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《Journal of Cereal Science》2005,42(2):225-231
Wheat line L88-31 was transformed with a gene encoding an extended form of subunit 1Dx5 to study the relationship between subunit size and the effect on dough mixing properties. Four transgenic lines were recovered, one of which expressed a truncated form of the protein with mobility between those of the wild type and extended subunits. Comparison of the Mixograph profiles and gluten protein compositions with those of the control lines and a line expressing the wild type subunit 1Dx5 transgene showed that two of the transgenic lines had poor mixing properties and that this was associated with co-suppression of HMW subunit gene expression. The other two transgenic lines had improved mixing properties (measured as increased mixing time) and this was associated with increased proportions of large glutenin polymers. None of the transgenic lines expressing the extended form of the 1Dx5 subunit showed the ‘overstrong’ mixing properties exhibited by transgenic lines expressing the wild type 1Dx5 transgene. 相似文献
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The uptake of 2,4,5-T by spines of gorse (Ulex europaeus L.) was limited and not enhanced when picloram was added to the application solution. Translocation of 2,4,5-T in 6-month-old cuttings after treatment of a single spine or lateral branch was poor. The most significant accumulation of translocated herbicide occurred in stem tissue, with lesser amounts detected in root tissues, root nodules, stem apices and flowers. Untreated lateral branches or spines accumulated minimal amounts of herbicide. The pattern and extent of distribution of 2,4,5-T was not increased by addition of picloram. The lack of efficient control of gorse by 2,4,5-T can largely be attributed to its inadequate uptake and lack of true systemic translocation. 相似文献
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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
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