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71.
Multiple, dermal and subcutaneous nodules developed in a young female Manchester Terrier dog that had a chronic history of superficial dermatophytosis. Skin biopsy specimens of the nodules revealed granulomatous inflammation in the deep dermis and subcutis with branching fungal organisms. Cultures of multiple biopsy specimens from the nodules all yielded Trichophyton mentagrophytes. The lesions in this dog were similar to granulomatous dermatophytosis, a skin disease that has been reported in Persian cats and one Yorkshire Terrier dog. 相似文献
72.
Dry mycelium (DM) of killedPenicillium chrysogenum and its water extract (DME) were used to induce resistance in cotton plants againstFusarium oxysporum f.sp.vasinfectum (Fov). Results showed that the efficacy of either DM or DME in controlling the disease depends on both the concentration and the
mode of application. DM amended to the soil at 0.25–2% (w/w) provided 32–75% protection againstFov. Soil drench with 2–5% DME (w/v) and pre-sowing seed soakage with 5–10% DME provided 51–77% and 28–35% protection against
the wilt disease, respectively, whereas no protection was obtained with foliar sprays of 1–10% DME. DM and its water extract
had no direct antifungal activity on growth ofFov in vitro, suggesting that disease control with DM or DME resulted from the induction of natural defense mechanisms in the cotton plants.
Soil drench with 5% DME was as effective as 2% DM powder in inducing resistance againstFov, implying that the resistance-inducing substances were mostly water-soluble. Four cotton cultivars with various genetic resistance
levels againstFov were tested at the seedling stage: two resistant ‘Pima’ cultivars and two susceptible ‘Acala’ cultivars. The level of protection
achieved in the two susceptible cultivars with DME was equal to, or higher than, that of the two resistant cultivars treated
with water. Innate and induced peroxidase activity in cotyledons or hypocotyls and roots coincided with the level of genetic
resistance and DME-induced resistance, respectively. Based on our results, an integrated control strategy ofFov with both genetic resistance and induced resistance is suggested. 相似文献
73.
Five fast-neutron-derived mutants were isolated from the wheat line Hobbit 'sib' that show enhanced field resistance towards Puccinia striiformis f.sp. tritici , the causal agent of yellow rust. Subsequent testing showed the yellow rust resistance phenotypes to differ between mutants, to be expressed at different growth stages and, in some cases, to show an isolate interaction. Three mutants, I3-48, I3-49 and I3-54, exhibited an enhanced yellow rust resistance phenotype from the third seedling leaf onwards, while mutants I3-27 and I3-30 did not show an altered yellow rust phenotype until later growth stages. Additional resistance for brown rust (causal agent Puccinia triticina ) was identified in mutants I3-27, I3-30, I3-48 and I3-49, and for powdery mildew caused by Blumeria graminis f.sp. tritici in mutants I3-27, I3-30, I3-48 and I3-54, although in some cases the resistance was isolate-specific. 相似文献
74.
Mamoru Satou Kazufumi Nishi Masaharu Kubota Michiko Fukami Hideaki Tsuji Kees van Ettekoven 《Journal of General Plant Pathology》2006,72(3):193-194
The races for the causal agent of spinach downy mildew Peronospora farinosa f. sp. spinaciae were identified by inoculation of race-differential cultivars. One isolate was identified as Pfs:5s and the others belonged
to a new race. This is the first report of race Pfs:5 and another new race in Japan. 相似文献
75.
四种鲜牛肝菌成分分析 总被引:1,自引:0,他引:1
采用原子吸收分光光度法、比色法等方法对美味牛肝菌、华美牛肝菌、美柄牛肝菌和绒柄牛肝菌4种鲜牛肝菌的粗蛋白、粗脂肪、矿质元素、有害元素的含量进行测定.结果表明,4种鲜牛肝菌中,粗蛋白、粗脂肪、总糖和粗纤维的含量范围分别是4.38%~5.42%、2.47%~3.07%、1.26%~3.85%、1.23%~1.56%;矿质元素铁、锌、钙的含量范围分别是19.62~37.96mg/kg、6.53~9.67mg/kg、146.23~298.02mg/kg;总砷含量未检出,有害元素总汞、铅、镉的含量范围分别是0.06~0.73mg/kg、0.4~0.62mg/kg、0.075~0.105mg/kg.结论:这4种野生鲜牛肝菌含有丰富的营养成分,但华美牛肝菌、美柄牛肝菌中总汞含量较高,值得关注. 相似文献
76.
