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621.
622.
Akifumi Mizuno Takanori Tsukamoto Yoshiaki Shimizu Hitoshi Ooya Takayuki Matsuura Norihiko Saito Shigeyoshi Sato Shigemi Kikuchi Tsuneyasu Uzuki Kouji Azegami 《Journal of General Plant Pathology》2010,76(1):43-51
Black lesions on shoots of European pear trees observed in an orchard in Yamagata Prefecture in May 2007 were suspected to
be caused by a bacterial pathogen. The surface of the colonies isolated on a high sucrose medium did not have the crater morphology
that is characteristic of E. amylovora bvs. 1–3, and a specific DNA fragment was amplified from the isolates in the PCR using the EprpoD primer set. The partial
sequences of the 16S rRNA gene placed the isolates in the genus Erwinia. The isolates differed serologically from E. amylovora biovars and E. pyrifoliae in an Ouchterlony double-diffusion test although their bacterial properties suggested that they are closely related to E. amylovora biovars and E. pyrifoliae. In a DNA–DNA hybridization test, the relatedness between the isolates and E. amylovora biovars or E. pyrifoliae did not exceed 70% level, indicating that they are independent species. Thus, the isolates belongs to the genus Erwnia but are not E. amylovra or E. pyrifoliae. After succulent pear shoots were injected with bacterial suspensions (109, 108, 107 and 106 cfu/ml) of the isolates, lesions formed with 109 and 108 cfu/ml, but the disease incidence with 108 cfu/ml was much lower than with E. amylovora and E. pyrifoliae. Virulence of the present isolates is thus thought to be very weak. On the basis of these results, we consider that this
is a new shoot disease of European pear. In the 2007 season, all affected trees were pulled out after harvest. No symptoms
have been observed in field surveys since the fruitlet season in 2007. 相似文献
623.
Intergeneric hybridization was performed between Brassica rapa and Diplotaxis tenuifolia following embryo rescue. Twenty-three F1 hybrid plants were developed from the cross B. rapa × D. tenuifolia and confirmed to be amphihaploids with 21 chromosomes in mitosis. Chromosome doubling of F1 hybrids by colchicine treatment resulted into five amphidiploid plants which exhibited (20–21)II + (0–2)I at metaphase I (MI) of pollen mother cells. Sib-crossing and/or open-pollination among amphidiploid plants for more than four generations resulted in the development of an ADt-06 line with reproductive systems capable of maintaining an amphidiploid line. The ADt-06 line was intermediate in some morphological traits between two parental species, and was characterized by a slightly pungent taste as a physiological trait. Analyses for genomic DNA confirmed that this line was a hybrid between two species. This new amphidiploid ADt-06 line could be a useful genetic resource for the breeding of new leafy salad vegetables. 相似文献
624.
Identification and molecular mapping of Flowering Date1 (FD1), a major photoperiod insensitivity gene in the adzuki bean (Vigna angularis) 下载免费PDF全文
Hiroki Yamamoto Yuki Horiuchi Reina Ogura Hiroaki Sakai Hitoshi Sato Kiyoaki Kato 《Plant Breeding》2016,135(6):714-720
The induction of flowering under long‐day conditions is an important adaptation by short‐day plants, such as adzuki beans (Vigna angularis), to high‐latitude environments. This study clarified the genetic control underlying the long‐day insensitivity of adzuki bean cultivar ‘Shumari’. ‘Shumari’ was found to be insensitive to a 16‐h day, whereas landrace Acc2265 was highly sensitive. When grown under natural long‐day conditions at Obihiro (42°9′N), Acc2265 initiated flowering at least 80 days after ‘Shumari’. When 86 recombinant inbred lines (RILs) derived from crosses between ‘Shumari’ and Acc2265 were grown under these conditions, their flowering dates ranged from the middle of July to the end of October. The distinct bimodal distribution in the RIL population was due to a single major gene, designated Flowering Date1 (FD1). Molecular mapping showed that FD1 was located between the SSR markers Az02‐37M3 and Az02‐40M9, at distances of 6 and 10.4 cM, respectively, on linkage group 2. RILs carrying FD1S lacked long‐day sensitivity, whereas RILs carrying FD1A were sensitive to long‐day conditions, confirming that FD1 controls long‐day sensitivity. 相似文献
625.
