The Phytotoxicity of Some Herbicides in Field and Pot Experiments in Relation to Soil Properties

Abstract

Summary. The phytotoxicities in a number of soils of lenacil, linuron, prometryne and simazine to two indicator plants were determined in field and glasshouse experiments. The results were compared with estimates of the adsorption capacity of the soils obtained by two methods using dimethylaminobenzaldehyde as a model adsorbate. The possible influence of other soil properties was also considered. One of the adsorption measurements had some predictive value for glasshouse behaviour but was not markedly superior to soil organic carbon content for this purpose. None of the factors studied was usefully correlated with field performance. Results from field experiments in spring were poorly correlated with those from similar experiments in autumn. Neither set of field results related closely to those obtained in the glasshouse. It is concluded that the influence of climate was more important than that of soil type. La phytotoxiciti de quelquts herbicides dans des experiences en pots et en plein champ, en relation avec les propriétés du sol

Fluometuron Adsorption-Desorption Equilibria in Soil

“…An important factor affecting availability and subsequent phytotoxicity of herbi cides is adsorption onto soil colloids (7,13,18,19,20,22). Although phenylurea herbicide adsorption has been demon strated in pure silicate clay systems (2, 6), there is strong correlative evidence that the organic fraction of the soil is of primary importance in adsorption (5,10,11,12,14,15,19).…”

Soil Properties Influencing Soil Adsorption and Phytotoxicity of Atrazine and Simazine in Nine Danish Soils

“…whereas climatic factors were of only minor significance. However, Hance et al (1968) found that soil organic matter was significantly correlated with 3 -793832 siniazine phytotoxicity in greenhouse experiments but provided a poor estimate of phytotoxicity in field trials, where climatic factors seemed to be more important than soil type. Under Danish conditions Petersen (1970) found a negative relation bet\vecn the leachability of simazine and soil organic matter content.…”

Availability of atrazine to plants in different soils

“…The specimen tubes were weighed periodically and when they had lost I g water, 1 ml was pipetted onto the surface. The plants from duplicate pots were harvested after 4,7,9,11,14,16,18 and 21 days and the amounts of herbicide accumulated were determined as previously described. The contents of six specimen tubes were transferred to centrifuge tubes at intervals during the experimental period.…”