ENTOMOPATHOGENIC FUNGI, AN ECOFRIENDLY APPROACH TO COPE INSECT PEST.
Novel tactics in field of applied Entomology have reformed the ways for the management of notorious insect pests. Agriculture, being a mainstay of economy, contributes 23% in Gross Domestic product (GDP) and engaging approximately 45% of employed labor force. Instead of its undeniable significance unfortunately, Pakistan has made no significant development in this field, due to economic and some policy constraints.
As for as plant protection measurements are concerned, Integrated Pest Management (IPM) is an effective and environmentally sensitive approach in pest management program that relies on a combination of common-sense practice. IPM programs use current and comprehensive information on the life cycles of pests and their interaction with the environment. This information, in combination with available pest control tactics, is used to manage pest infestation by the most economical means, and with the least possible hazard to people, property, and the environment.
The IPM approach can be applied to both agricultural and human health welfare. Insect pest are the key factor among all other biotic factors that are responsible for low crop yield. The damage caused by insect pests may vary from 30 to 50% in major cash crops of the country. To combat these pests, our farmer community allegedly relies only upon the use of pesticides without bothering repercussions. It is estimated that farmers use US$ 300 million worth of pesticides annually, of which more than 85% insecticides applied in the field never reach to the target organism but disperse through air, water and soil. Moreover the injudicious use of board spectrum insecticide and their impact on ecological system was brought to serious criticism in 1962 with the publication of silent spring by Rachel Carson. As the matter of fact, the massive use of insecticides has raised serious problems of environmental contamination, presence of residual effects in food commodities, mortality of non-target organisms, resistance and resurgence of insect pest populations. Now, Food and Agriculture Organization of the United Nations has recommended the “Ecosystem Approach” in agricultural management, including IPM, combining different management approaches to cultivate high quality crops and mitigate pesticide use.
It is therefore, essential to develop such control methods, which should be environmentally safe and nondestructive to biodiversity. An alternative to chemical control is biological control, the use of natural enemies to control pest species including microbial control with entomopathogens, predators and parasitoids.
Among all naturally occurring bio-control agents Entomopathogenic fungi (EPN) like Beauveria bassiana and Metarhizium anisoplae are found to be promising alternative to the use of hazardous synthetic insecticides because of its host specificity, efficacy and ecofriendly behavior. EPF also have noteworthy advantage over other microbial agents in IPM as it can be used to kill all the developmental stages of insects.
Today there is a worldwide considerable interest in using the EPN against different pests. The bio efficacy of EPN is based upon its peculiar mode of action. The entire process of EPN accomplished with in insect body consists of 5-6 steps viz. 1) attachment of fungal conidia with insect cuticle; 2) spore germination; 3) penetration of insect cuticle; 4) overwhelming the immune response of insects; 5) multiplication of hyphal cells; 6) sporulation from cadavers. Due to its astonishing efficacy against pest, the chances of resistance development are very low.
In spite of several advantages of EPF But still in Pakistan these conventional and harmful pesticides are applied in field at large scale, thereby perturbing environment and polluting our food commodities. Now it’s time to motivate and literate our farmer community towards Precision Agriculture that lies in the secret of Integrated Pest Management.
Muhammad Zaeem Mehdi, Zeshan Khaliq, Abdul Rehman and Muhammad Bilal Hussain.
Address : University of Agriculture Faisalabad.