Naoyuki Yamashita Hiroyuki Sase Tsuyoshi Ohizumi Junichi Kurokawa Toshimasa Ohara Yu Morino Masatoshi Kuribayashi Seiichi Ohta Shinji Kaneko Kentaro Hayashi Haruo Fukuhara Tomoyuki Hakamata 《Journal of Forest Research》2016,21(3):115-124
Sensitivity maps of atmospheric acid deposition in Japan have not been updated in 20 years. Here, we propose new relative risk maps of surface water acidification in forests based on a weighted overlay of cumulative potential acid deposition (CPAD) simulated for a 25-year period (1981–2005), including the sensitivities of soil and bedrock to acidification. We assumed that relative acidification risk is high in areas that exhibit high sensitivities of soil and bedrock to acid and have received a large amount of cumulative acid deposition over the past several decades. We aggregated fine soil and bedrock maps into a 20-km mesh for overlay onto an 80-km mesh map of CPAD by considering their spatial structures in Japan. Allocation of the weights among CPAD and soil and bedrock sensitivities was performed based on observational trends in river pH over the past 30 years. The resulting risk map for surface water acidification showed that large areas of western Japan, as well as smaller areas of Hokkaido, Tohoku, Kanto, and Kyushu, are at high risk of surface water acidification. Seventy-seven percent of all rivers for which a declining trend in pH was observed from 2001 to 2009 were also high-risk areas. Acid deposition might be one factor controlling surface water acidification in areas with high bedrock sensitivity, in addition to high CPAD and soil sensitivity, although the risk of soil acidification remains unclear. 相似文献
626.
627.
Coniferous woods were modeled as honeycomb cellular solids consisting of hexagonal-prism tracheids to examine the mechanism for radial compression. Because of the abrupt breaks of radial cell walls, it was assumed that the flrst break followed Euler's equation of buckling. The nominal stress at the buckling of the radial cell wall was theoretically obtained based on this assumption, and the actual nominal stress was obtained experimentally. The theoretical stress was found to correspond almost to the experimental value. This finding suggests that the abrupt first break that occurs in wood under radial compression can be mainly attributed to the buckling of radial cell walls.Part of this work was presented at the 47th annual meeting of the Japan Wood Research Society, Kochi, April 1997 and at the 1997 meeting of the Research Society of Rheology in the Japan Wood Research Society, Tsukuba, December 1997 相似文献
628.
Chemical modification of the herbicide 1-[2-(benzothiazol-2-yl)isopropyl]-4-methyl-3-phenyl-5H-pyrrolin-2-one (MI-2826) has revealed a new oxazinone herbicide, 3-[2-(7-chlorobenzothiazol-2-yl)isopropyl]-2,3-dihydro-6-methyl-5-phenyl-4H-1,3-oxazin-4-one (MI-3069), for use in paddy fields. In comparing the phyototoxicity of the two herbicides to transplanted rice, the latter was superior to the former and kept the same predominant characteristic to control Echinochloa oryzicola Vasin for a long period of time owing to its long-lasting residual effect. 相似文献
629.
Funaba M Uchiyama A Takahashi K Kaneko M Yamamoto H Namikawa K Iriki T Hatano Y Abe M 《American journal of veterinary research》2004,65(2):138-142
OBJECTIVE: To evaluate effects of dietary carbohydrate on urine volume; struvite crystal formation; and calcium, phosphorus, and magnesium balance in clinically normal cats. ANIMALS: 21 healthy adult cats (15 sexually intact males and 6 sexually intact females). PROCEDURE: Diets containing no carbohydrate source (control diet), control plus starch, or control plus fiber were given in a 3 X 3 Latin-square design. The diets were available ad libitum in study 1 (n = 12) and given under restrictions in study 2 (9) to equalize daily intakes of crude protein among the 3 groups. Formation of struvite crystals and balance of calcium, phosphorus, and magnesium were measured. RESULTS: Urine volume was lower in the starch group and fiber group in study 1, whereas no differences were detected among the groups in study 2. Urinary pH and struvite activity product were higher in the starch group in both studies, and the fiber group also had higher struvite activity product in study 2. In both studies, urinary concentrations of HCl-insoluble sediment were higher in the starch group and fiber group. In the fiber group, a net loss of body calcium, phosphorus, and magnesium was detected in study 2. CONCLUSIONS AND CLINICAL RELEVANCE: Starch and fiber in diets potentially stimulate formation of struvite crystals. Hence, reducing dietary carbohydrate is desirable to prevent struvite urolith formation. In addition, a net loss of body calcium, phosphorus, and magnesium during feeding of the fiber diet suggests that dietary inclusion of insoluble fiber could increase macromineral requirements of cats. 相似文献
630.
Tamura M Nakagawa Y Shimizu H Yamada N Miyano T Miyazaki H 《The Journal of reproduction and development》2004,50(1):47-55
A number of endocrine and paracrine factors regulate the follicular growth and atresia, which are closely associated with granulosa cell survival and apoptosis. However, the molecular mechanisms underlying the intracellular events induced by these factors are poorly understood. Here, we describe the correlation of mitogen-activated protein kinase (MAPK) activities with granulosa cell survival and apoptosis, and the cellular functions of protein tyrosine phosphatases (PTPs) in these cells based on our recent data. MAPKs play key roles in various cellular responses because numerous extracellular stimuli are integrated into MAPKs. The protein phospho-Tyr level regulated by protein tyrosine kinases (PTKs) and PTPs is a major control mechanism for processes as diverse as cell survival, proliferation, differentiation, and metabolism. Although PTKs are critically involved in granulosa cell survival and proliferation, there are no reports indicating the roles of PTPs in the ovary except for ours. Information about MAPKs and PTPs in these cells will provide a basis for the understanding of the molecular mechanisms controlling the fate of follicles. 相似文献