Mephosfolan concentrations in hop ( Humulus lupulus L.) leaves and flowers after systemic uptake and the toxicity to caged aphids ( Phorodon hurnuli )

Publisher Website
Google Scholar
Abstract
The efficacy was investigated of various types of drench and granule application of mephosfolan in the control of the hop-damson aphid (Phorodon hurnuli) on hops. Toxicity in the younger, fully expanded leaves was measured by caging aphids on them for three days, and this was compared with the total leaf concentration of mephosfolan, determined by gas chromatography. Drench treatments had the great advantage of immediate uptake of the pesticide, otherwise there were no outstanding differences between the treatments. The interval before rapid uptake varied, and control could not be guaranteed within a given period after application. Various soil moisture factors are discussed in order to define this problem. The validity of using the younger, fully expanded leaves for toxicity assessments on hops of different sizes was apparently confirmed by chemical measurements, although the relationship between toxicity and total leaf concentration of mephosfolan changed over the useful life of a treatment.

This publication has 0 references indexed in Scilit: