From Metchnikoff to Monsanto and beyond: The path of microbial control

Abstract

In 125 years since MetchnikoV proposed the use of Metarhizium anisopliae to control the wheat cockchafer and brought about the Wrst Weld trials, microbial control has progressed from the application of naturalists' observations to biotechnology and precision delivery. This review highlights major milestones in its evolution and presents a perspective on its current direction. Fungal pathogens, the most eye-catching agents, dominated the early period, but major mycological control eVorts for chinch bugs and citrus pests in the US had questionable success, and interest waned. The discoveries of Bacillus popilliae and Bacillus thuringiensis began the era of practical and commercially viable microbial control. A program to control the Japanese beetle in the US led to the discovery of both B. popilliae and Steinernema glaseri, the Wrst nematode used as a microbial control agent. Viral insect control became practical in the latter half of the 20th century, and the Wrst registration was obtained with the Heliothis nuclear polyhedrosis virus in 1975. Now strategies are shifting for microbial control. While Bt transgenic crops are now planted on millions of hectares, the successes of more narrowly deWned microbial control are mainly in small niches. Commercial enthusiasm for traditional microbial control agents has been unsteady in recent years. The prospects of microbial insecticide use on vast areas of major crops are now viewed more realistically. Regulatory constraints, activist resistance, benign and eYcacious chemicals, and limited research funding all drive changes in focus. Emphasis is shifting to monitoring, conservation, integration with chemical pesticides, and selection of favorable venues such as organic agriculture and countries that have low costs, mild regulatory climates, modest chemical inputs, and small scale farming. Published by Elsevier Inc.

Nobel laureate Ilya I. Metchnikoff (1845-1916). Life story and scientific heritage

“…Lactic acid products containing the bacteria lactobacillus bulgaricus were recommended by him as healthy food supplements, that was the first introduction of the concept of probiotics [42]. He also expressed the idea of biological plant protection [43].…”

An Overview on the Crystal Toxins from <i>Bacillus thuringiensis</i>

“…But it was formally characterized by Ernst Berliner from diseased flour moth caterpillars (Ephestia kuhniella) in 1915 [1]. The first record of its application to control insects was in Hungary at the end of 1920, and in Yugoslavia at the beginning of 1930s, it was applied to control the European corn borer [2]. Bt, the leading biorational pesticide was initially characterized as an insect pathogen, and its insecticidal activity was ascribed largely or completely to the parasporal crystals.…”

Relationship between chemical properties of the soil and the occurrence of Bacillus thuringiensis

“…These inclusions are toxic to a wide variety of insects and many of them are commercially used against insect pests of Lepidoptera, Diptera and Coleoptera orders. Bt based biopesticides are the most successful ones and they represent approximately 80-90% of biological pest control agents worldwide (GLARE & O´CALLAGHAM, 2000;HABIB & ANDRADE, 1998 (LORD, 2005).…”