Australian College of Veterinary Scientists     

Hugh McL Gordon 《Australian veterinary journal》1993,70(6):236-236

  相似文献   

Ontario. Meningoencephalitis associated with bacterial kidney disease in salmonids   总被引：1，自引：1，他引：0       下载免费PDF全文

Speare DJ  Ostland VE  Ferguson HW 《The Canadian veterinary journal. La revue veterinaire canadienne》1991,32(2):117

  相似文献   

Juvenile lymphoma in a Holstein heifer          下载免费PDF全文

Charlton KW  Ferguson WG 《The Canadian veterinary journal. La revue veterinaire canadienne》1990,31(6):459

  相似文献   

Melanin biosynthesis in Pyricularia oryzae: Site of tricyclazole inhibition and pathogenicity of melanin-deficient mutants     

Charles P. Woloshuk  Hugh D. Sisler  Maria Chrysayi Tokousbalides  Samson R. Dutky 《Pesticide biochemistry and physiology》1980,14(3):256-264

Tricyclazole (5-methyl-1,2,4-triazolo[3,4-b]benzothiazole) inhibits melanin synthesis in Pyricularia oryzae at concentrations less than 0.01 μg/ml. The primary site of inhibition in the biosynthetic pathway occurs between scytalone and vermelone. Accumulation of several metabolites derived from melanin precursors along branch pathways is associated with inhibition of melanin biosynthesis. At low tricyclazole concentrations (0.01–1 μg/ml), predominant accumulation of 2-hydroxyjuglone and 3,4-dihydro-3,4,8-trihydroxy-1-(2H)-naphthalenone (3,4,8-DTN) occurs as a result of the primary block between 1,3,8-trihydroxynaphthalene and vermelone. As the concentration of tricyclazole is increased from 1 to 10 μg/ml, flaviolin accumulation is markedly enhanced, whereas that of 3,4,8-DTN and 3,4-dihydro-4,8-dihydroxy-1-(2H)-naphthalenone is depressed, indicating possible secondary sites of inhibition in the main and branch pathways. Five melanin-deficient mutants of P. oryzae that phenotypically resemble the tricyclazole-treated wild-type strain were nonpathogenic or rarely infected two rice varieties. Three of the mutants studied were genetically defective in the melanin biosynthetic pathway at the site blocked by tricyclazole in the wild type. The wild-type strain converted both scytalone and vermelone to melanin; whereas the three mutants and the tricyclazole-treated wild type converted only vermelone to melanin. The data suggest a relationship between melanin biosynthesis and pathogenicity in P. oryzae.  相似文献   

Antifungal mode of action of triforine     

James L. Sherald  Hugh D. Sisler 《Pesticide biochemistry and physiology》1975,5(5):477-488

Rapidly growing mycelia of Aspergillus fumigatus treated with 10 μg/ml triforine (N,N′-bis-(1-formamido-2,2,2-trichloroethyl)-piperazine) showed little or no inhibition in dry weight increase prior to 2 h. By 2.5–3 h, triforine inhibited dry weight increase by 85%. The effects of triforine on protein, DNA, and RNA syntheses corresponded to the effect on dry weight increase both in time of onset and magnitude. Neither glucose nor acetate oxidation were inhibited by triforine.Ergosterol synthesis was almost completely inhibited by triforine even in the first hour after treatment. Inhibition of ergosterol synthesis was accompanied by an accumulation of the ergosterol precursors 24-methylenedihydrolanosterol, obtusifoliol, and 14α-methyl-Δ^{8, 24 (28)}-ergostadienol. Mycelia treated with 5 μg/ml of triarimol (α-(2,4-dichlorophenyl)-α-phenyl-5-pyrimidinemethanol) also accumulated the same sterols as well as a fourth sterol believed to be Δ^{5, 7}-ergostadienol.Identification of 4,4-dimethyl-Δ^{8, 24 (28)}-ergostadienol in untreated mycelia indicates that the C-14 methyl group is the first methyl group removed in the biosynthesis of ergosterol by A. fumigatus. The lack of detectable quantities of 4,4-dimethyl-Δ^{8, 24 (28)}-ergostadienol in triforine or triarimol-treated mycelia and the accumulation of C-14 methylated sterols in treated mycelia suggests that both fungicides inhibit sterol C-14 demethylation. The accumulation of Δ^{5, 7}-ergostadienol in triarimol-treated mycelia further implies that triarimol also inhibits the introduction of the sterol C-22(23) double bond.Two strains of Cladosporium cucumerinum tolerant to triforine and triarimol were also tolerant to the fungicide S-1358 (N-3-pyridyl-S-n-butyl-S′-p-t-butylbenzyl imidodithiocarbonate).  相似文献   

