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991.
V. ANJAIAH D. V. R. REDDY S. K. MANOHAR R. A. NAIDU Y. L. NENE A. S. RATNA 《Plant pathology》1989,38(4):520-526
A potyvirus that induced stunting and a characteristic bushy appearance at the apical region, due to proliferation of terminal branches with narrowed, reduced and deformed leaflets, was isolated from chickpea in India. The virus was sap-transmissible to 14 species of Chenopodiaceae, Leguminosae, Solanaceae and Malvaceae; Chenopodium amaranticolor was a good local lesion host. Virus particles, trapped by immunosorbent electron microscopy and stained with uranyl acetate, were 710 ×10 nm long. Purified virus preparations contained a single polypeptide species of 32,500 Da and one nucleic acid species of 3.1 · 106 Da. The virus was serologically related to soybean mosaic, azuki bean mosaic and peanut mottle viruses but not to clover yellow vein, pea seed-borne mosaic and bean yellow mosaic viruses.
On the basis of these properties, the virus was identified as a previously undescribed potyvirus in chickpea, for which the name chickpea bushy dwarf virus is proposed. 相似文献
On the basis of these properties, the virus was identified as a previously undescribed potyvirus in chickpea, for which the name chickpea bushy dwarf virus is proposed. 相似文献
992.
T. Limonard M. A. Ruissen 《European journal of plant pathology / European Foundation for Plant Pathology》1989,95(1):129-135
Present conditions of high inputs and narrow rotations render the importance of vesicular-arbuscular mycorrhiza (VAM) in arable farming in the Netherlands rather low. Changes expected in the near future under the influence of economic pressures and environmental problems may change this situation. This is discussed in the light of some such expected changes in Dutch arable farming. 相似文献
993.
A series of substituted 4-methylcoumarins was synthesised and the members tested for their toxicity towards mycelial growth of seven phytopathogenic fungi in culture. Rhizoctonia solani, Alternaria alternata and Fusarium solani exhibited maximum sensitivity to these compounds whereas Pythium aphanidermatum, Colletotrichum falcatum, Drechslera oryzae and Macrophomina phaseolina were relatively less sensitive. 6-Ethyl-3-n- propyl-7-hydroxy4-methylcoumarin ( I ) was relatively toxic towards all fungi except C. falcatum, P. aphanidermatum and M. phaseolina. The 6-n-butyl ( III ) and 6-(1, 1, 3, 3-tetramethylbutyl) ( VI ) derivatives were highly toxic to R. solani with EC50, values of lμg ml?1. 相似文献
994.
Of the 44 currently accepted species of Phytophthora, 18 have been reported in the Mediterranean area. The status of each is briefly reviewed. On citrus, P. citrophthora and P. nicotianae var. parasitica are mainly responsible for foot rot and gummosis, and in addition P. hibernalis, P. syringae, P. cifricola and P. cactorum for brown rot of fruits. The incidence of these species is closely linked to their temperature requirements. The use of sour orange as a resistant rootstock has long provided satisfactory control of foot rot and gummosis, while chemical treatments are effective against brown rot. However, there are indications that, with changingcultural practices, the resistance of sour orange is less well expressed, and the species is incidentally also susceptible to citrus tristeza closterovirus. Alternative rootstocks are therefore being sought. 相似文献
995.
Using counterimmunoelectrophoresis and ELISA tests the dynamics of antibody production in serum of mice experimentally infected with Toxascaris leonina was studied. The production of antibodies using both tests has already been detectable in serum of mice from 7 days post infection (DPI) and their level persisted till the end of the experiment, i.e. till 77 DPI. The most positive were reactions of sera with Antigens 1 and 3. 相似文献
996.
V Bukva 《Folia parasitologica》1990,37(1):81-91
Evidence of three distinct Demodex species parasitizing the sheep is given for the first time. A newly distinguished Demodex sp. is described, and diagnostic characters are compared for Demodex ovis Hirst, 1919, D. aries Desch, 1983, and Demodex sp. Information on prevalence, distribution in the tissues, and pathogenicity of these three Demodex species in 132 head of sheep in Czechoslovakia is presented, with a review of such data published to date. 相似文献
997.
A new genus, Ornithocapillaria gen. n., belonging to the family Capillariidae and subfamily Baruscapillariinae is described and its diagnosis is given. The type species of the genus is Ornithocapillaria ovopunctata (Linstow, 1873) comb. n., other species are O. cylindrica (Eberth, 1863) comb. n., O. quiscali (Read, 1949) comb. n., and O. picorum (Rudolphi, 1819) comb. n. The new genus is characterized by a relatively large membranous pseudobursa, shape of processes supporting pseudobursa, and presence of a vulval appendage in female. It includes only species parasitic in the intestine of birds of the orders Passeriformes, Falconiformes, Strigiformes, and Piciformes. 相似文献
998.
A new entomopathogenic species of the genus Tolypocladium, T. terricola is described from a soil sample from Finalnd. From other known Tolypocladium species, T. terricola differs in morphology, production of secondary metabolites and possession of relatively strong mosquitocidal activity. The fungus is characterized by broad oval conidia (2.5 x 2 microns) with one pointed end which are produced in grape-like clusters, and are not firmly adherent. When treated with T. terricola, mosquito larvae show typical features of intoxication characterized by the concentration of larvae in the centre of cup, hanging by their siphons on the surface. 相似文献
999.
The life cycle of Rubenstrema opisthovitellinum So?tys, 1954, a parasite of shrews, is elucidated. The following developmental stages are described in detail: daughter sporocyst, cercaria, metacercaria, and adult. The freshwater snail Planorbarius corneus was found to be the first intermediate host in nature. The metacercariae were obtained from the larvae of mosquitoes Culex molestus and only exceptionally from snails Physa acuta. The adults were obtained from the small intestine of hamsters Mesocricetus auratus. The life cycle and the larval stages of R. opisthovitellinum are described for the first time. 相似文献
1000.
Intestinal parasites: a study of human appendices 总被引:2,自引:0,他引:2
Histological sections of 414 appendices were examined parasitologically. Enterobius vermicularis was found in 8.7%, eggs of Ascaris lumbricoides in 0.5%, trophozites of Dientamoeba fragilis in 4.8%, Endolimax nana in 2.2%, Entamoeba coli in 1% and cysts of Giardia intestinalis in 1.9% of cases. Appendicopathies associated with Enterobius were most frequent in the age group from 6 to 10 years (24.3%) and from 21 to 25 years (12.2%). Patients older than 15 years were practically women only. Dientamoeba was most frequent in the age group from 11 to 15 years (11.3%). In women D. fragilis was three times more frequent than in men. The coincidence of D. fragilis and E. vermicularis infections was 50%. No interactions were seen between the protozoans in the contents of the appendix and its mucous membrane. Statistical evaluation indicates possible etiologic role of E. vermicularis in the occurrence of acute appendicities. D. fragilis appears to be the most common intestinal protozoan parasite in Bohemia. 相似文献