Management of Insect Pests by Microorganisms

Abstract

Insects, like other organisms, are susceptible to a variety of diseases caused by bacteria, viruses, fungi and protozoans, and these pathogens are exploited for biological control of insect pests through introductory or inundative applications. Microbial pathogens of insects are intensively investigated to develop environmental friendly pest management strategies in agriculture and forestry. In this paper, the scope for utilization of insect pathogens in pest management in the world and India is reviewed. The most successfully utilized insect pathogen is the bacterium, Bacillus thuringiensis (Bt) which is used extensively for management of certain lepidopteran pests. In India, mostly imported products of Bt kurstaki have been used, which are expensive and there is an urgent need to develop aggressive indigenous Bt strains against various pests. Baculoviruses comprising nuclear polyhedrosis virus (NPV) and granulosis virus (GV) have been successfully used as insect pathogens because of their high virulence and specificity. NPV and GV formulations are used for lepidopteran pests like Helicoverpa armigera (HaNPV) and Spodoptera litura (SlNPV) in India, besides Anticarsia gemmatalis NPV in Brazil, Lymanttria disper NPV, Orgyia pseudotsugata NPV in USA and GV of Pieris rapae in China. Lack of easy mass multiplication methods for the commercial production of baculoviruses calls for R&D to develop production in insect tissue cultures. Entomopathogenic fungi like Beauveria bassiana, B. brongniartii, Metarhizium anisopliae, M. anisopliae var. acridium, Lecanicillium spp., Hirsutella thompsonii, Nomuraea rileyi and Isaria fumosorosea are gaining importance in the crop pest control in recent years due to the simpler, easier and cheaper mass production techniques. Environmental humidity and temperature play an important role in the infection and sporulation of these fungi and as such they are highly suitable during cool and humid cropping seasons. Successful uses include M. anisopliae var. acridium for locust control in Africa, Australia and China, M. anisopliae in sugarcane spittle bug management in Brazil and pine moth (Dendrolimus spp.) control in China using B. bassiana. Since talc -based formulations of these fungi have limited shelf life of 3-4 months, alternative formulations with longer shelf life (12-18 months) have to be developed besides suitable oil based formulations for dry land agriculture. There is a scope to utilize the biodiversity of Entomophthorale group of fungi like Entomophthora, Zoophthora, Neozygites etc., which have potential for management of aphids, thrips and lepidopteran pests.

NEW RECORD OF ENTOMOPATHOGENIC BACTERIA, Bacillus aryabhattai STRAIN B8W 22, ISOLATED FROM Cassida vittata Vill. AND ITS PATHOGENICITY AGAINST THIS INSECT IN EGYPTIAN SUGAR BEET FIELDS

“…Also, El-Husseini (2006) showed that the entomopathogenic bacteria an important factor of the natural mortality to insect pests. Ramanujam et al (2014) reported that the main advantages of these biocontrol agents are their specificity to target pests, safety to the nontarget organism. They do not cause ill effects on environment and human health and can be used against pests which develop resistance to the conventional insecticides.…”

A New Frontier for Biological Control against Plant Pathogenic Nematodes and Insect Pests I: By Microbes

“…The broken line inset box indicates the common microbial determinants of both insecticidal and nematicide capacity. Duarte et al, 2016;Gonzalez et al, 2016;Khan et al, 2016;Malekan et al, 2015;Mascarin and Jaronski, 2016;QuesadaMoraga et al, 2006;Ramanujam et al, 2014;Safavi, 2013;Xu et al, 2009 Metarhizium anisopliae Haase et al, 2015;Monteiro et al, 2012;Ramanujam et al, 2014;Yang et al, 2012HezeSNPV Helicoverpa zea Gemstar, HzNPV CCAB Haase et al, 2015Lacey et al, 2015;Rowley et al, 2011 MabrNPV Mamestra brassicae;H. armigera;S.…”

Productivity, pathogenicity, host range, and spore mass-propagation of local strain of Mattesia sp. isolated from insect cadavers of certain stored grain pests in Egypt

“…Hence, controlling stored product insect pests may be most beneficial in long-term storage since such entomopathogenic protozoans produce slow-acting chronic infection. Furthermore, they may cause a reduction in host vitality, feeding, fecundity, longevity, and survivorship (McLaughlin, 1971;Khan and Selman, 1989;Flinn and Schöller, 2012;Ramanujam et al, 2014). Weiser et al (1976) recorded promising examples for certain entomopathogenic protozoans that cause reductions in storage insect pests.…”