The loss of activity of pyrethrum. II
- 1 April 1934
- journal article
- research article
- Published by Cambridge University Press (CUP) in The Journal of Agricultural Science
- Vol. 24 (4), 598-626
- https://doi.org/10.1017/s0021859600007279
Abstract
Summary: 1. The loss of activity of pyrethrum flowers and preparations has been studied.2. The degree of concordance between the content of pyrethrin I, as determined by the acid method, and the insecticidal value of pyrethrinised dusts, before and after exposure to air and artificial illumination, has been statistically examined. The pyrethrin I values, corrected for a small residual amount of extraneous matter, indicate fairly closely the degree of activity of the samples. The loss of pyrethrins on exposure has been traced out quantitatively.3. A comparison was made between two samples of pyrethrum flowers, one rich and the other poor in pyrethrins, in order to determine the degree of concordance between the pyrethrin I content and their toxicity. The pyrethrin I value as determined by the acid method, subject to a small correction, gave a good indication of the relative activities of the samples.This publication has 5 references indexed in Scilit:
- The Method of ProbitsScience, 1934
- Effect of Storage on Pyrethrum FlowersIndustrial & Engineering Chemistry, 1932
- The Loss of Toxicity of Pyrethrum Dusts on Exposure to Air and LightThe Journal of Agricultural Science, 1932
- Pyrethrin I and II: Their insecticidal value and estimation in Pyrethrum (Chrysanthemum cinebariaefolium). IThe Journal of Agricultural Science, 1929
- An Apparatus for testing the Toxic Values of Contact Insecticides under Controlled ConditionsBulletin of Entomological Research, 1924