Biological Control of Insects: A Sustainable Approach
Asim Munawar1*, Aqsa Arshad1, Naeem Ahmed2, Muhammad Waseem Shoukat3 , Shehbaz Sharif 1,
Waleed Afzal Naveed1
1 Department of Entomology, University of Agriculture Faisalabad
2 Department of Agronomy, University of Agriculture, Faisalabad
3 Department of Plant Pathology, Bahauddin Zakariya University,Multan
Corresponding Author Email: [email protected]
Insects are one of the most important creatures on earth. The term biological control was first used by Smith in 1919 to signify the use of natural enemies to control insect pest. Biological control in an ecological sense can be defined as the regulation of natural enemies of harmful insects at high density than the normal lower density. This definition of natural control does attempt to prescribe the population densities involved only that could be lower than would be true if the responsible factors were withdrawn or made ineffective. Thus, this definition does not cover degree of biological control in the economic sense, which must be separated in relation to any particular pest organism.
Biological control is the use of parasitoid predators or pathogens to attack an insect and reduce its number. It has the same fundamental objective as any other control measures avoiding or minimizing economic loss. Parasitoids and predators cannot prevent all damage by pest since their relationship with the pest tends to evolve the point where both survive and the host is not reduced to zero. Pest status is reducing by increasing pest mortality, frequently by increasing existing natural enemy to prey ratios by biological control methods. Attempts at increasing ratios include placing natural enemies in the environment and modifying the environment to increase natural enemy numbers.
Another method use to raise ratios in modifying established crops production practices so that natural enemies otherwise destroyed are conserved. Not all pests are equally suited for control by introduced natural enemies. The cause of each problem must be assessed. Native insect and weed pests often have existing compliments of natural enemies which are rendered ineffective due to cultural practices or other reasons. Whether pest problems of this nature can be solved by introducing additional natural enemies is often unclear and in many instances unlikely. On the other hand, the probabilities are generally good for controlling introduced pests by introducing their parasitoids and predators fore country of origin.
Thus the amenability of a particular pest to biological control is neither clear cut nor always predictable. The degree of success achieved through biological control is in direct proportion to magnitude of the research efforts expended. Success frequently becomes a question of resource limitations.
Biological Control in Pakistan: Work on biological control was started in 1956. When common wealth institute of biological control (CIBC) was established with Dr. M.A. Ghani as its first in charge, work was started on various projects of special interests.
Methods of Using Biological Control Agents: Biological control agents can be purchased from commercial suppliers and released for supplementary control of pests. However, most biological control occurs without assistance from people. Many predators, parasites and pathogens occur naturally and are continually working to help keep nature in balance. The importance of natural enemies is often not appreciated until a broad spectrum pesticide, which kills many beneficial as well as the targeted pest, is applied and a new pest suddenly released from biological control becomes a serious problem. Conservation and enhancement of natural enemies already present in the system can be a very effective method of biological control.
Conclusion: Farmers can reduce their dependency on chemical pesticides by using biological control agents as an alternative, due to their similar inhibitory properties. Biological control is an environmentally sound and effective means of reducing or mitigating pests and pest effects through the use of natural enemies. The aim of Biological Control is to promote this science and technology through publication of original research articles and reviews of research and theory. The journal devotes a section to reports on biotechnologies dealing with the elucidation and use of genes or gene products for the enhancement of biological control agents.