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131.
Koji Azegami Takanori Tsukamoto Takayuki Matsuura Tatsuji Ohara Yasuhiro Inoue Akifumi Mizuno Kouji Yoshida Hideo Bessho Shigeru Kimura Masao Goto 《Journal of General Plant Pathology》2004,70(6):336-341
Invasion and colonization of mature apple fruit by a transformant of Erwinia amylovora tagged with bioluminescence genes from Vibrio fischeri was examined. The transformant was deposited on cut surfaces of fruit stems, wounds on the shoulders and calyces, injured fruit-bearing twigs of harvested apple fruit, and cut fruit flesh. After incubation in closed stainless steel or plastic boxes at 25°C, fruit were periodically observed with a two-dimensional luminometer. The presence of the transformant in luminous areas was confirmed by isolating it on selective media. E. amylovora, when deposited in fruit stems: (1) can invade mature as well as immature apple fruit; (2) vertically and horizontally spreads and colonizes along vascular bundles, increasing its population; (3) reaches the calyx end and the flesh just under the exocarp within 3–4 days after inoculation; (4) when deposited on cut fruit flesh, irrespective of its maturity, can easily increase its population and survive 2–4 weeks or more at 25°C; and (5) even at the time of fruit maturation, can migrate within twigs rapidly and reaches the abscission layers between fruit-bearing twigs and fruit stems. 相似文献
132.
Graft unions of nursery stock of grapevine (Vitis vinifera L.) collected in Japan yielded pathogenic and nonpathogenic strains of Agrobacterium. On the basis of classical diagnostic tests, a sequence analysis, and a multiplex polymerase chain reaction method previously
reported, the pathogenic strain was identified as Agrobacterium tumefaciens biovar 3, whereas the nonpathogenic strains were assigned to Agrobacterium radiobacter biovar 3. Stems of tomato (Lycopersicon esculentum Mill.) seedlings were inoculated with both A. tumefaciens biovar 3 strain G-Ag-27 as a pathogen and one of the control strains isolated from grapevine or A. radiobacter biovar 2 strain K84 as competitors to assay the suppression of gall formation caused by the pathogen. In a test with a 1 : 1
pathogen/nonpathogen cell ratio, all A. radiobacter biovar 3 strains reduced gall incidence and size compared to that of the positive control inoculated only with the pathogen.
Strain VAR03-1 was especially effective in reducing the incidence of gall formation on grapevine and reduced gall size by
84%–100% of those on the positive control. Many tested nonpathogenic biovar 3 strains were bacteriocinogenic, causing an inhibition
zone against A. tumefaciens biovar 3 strains on YMA medium. Strain VAR03-1 was the most effective against indicator strains and appears to be a promising
agent for controlling crown gall of grapevine. 相似文献
133.
134.
Tomato (Lycopersicon esculentum Mill., cv. Momotaro) plants were grown in nutrient solutions with several levels of urea, nitrate, and ammonium alone or in combination to evaluate the role of urea as an organic nitrogen source compared with that of nitrate and/or ammonium as inorganic nitrogen sources. Nitrogen deficiency and excess symptoms were detected in the urea-fed plants at lower (28 mg N L-1) and higher nitrogen levels (336, 504 mg N L-1), respectively. The effect of urea on plant growth and leaf elemental composition was intermediate between that of nitrate and ammonium. Solution pH under urea nutrition slightly increased or remained stable. When plants were cultured with the solution containing 168 mg N L-1, the total dry weight of the plants which received urea+nitrate was significantly higher than that of the plant which received urea and was almost equal to that of the plants which received nitrate or nitrate+ammonium. Both absorption and utilization of nitrogen in the plants fed with urea decreased compared with those of the plants fed with nitrate or ammonium. The insufficient absorption and utilization of nitrogen were estimated to be the main factors associated with the growth reduction of tomato plants under urea nutrition. However, combined application of urea and nitrate is useful for adequate plant growth without a reduction of the cation absorption in tomato while maintaining a stable solution pH. 相似文献
135.
Ozawa Hideo Yamamura Akira Kimijima Takeo Ishizaki Shoichiro Ochiai Yoshihiro 《Fisheries Science》2020,86(1):197-202
Fisheries Science - Tropomyosin (TM) is the major allergen found in invertebrates, including shrimp. To reduce the allergenicity of shrimp muscle, attempts were made to eliminate TM from the muscle... 相似文献
136.
