Insecticides In Solution Research Articles

Quantitative Analysis of Some Insecticides and Their Mixture in Agriculture by Using UV-Vis Spectrophotometer

We studied in this research how to find a method of estimating the quantity (Kinetically) of three kinds of Insecticide and their mixture, which are used in agriculture. The extracted insecticide from the polluted samples with these insect from air, soil, and the leaves of trees, have be used into the reaction with H2O2 and benzedine. The kinetic study of this reaction was formed in basic medium,( pH= 8.6), using UV. Spectra at (?= 420nm). The study showed that the reaction is the first order, and the speed of the reaction was used to estimate the concentration of insecticide in solution and mixture. The experiments of this study indicated that this method has the speed and efficiency for quantitatively estimating these insecticides in solution and mixture.

Quantitative Analysis of Some Insecticides and Their Mixture in Agriculture by Using UV-Vis Spectrophotometer

We studied in this research how to find a method of estimating the quantity (Kinetically) of three kinds of Insecticide and their mixture, which are used in agriculture. The extracted insecticide from the polluted samples with these insect from air, soil, and the leaves of trees, have be used into the reaction with H2O2 and benzedine. The kinetic study of this reaction was formed in basic medium,( pH= 8.6), using UV. Spectra at (?= 420nm). The study showed that the reaction is the first order, and the speed of the reaction was used to estimate the concentration of insecticide in solution and mixture. The experiments of this study indicated that this method has the speed and efficiency for quantitatively estimating these insecticides in solution and mixture.

Thermal decomposition and isomerization of cis-permethrin and beta-cypermethrin in the solid phase.

The stability to heart of cis-permethrin and beta-cypermethrin in the solid phase was studied and the decomposition products identified. Samples heated at 210 degrees C in an oven in the dark showed that, in the absence of potassium chlorate (the salt present in smoke-generating formulations of these pyrethroids), cis-permethrin was not isomerized, although in the presence of that salt, decomposition was greater and thermal isomerization occurred. Other salts of the type KXO3 or NaXO3, with X being halogen or nitrogen, also led to a considerable thermal isomerization. Heating the insecticides in solution in the presence of potassium chlorate did not produce isomerization in any of the solvents assayed. Salt-catalysed thermal cis-trans isomerization was also found for other pyrethroids derived from permethrinic or deltamethrinic acid but not for those derived from chrysanthemic acid. The main thermal degradation processes of cis-permethrin and beta-cypermethrin decomposition when potassium chlorate was present were cyclopropane isomerization, ester cleavage and subsequent oxidation of the resulting products. Permethrinic acid, 3-phenoxybenzyle chloride, alcohol, aldehyde and acid were identified in both cases, as well as 3-phenoxybenzyl cyanide from beta-cypermethrin. A similar decomposition pattern occurred after combustion of pyrethroid fumigant formulations.

The Toxicity of Some Insecticides to Army Worm

Abstract A series of experiments was carried out in order to determine the toxicity of various insecticides to Army Worm larvae. Known amounts of insecticide in solution were applied to larvae by means of a calibrated microcapillary. Approximate estimates of the median lethal doses of the compounds to larvae of Spodoptera exempta and S. triturata were obtained and an attempt has been made to correlate these with the recommended field dosage rates. The insecticides tested were DDT, Pyrethrins, ‘Dipterex’, dieldrin, ‘Toxaphene’, and ‘Telodrin’. The most toxic material to the larvae was ‘Dipterex’ which gave 100% kills at a dose level of 0.5 μg/g.

Techniques for the investigation of susceptibility to insecticides in larvae of the scarabaeid Costelytra zealandica (White)

Abstract Susceptibility to insecticides in larvae of Costelytra zealandica (White) has been studied in the laboratory by the topical application of insecticides in solution. Since the onset of mortality, especially that due to DDT, is slow, the loss or retention of the capacity for burrowing in loose soil was adopted as the criterion of effect. Response to DDT occurred over a wide range of dosage when acetone was employed as the solvent; with non-volatile solvents, olive oil or dioctyl phthalate, the range was less and log-dosage probit response lines were steeper. Conditions in the post-treatment period affected the slope of the regression line, which was steeper when the larvae were kept in a damp atmosphere than when they were covered with earth. Four main variants in technique are described, and their advantages discussed in relation to the detection and measurement of susceptibility or tolerance to DDT in larval populations, and possible analysis of these into genetically differing fractions.

FUNGITOXICITY OF CHLORINATED HYDROCARBON INSECTICIDES IN RELATION TO WATER SOLUBILITY AND VAPOR PRESSURE

Fungitoxicity, in terms of inhibition of mycelial growth, was demonstrated with eight chlorinated hydrocarbon insecticides by the culture plate bio-assay method. All of the dosage–response curves thus derived were bimodal rather than linear. Evidence is presented to show that the shape of these curves is governed by two physical properties of the compounds: water solubility (which was determined experimentally) and vapor pressure. The concentration of insecticide in solution governs the initial rise of each dosage–response curve which is extended to a peak because of supersaturation and is followed by a decline as normal saturation is regained. The concentration of toxicant vapor in contact with the organism governs the second rise in the curve to a level dependent on the vapor pressure of the compound. Lindane has a high degree of fungitoxicity because of its relatively high water solubility. Heptachlor, chlordane, and aldrin are also highly toxic because of their vapor pressures. DDT, methoxychlor, dieldrin, and endrin are weakly fungitoxic because of both low water solubility and low vapor pressure.

STATISTICAL ASPECTS OF THE INDEPENDENT JOINT ACTION OF POISONS, PARTICULARLY INSECTICIDES

Methods are described for discovering whether a mixture of two poisons is as toxic as predicted on the hypothesis of independent joint action. These include X2tests and a procedure for finding the maximum likelihood estimate of the coefficient of correlation in resistance to the poisons. The methods are illustrated using data from insecticidal tests.In the insecticidal tests, flour beetles, Tribolium castaneum Herbst, were sprayed with, or exposed to films of, different insecticides in solution in Shell oil P 31. The insecticides were pyrethrins, D.D.T., and B.H.C., singly and in pairs. The statistical analysis of the results showed that pyrethrins and D.D.T. could have acted independently both as films and as direct sprays; D.D.T. and B.H.C. could have acted independently as films but not as direct sprays; and B.H.C. and pyrethrins could not have acted independently either as films or as direct sprays.These findings are discussed, and it is concluded that independent action should be regarded as a special case of a more general type of joint action for which the term dissimilar is proposed. A general method of approach is suggested for the conception and development of hypotheses of the joint action of poisons.