| 单词 | pyrethrin i |
| 释义 | > as lemmaspyrethrin I Originally: an insecticidal powder produced by grinding the flower heads of the plant pyrethrum, Tanacetum cinerariifolium. In later use also: any of a class of insecticidal terpenoid esters which are obtained from the seed cases of pyrethrum and related plants, or prepared synthetically; spec. either of two such compounds (in full pyrethrin I, pyrethrin II) which comprise the active ingredients of pyrethrum powder. ΘΚΠ the world > physical sensation > use of drugs and poison > poison > [noun] > insecticide or pesticide acaricide1841 pyrethrum1876 benzene hexachloride1884 systemic1893 alphachloralose1894 pyrethrin1896 hexachlorethane1898 pesticide1933 bomb1944 bug juice1944 adulticide1945 miticide1946 chlordane1947 HCH1947 lindane1949 allethrin1950 Pybuthrin1951 isodrin1953 monosulfiram1953 mirex1962 naled1963 propoxur1964 methiocarb1966 carbofuran1968 aldicarb1969 pirimicarb1970 tickicide1971 methoprene1974 1896 Daily Republican (Decatur, Illinois) 30 Jan. 8/4 There is a powder called pyrethrin that when sprinkled will kill them and is not injurious to the cabbages. 1928 H. Martin Sci. Princ. Plant Protection 128 Staudinger and Ruzicka..isolated two esters to which they gave the name ‘Pyrethrine I’ and ‘Pyrethrine II’. 1951 H. H. Shepard Chem. & Action Insecticides viii. 146 The pyrethrin content is higher in flowers produced in cool mountain valleys than where the mean temperature is high. 1971 Nature 15 Oct. 441/1 Six esters are found in the pyrethrum of which the most important and plentiful are known as pyrethrins I and II. 1995 Org. Gardening Jan. 20/1 We never recommend using toxic insecticides, even the plant-derived ‘botanical’ ones like rotenone and pyrethrin which have been accepted by some growers. < as lemmas |
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