T. T. Kozlowski , S. Sasaki, J. H. Torrie

Effects of temperature on phytotoxicity of monuron, picloram, CDEC, EPTC, CDAA, and sesone to young pine seedlings.

Kozlowski T. T., Sasaki S., Torrie J. H. (1967). Effects of temperature on phytotoxicity of monuron, picloram, CDEC, EPTC, CDAA, and sesone to young pine seedlings. Silva Fennica vol. 1 no. 3 article id 4752. https://doi.org/10.14214/sf.a14536

Abstract

The apparent toxicity of soil-incorporated monuron, picloram, CDEC, EPTC, CDAA, and sesone to young Pinus resinosa Ait. seedlings was studied over a temperature range of 10–30 °C in growth chambers. The herbicides were first applied to the surface of autoclaved soil at 1 1b/A and later mixed into the soil. Thereafter pine seeds were planted and subsequent seedling development was studied. The effect of CDEC, EPTC, CDAA, and sesone were also studied at dosages of 2 and 3 1b/A (soil surface basis).

Under the conditions of this study, picloram and monuron were persistent in the soil and toxic to pine seedlings, whereas CDEC, EPTC, CDAA, and sesone appeared to be non-toxic. However, the apparent lack of phytotoxicity of the latter group apparently was caused largely by lack of activation of sesone by autoclaving soil and large losses from the soil of CDEC, EPTC, and CDAA even before seeds were planted.

High toxicity of picloram and monuron was showed by reductions in seedling survival, total dry weight increment of plants, and dry weight increment of surviving seedlings. Various temperature regimes greatly affected growth of herbicide treated plants and controls. In control plants both high and low temperatures adversely affected seedling survival and dry weight more than shoot growth. Temperature extremes generally inhibited root growth more than shoot growth. The high temperatures, 25 and 30 °C, markedly enhanced phytotoxicity of picloram and muron.

The PDF includes a summary in Finnish.

Keywords
herbicides; toxicity; seedlings; Pinus resinosa; phytotoxicity

Published in 1967

Views 2011

Available at https://doi.org/10.14214/sf.a14536 | Download PDF