Novel chemical approaches to crop protection: Needs and solutions

Abstract

The examination of conventional chemical methods of crop protection suggests problems and opportunities that call for alternative approaches. The need for such novel treatments is considered in relation to damaging organisms not controlled by traditional pesticides, biological availability, resistance, selectivity and compatibility with other methods within the concept of integrated pest, disease or weed management. Analysis of these needs and opportunities suggests directions in which to seek novel chemical agents including those which can attack vital processes not previously exploited as target sites, the modification of physicochemical properties determining mobility and availability, chemical formulation, symptom suppression and the manipulation of chemically‐mediated processes other than direct toxic action, and the use of agents which extend the usefulness of existing toxic agents. Examples illustrating these approaches are discussed.

Effects of essential oils from the Brazilian pepper tree, eucalyptus and citronella on brassica aphids Brevicoryne brassicae and Myzus persicae (Hemiptera: Aphididae) and their parasitoid Diaeretiella rapae (Hymenoptera: Braconidae)

“…Among the EOs tested, C. winterianus showed superior efficiency in causing the death of brassicas aphids. According to Graham-Bryce (1983), various species may have differences in susceptibility to essential oils, since these characteristics are attributed to physiological or biochemical differences, such as cuticle permeability, detoxifying enzymatic activity and sensitivity related to toxic damage at the target site.…”