-phase cells decreased, and trophoblast giant cells formed. In contrast, some of AGTS
cells continued to proliferate, and the rate of M-phase cells did not decrease after FGF4 deprivation,
although the other cells differentiated into giant cells. RO3306, an ATP competitor that selectively inhibits
CDK1, inhibited the cell proliferation of both TS and AGTS cells. Under RO3306 treatment, cell death was
induced in AGTS cells but not in TS cells. These results indicate that RO3306 caused TS cells to shift mitotic
cell division to endoreduplication but that some of AGTS cells did not shift to endoreduplication and induced
cell death. In conclusion, the paternal genome facilitated the proliferation of trophoblast cells without FGF4
signaling. 相似文献
10.
Recruitment strategy of swimming crab, Portunus trituberculatus, in Hiuchi-Nada, Japan 总被引:2,自引:0,他引:2
The recruitment strategy of swimming crabs, Portunus trituberculatus, was investigated by field observations and numerical experiments in Hiuchi-Nada, Japan. Calculated dispersal patterns of zoeal and megalopal stages in a three-dimensional numerical model reproduce observed patterns accurately. The temporal change of vertical migration patterns between the 1st and 2nd zoeas and the 3rd and 4th zoeas plays an important role in the process of recruitment of P. trituberculatus from spawning ground to nursery ground. 相似文献