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71.
Stock enhancement programme for black sea bream, Acanthopagrus schlegelii (Bleeker), in Hiroshima Bay, Japan: a review 总被引:1,自引:0,他引:1
This paper reviews the stock enhancement programme for black sea bream ( Acanthopagrus schlegelii ) in Hiroshima Bay. This bay is one of the biggest production areas for black sea bream in Japan, accounting for about 10% of the total catch of the species in this country in 2004. After intensive fishing pressure caused a drastic decline in the catch of the species in this bay in the 1970s, a stock enhancement programme was conducted in its northern part since 1982 to restore the depleted population. The number of black sea bream juveniles released in 1996 surpassed 9 million, representing the third main species stocked in Japan. Almost 1.4 million of these juveniles were released into Hiroshima Bay. The fast acclimatization of hatchery-reared juveniles released into the bay may have contributed to the recovery of landings in the late 1980s and 1990s. However, this recovery was accompanied by a reduction in the market price of black sea bream. Further studies to assess the effectiveness of the stock enhancement programme as well as the carrying capacity of Hiroshima Bay to maintain the stock of black sea bream at a stable, healthy level are desirable. The necessity of evaluating the secondary effects derived from using a reduced number of breeders as well as finding new markets are suggested. 相似文献
72.
Yumiko Yamasaki Hitoshi Kunoh Hiroyuki Yamamoto Kazuya Akimitsu 《Journal of General Plant Pathology》2007,73(3):168-179
Volatile compounds of plants, including monoterpenes, are a possible source of signal molecules that induce defense systems
to protect plants from tissue damage. Volatile compounds from rough lemon leaves were trapped by solid-phase microextraction
fibers in sealed vials, and subsequent gas chromatography–mass spectrometry and gas chromatography analyses identified the
profile of the major components, mainly various monoterpenes. Among several monoterpenes examined, citral, citronellal, and
linalool significantly inhibited the spore germination and hyphal growth of Alternaria alternata. The effect of linalool was fungistatic, while the effects of citral and citronellal were partially fungicidal. Wounding
of rough lemon leaves induced a significant increase in release of monoterpenes. The release of linalool was the most abundant
and was 14.5 times that of unwounded rough lemon leaves. Unlike the wounding treatment, microbe attack did not significantly
change monoterpene releases, and there was statistically no difference found in the peak areas from microbe-treated and untreated
leaves. Linalool, limonene, and β-pinene also had insect-repellant effects on wild-type Drosophila melanogaster. Expression patterns of defense-related genes in rough lemon and rice significantly changed after treatment with vapors of
monoterpene volatiles. Taking these results together, monoterpene volatiles are likely to play roles in the defense of rough
lemon against microbe and insect pathogens. 相似文献
73.
Fujinami N Hosoi Y Kato H Matsumoto K Saeki K Iritani A 《The Journal of reproduction and development》2004,50(2):171-178
Developmental potential of bovine embryos that are not artificially activated after intracytoplasmic sperm injection (ICSI) is generally very low. In this study, we investigated effects of artificial activation with ethanol on kinetics of maturation promoting factor (MPF) activity (p34(cdc2) kinase activity) and development of bovine oocytes following ICSI. Treatment of oocytes with ethanol at 4 h after ICSI improved their first cleavage and further preimplantation development (51% vs. 13%, 14% vs. 4%: treatment with vs. without ethanol, respectively). MPF activity of oocytes was lowered until at least 2 h after ICSI. In oocytes without activation after ICSI, MPF activity temporarily elevated at 6 h after ICSI, whereas this phenomena was not observed in the oocytes treated with ethanol. Furthermore, MPF activity was elevated 20 h after ICSI in oocytes activated with ethanol, whereas this elevation of MPF activity was not shown in oocytes without activation. These results indicate that the stimulus of sperm was sufficient to lower MPF activity of oocytes following ICSI, and moreover the activation treatment of bovine oocytes with ethanol after ICSI served to maintain the low levels of MPF activity until the next cell cycle started. 相似文献
74.
The effect of alkali extraction on the lignin monomeric composition was examined inEucalyptus camaldulensis andE. globulus by thioacidolysis using extractive-free samples as a control. Results showed that the effect onEucalyptus is different among species and among sample positions in the trunk, although a small amount of lignin is solubilized during the extraction in all samples. In addition, it was proved that lignin extracted by the alkali extraction is not always guaiacyl-rich, probably relating to the original lignin monomeric composition, which depends on the sample species or the sample position in the trunk. 相似文献
75.