A coat protein transgene from a Scottish isolate of potato mop-top virus mediates strong resistance against Scandinavian isolates which have similar coat protein genes     

Brian Reavy  Maria Sandgren  Hugh Barker  Pekka Heino  Per Oxelfelt 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(9):829-834

Resistance tests were made on seedlings of transformed lines of Nicotiana benthamiana which contain a transgene encoding the coat protein (CP) gene of a Scottish isolate of potato mop-top virus (PMTV). This transgene has been reported to confer strong resistance to the PMTV isolate from which the transgene sequence was derived and also to a second Scottish isolate. Plants of lines of the transgenic N. benthamiana were as resistant to two Swedish and two Danish PMTV isolates as to a Scottish isolate, and of five lines tested, greater than 93.5% of transgenic plants were immune. The coat protein gene sequences of these four Scandinavian isolates were very similar to those of the two Scottish isolates. The greatest divergence between the isolates was three amino acid changes and there was less than 2% change in CP gene nucleotide sequence. It is concluded that the PMTV CP transgene used in these experiments could confer resistance against isolates from different geographical areas because it is becoming apparent that the CP genes of PMTV isolates are highly conserved.  相似文献   

Level and Timing of Nitrogen Fertilizer Application to Early and Semi-early Potatoes (Solanum tuberosum L.) Grown with Irrigation on Light Soils in Norway     

Hugh Riley 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):122-134

Trials were performed with early and semi-early potatoes to test the effects of nitrogen (N) fertilizer level (0-160 kg N ha^-1) and timing (all at planting versus half then and half either soon after emergence or 3 weeks later). All seven trials with earlies were irrigated as required, whilst different irrigation regimes (moderate versus intensive) were compared in two trials with semi-earlies. No benefit was derived from splitting the N application. Haulm growth and N uptake increased in all cases almost linearly up to the highest N level, but tuber yield did not respond in the same way. The optimum N level was 80 kg N ha^-1 for a yield of 15 Mg ha^-1, rising to 120 kg N ha^-1 for a yield of 40 Mg ha^-1. Tuber quality was lowered by the use of excess N fertilizer, particularly in the case of earlies. The quantity of mineralised N present in the soil after harvest rose sharply with above optimum fertilizer use, and the amount of N present in crop residues also increased. The likely leaching after early potatoes was estimated to be up to 80 kg N ha^-1. The proportion of fertilizer N which was not accounted for in either tuber yield, crop residues or mineral N in soil was 26% in earlies and 38% in semi-earlies.  相似文献   

Atmosphere. Forecasting hurricane intensity and impacts     

Willoughby HE 《Science (New York, N.Y.)》2007,315(5816):1232-1233

  相似文献   

Potential of UV-C for management of two-spotted spider mites and thrips in Florida strawberry     

Joseph D. Montemayor  Hugh A. Smith  Natalia A. Peres  Sriyanka Lahiri 《Pest management science》2023,79(2):891-898

  相似文献   

Hybridisation in kiwi (Apteryx; Apterygidae) requires taxonomic revision for the Great Spotted Kiwi     

Lara D.Shepherd  Alan J.D.Tennyson  Hugh A.Robertson  Rogan M.Colbourne  Kristina M.Ramstad 《中国鸟类》2021,(2):195-207

Background: Kiwi (Apteryx spp.) are flightless ratites from New Zealand whose numbers and distributions have declined following human arrival. Some of the kiwi ...  相似文献