Search results for "DCMU"
showing 6 items of 6 documents
Use of chlorophyll fluorescence induction kinetics to study translocation and detoxication of DCMU-type herbicides in plant leaves
1984
Transient levels of the fluorescence induction rise were used to quantify partial photosynthesis inhibition by DCMU -type herbicides in whole leaves. Assays in different crop or weed species showed a good accuracy in measurements (generally, variation was lower than 5%). This technique was applied to the problem of varietal selectivity of wheat towards chlortoluron.
Effects of Acifluorfen-methyl on cucumber cotyledons : porphyrin accumulation
1988
Abstract The nitrodiphenyl ether herbicide acifluorfen-methyl and the pyridine derivative LS 82-556 induce porphyrin accumulation in green cucumber cotyledons. When experiments are done with intact plants absorbing the herbicide through the roots, that accumulation is light-dependent. 3-(3,4-Dichlorophenyl)-1,1-dimethylurea (DCMU) which prevents cellular damages under these conditions (M. Matringe and R. Scalla, Pestic. Biochem. Physiol. 26 , 150 (1986), also inhibits porphyrin accumulation. In contrast, when detached cotyledons are cut into pieces and floated on herbicide solutions, porphyrins accumulate in the dark. Accordingly, DCMU does not inhibit porphyrin accumulation or protect the …
Über den Ureidstoffwechsel beim Laubmoosprotonema von Funaria hygrometrica L. (Sibth.)
1973
Summary 1. Allantoin and allantoic acid were about 6 % of the total nitrogen content of moss protonema (Funaria hygrornetica L.). 2. The level of endogenous allantoin depends on the spectrum colour of the irradiation. The peaks coincide with the peaks of a chlorophyll absorption spectrum from a methanolic extract of moss protonema. 3. The total amount of allan to in consists of two parts. One part is supplied by metabolism in darkness but the main one depends on light. Green- and far red light are “physiological dark conditions” for the moss protonema. In the dark ureide degradation comes to an end with allantoic acid. There are only traces of urea. 4. The coinciding correlations between th…
The redox state regulates RNA degradation in the chloroplast of Chlamydomonas reinhardtii.
1999
Abstract A Chlamydomonas reinhardtii chloroplast transformant, designated MU7, carrying a chimeric (rbcL promoter: β-glucuronidase [GUS]:psaB 3′ end) gene whose transcripts have been found previously to be unstable in light (half-life of 20 min in light as opposed to a half-life of 5 h in the dark), was used to study the role of electron transport and of the redox state in the degradation of chloroplast transcripts in the light. Blocking photosynthetic electron transport with 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) prevented the light-dependent breakdown of the pool of GUS transcripts in MU7 cells. Diamide, an oxidizing agent, caused a measurable delay in the degradation of GUS trans…
Changes in yield ofin-vivo fluorescence of chlorophyll a as a tool for selective herbicide monitoring
1993
Triazines and derivatives of phenylurea, which are often found in outdoor water samples, induce specific changes in the yield of thein-vivo chlorophyll α-fluorescence of PSII. These changes are correlated quantitatively with the concentration of the herbicides and can therefore be used to set-up a low-price monitor system. In order to detect selectively the herbicide-sensitive part of the fluorescence emission a pulse amplitude modulated fluorimeter was used. The bioassay system was optimised with respect to test organism, growing and measuring conditions. The relationship between fluorescence yield and herbicide concentrations were experimentally determined for the triazines atrazine and s…
Über den Ureidstoffwechsel beim Laubmoosprotonema von Funaria hydrometrica L. (Sibth.)1)1)Herrn Prof. Dr. Dr. Kurt Mothes zum 75. Geburtstag gewidmet.
1975
Summary The activity of allantoinase (EC 3.5.2.5) is influenced by light and darkness. The extracts of dark-grown moss protonema showed a very higher enzyme activity than the extracts of light-grown plants. The allantoinase activity was increased by light-dark and decreased by dark-light transitions. DMAP mimicked light effects by stabelizing the charakteristic light depending enzyme avctivities in the dark. The inhibitors DCMU, DNP and CCCP increased the enzyme activity of light-grown moss protonema, to some extend they induced a “physiological dark condition”.