In 1998, rhus (Rhus javanica L.) yellows (RhY), caused by phytoplasma, was found in Miyagi Prefecture, Japan. In vector transmission tests, Hishimonus sellatus acquired RhY phytoplasma from diseased R. javanica and transmitted it to healthy R. javanica. Twenty-two species of herbaceous plants in 10 families were infected with RhY phytoplasma by H. sellatus. The host range and main symptoms on test plants of RhY phytoplasma differed from those of Macrosteles striifrons-transmitted phytoplasmas, which belong to the same 16Sr I group phytoplasma.
Received 6 December 1999/ Accepted in revised form 14 May 2000 相似文献
76.
Yoshinori MATSUDA Hideyoshi TOYODA Yasunari KATO Koji KAKUTANI Takayuki NAKANISHI Miki BINGO Teruo NONOMURA Seiji OUCHI 《Journal of General Plant Pathology》2000,66(1):59-63
A nonpathogenic mutant of Ralstonia solanacearum was produced by the insertion of transposon Tn4431. The mutagenized gene was then cloned from a genomic DNA library by the
gene tagging method, using the labeled lux operon located on Tn4431 of pUCD623 as a hybridization probe. From nucleotide sequence analysis of the transposon-inserted
genomic clone, the hrpB gene was shown to be disrupted by the inserted transposon. Tomato plants were inoculated with the hrpB-disrupted mutant bacteria, for which multiplication and translocation were then monitored using the colony hybridization
method. In addition, the original pathogenic bacteria in which the lux operon had been functionally ligated with the genomic promoter were also used for inoculation and traced by their bioluminescence.
Multiplication of the hrpB-disrupted mutant was suppressed initially in the invaded root tissues and then in upper hypocotyl after translocation, suggesting
that the pathogenic strain of R. solanacearum overcomes at least two steps of host responses expressed in root and hypocotyl tissues. Thus, our approach for molecular
monitoring of the bacteria enabled us to precisely analyze the infection behavior of the pathogenic bacteria in planta.
Received 16 April 1999/ Accepted in revised form 10 August 1999 相似文献
77.
78.
79.
Hitomi MATSUNARI Toshihiro KOBAYASHI Masahito WATANABE Kazuhiro UMEYAMA Kazuaki NAKANO Takahiro KANAI Taisuke MATSUDA Masaki NAGAYA Manami HARA Hiromitsu NAKAUCHI Hiroshi NAGASHIMA 《The Journal of reproduction and development》2014,60(3):230-237
The development and regeneration of the pancreas is of considerable interest because of the role of these processes in
pancreatic diseases, such as diabetes. Here, we sought to develop a large animal model in which the pancreatic cell lineage
could be tracked. The pancreatic and duodenal homeobox-1 (Pdx1) gene promoter was conjugated to Venus, a
green fluorescent protein, and introduced into 370 in vitro-matured porcine oocytes by intracytoplasmic
sperm injection-mediated gene transfer. These oocytes were transferred into four recipient gilts, all of which became
pregnant. Three gilts were sacrificed at 47–65 days of gestation, and the fourth was allowed to farrow. Seven of 16 fetuses
obtained were transgenic (Tg) and exhibited pancreas-specific green fluorescence. The fourth recipient gilt produced a litter
of six piglets, two of which were Tg. The founder Tg offspring matured normally and produced healthy first-generation (G1)
progeny. A postweaning autopsy of four 27-day-old G1 Tg piglets confirmed the pancreas-specific Venus expression.
Immunostaining of the pancreatic tissue indicated the transgene was expressed in β-cells. Pancreatic islets from Tg pigs were
transplanted under the renal capsules of NOD/SCID mice and expressed fluorescence up to one month after transplantation. Tg
G1 pigs developed normally and had blood glucose levels within the normal range. Insulin levels before and after sexual
maturity were within normal ranges, as were other blood biochemistry parameters, indicating that pancreatic function was
normal. We conclude that Pdx1-Venus Tg pigs represent a large animal model suitable for research on
pancreatic development/regeneration and diabetes. 相似文献