Koichi Yoneyama Xiaonan Xie Kaori Yoneyama Takahito Nomura Ikuo Takahashi Tadao Asami Narumi Mori Kohki Akiyama Miyuki Kusajima Hideo Nakashita 《Pest management science》2019,75(9):2353-2359
Strigolactones (SLs) are carotenoid‐derived plant secondary metabolites that play important roles in various aspects of plant growth and development as plant hormones, and in rhizosphere communications with symbiotic microbes and also root parasitic weeds. Therefore, sophisticated regulation of the biosynthesis, perception and functions of SLs is expected to promote symbiosis of beneficial microbes including arbuscular mycorrhizal (AM) fungi and also to retard parasitism by devastating root parasitic weeds. We have developed SL mimics with different skeletons, SL biosynthesis inhibitors acting at different biosynthetic steps, SL perception inhibitors that covalently bind to the SL receptor D14, and SL function inhibitors that bind to the serine residue at the catalytic site. In greenhouse pot tests, TIS108, an azole‐type SL biosynthesis inhibitor effectively reduced numbers of attached root parasites Orobanche minor and Striga hermonthica without affecting their host plants; tomato and rice, respectively. AM colonization resulted in weak but distinctly enhanced plant resistance to pathogens. SL mimics can be used to promote AM symbiosis and to reduce the application rate of systemic‐acquired resistance inducers which are generally phytotoxic to horticultural crops. © 2019 Society of Chemical Industry 相似文献
137.
Larvae of jack mackerel Trachurus japonicus were sampled in seven depth layers (0–10 m, 10–20 m, 20–30 m, 30–40 m, 40–50 m, 50–70 m, and 70–100 m), with a closing-type
frame net, on 26th–27th February, 2003, at Sta. V (27°50′N, 126°00′E) continental shelf edge in the southern part of East
China Sea, to examine their vertical distribution. Most of the larvae (>90%) occurred in the upper 50 m layer during both
day and night. In the daytime, larvae of length from 3.0 mm to 4.5 mm were most abundant in the 10–20 m layer, those from
5.0 to 6.0 mm were most abundant in the 20–30 m layer, those from 6.0 to 8.0 mm occurred at greater depth, in the 30–40 m
layer, and those more than 9.0 mm were found in the 0–10 m layer and performed ontogenetic vertical migrations. Larvae from
6 mm to 8 mm length performed diurnal vertical migration, for the percentage (16.7%) of larval number in the 0–20 m layer
in the daytime increased to 42.1% at night and the percentage (78.1%) in the 20–50 m layer in the daytime decreased to 49.0%
at night. 相似文献
138.
The exposure of freesia corms to ethylene (C2H4) at ca. 10 μl/l air for only 5 h was sufficient to promote sprouting, either under a closed system in which corms were treated in a sealed space of 3–10 1 or under a flow system in which corms were exposed to a continuous flow of air containing C2H4. Under the closed system, little change in corm response to C2H4 was found with increasing duration of exposure from 5 to 48 h, and the C02 concentration reached nearly 4% after 48 h. On the other hand, under the flow system, in which CO2 did not accumulate above 0.1%, the promotive effect of C2H4 was diminished by extended exposure from 5 to 48 h.Repeated treatment with C2H4 for 23 h daily on 4 successive days resulted in the lowering of the promotive effect as compared with a single treatment, but repeated application of C2H4 for 5 h daily showed the same effect as a single application and gave a high sprouting rate similar to smoke treatment, independent of ambient temperature ranging from 25 to 35° C.Corms exposed to C2H4 for 5 h daily, or to smoke for 4 days, exhibited a better chilling response and advanced flowering. 相似文献
139.
140.
Nobuya Hishiyama Hideki Kayanuma Tohru Matsui Hideo Yano Tsunenori Suganuma Masayuki Funaba Hiroshi Fujise 《Canadian journal of veterinary research》2006,70(4):305-307
Most mammals, including dogs, synthesize vitamin C in the liver. We measured the plasma concentration of vitamin C to assess the body vitamin C status in 15 dogs with a portosystemic shunt (PSS). The plasma biochemical parameters indicated liver abnormalities in all the dogs. In contrast, the plasma concentration of vitamin C ranged from 2.21 to 9.03 mg/L in the 15 dogs and was below the reference range (3.2 to 8.9 mg/L) in only 2 dogs. These findings suggest that vitamin C status is not impaired in dogs with PSS. 相似文献