福建省香蕉枯萎病菌硝酸盐营养突变体的营养体亲和性测定 总被引:5,自引:0,他引:5
Fourteen strains of Fusarium oxysporum f. sp. cubense were induced to produce 146 nitrate-nonutilizing(nit) mutants on a chlorate-containing medium. Among them, there were 117 nit1 mutants(80.14%), 17 nit3 mutants(11.64%) and 12 nitM mutants(8.22%). These strains were divided into two vegetative compatibility groups(VCGs) by the vegetative compatibility tests. Twelve strains of F. oxysporum f. sp. cubense from Musa AAA belonged to VCG1, two trains from Musa ABB belonged to VCG2. 相似文献
77.
香蕉枯萎病拮抗菌的筛选及其作用机制研究 总被引:15,自引:0,他引:15
通过分离和筛选,从香蕉园或者其他果园的土壤中分离获得13株对香蕉枯萎病菌(Fusarium oxysporum f.sp.cubense)具有抑制作用的拮抗菌,并对部分拮抗菌抑制病菌菌丝生长和孢子萌发进行了试验。结果表明,拮抗菌株d4、d5、B3和p发酵液对香蕉枯萎病菌生长具有显著的抑制作用,在平板上产生的抑菌圈直径为21.75~34.75 mm,抑菌效果具有持续稳定性,对孢子萌发的抑制率为90.49%~97.18%;拮抗菌对病菌的作用表现为对菌丝的消融、菌丝细胞的泡囊化、抑制病菌分生孢子的萌发、孢子芽管的扭曲。 相似文献
78.
轮纹病菌侵染对不同抗性苹果品种膜透性及防御酶的影响 总被引:3,自引:2,他引:3
对轮纹病菌Botryosphaeria berengriana f.sp.piricola侵染3个不同抗性苹果品种枝条后的细胞膜透性及防御酶系的变化进行了测定,以分析其与抗性的关系。结果表明,接种后38天内,3个品种电解质渗出率均有先升后降的趋势,鸡冠、国光和富士电解质渗出率变化的峰值分别为8.1%、12.2%和18.4%,抗病品种鸡冠的变化明显低于感病品种富士和国光。接种后35天内,苯丙氨酸解氨酶、超氧化物歧化酶、过氧化物酶和多酚氧化酶也表现为先升后降的趋势,且抗病品种的峰值出现较晚。抗病品种鸡冠的苯丙氨酸解氨酶、超氧化物歧化酶和过氧化物酶活性变化峰值分别为234、50.88U·g-1FW·h-1和14.22U·g-1FW·min-1,高于国光和富士,而多酚氧化酶活性变化的峰值为37.78U·g-1FW·min-1,低于感病品种国光和富士。 相似文献
79.
Zucchini lethal chlorosis virus (ZLCV) is a tospovirus that infects species of cucurbits in Brazil and is transmitted by the thrips Frankliniella zucchini. The purpose of the present work was to evaluate the reaction of seven species of cucurbits to infection with ZLCV under field and greenhouse conditions in Piracicaba County, SP. In the field experiment, ZLCV infection occurred naturally. In the greenhouse, plants were mechanically inoculated with ZLCV at the cotyledonal stage. Evaluations were based on symptoms expression and detection of the virus by PTA-ELISA. The percentages of infected plants for field and greenhouse assays, respectively, are indicated in parenthesis for each species/cultivar: Cucurbita pepo var. Caserta (72.9 and 70.7); C. maxima var. Alice (16.0 and 10.4); C. maxima var. Exposição (0.0 and 0.0); C. moschata var. Menina Brasileira (29.2 and 18.2); C. maxima × C. moschata hybrid Takaiama (63.4 and 42.7); Citrullus lanatus var. Crimson Sweet (25.0 and 25.0); Cucumis sativus var. Safira (14.3 and 41.2); and C. anguria (21.4 and 22.7). 相似文献
80.
Yuuri Hirooka Takao Kobayashi Jun Takeuchi Tsuyoshi Ono Yasunori Ono Keiko T. Natsuaki 《Journal of General Plant Pathology》2007,73(5):330-335
A ring spot disease of Aloe vera was found on leaves of potted seedlings of Aloe vera in Hachijojima and Chichijima Islands, Tokyo. From tissue of ring spot lesions, a fungus producing Fusarium-type conidia was consistently isolated. After 1 month, reddish perithecia of nectriaceous fungus had formed on the colonies
of this isolate on PDA. These nectriaceous and Fusarium fungi were identified as Haematonectria haematococca and Fusarium sp., respectively. From a single ascospore isolation, the former was confirmed to be the teleomorph of the Fusarium sp. Typical ring spot lesions were reproduced by artificial inoculations using single ascospore and single conidium isolates.
Inoculations of five species of genus Aloe revealed that they were highly susceptible except for A. arborescens. This is the first report of a disease on Aloe caused by H. haematococca (anamorph: Fusarium sp.) in Japan, and it was named aloe ring spot. 相似文献