eChapter Name: Compatibility between Microbial Pesticides with Synthetic Pesticides
9789390083343
eBook Name: PEST MANAGEMENT AND RESIDUAL ANALYSIS IN HORTICULTURAL CROPS
by Monika Geroh, H.D. Kaushik, P. Bhatnagar, Asha
The food plants of world are damaged by more than 10,000 species of insects, 30,000 species of weeds, 1,00,000 diseases (caused by fungi, bacteria, viruses and other microorganisms and 1000 species of nematodes (Hall, 1995). The global losses due to various categories of pests vary with the crop, geographic location and weather. Total yield losses from different pests to all the crops have been estimated to be US$ 500 billion worldwide (Oerke et al., 1994). In India, the current losses due to insect pests in principal field crops have been estimated to be Rs. 6, 89,400 million (Dhaliwal et al., 2004). In addition, there is loss of Rs. 60,000 million due to insect pests during storage. Thus, total losses to major crops and food grains in storage caused by insect pests are estimated to be Rs. 750 billion annually (Dhaliwal and Arora, 2006). Among regions, losses in Asia and Africa almost reaches 50 percent whereas in Europe (28.2%), North America (31.2%) and Oceania (36.2%) are below average. Losses due to animal pests in Asia (18.7%) are almost double those in developed countries and losses from weed competition in Africa and Asia are approximately double than those in Europe (Oerke et al., 1994). To combat such heavy losses mostly chemical pesticides are used by the farmers but indiscriminate use of pesticides has led to severe ecological consequences like destruction of natural enemy fauna, effect on non target organisms, residues in consumable products including packed pure and mineral water and ultimately resistance to the pesticides, to which we solely rely. Insecticides are always required to suppress rapidly expanding insect pest populations. Strategies should be employed to increase efficiency and accelerate insect mortality by combining microbials with sub lethal doses of chemical insecticides and botanicals. Biointensive pest management (BIPM) is the recent trend in Indian farming and attracting the farmers for higher income to their produce. This has resulted due to increased awareness among the end users and concerns about the deteriorating ecological situations among the eco-campaigners.
Microbial pesticides consist of disease causing microorganisms, which are disseminated in the pest populations in large quantities in a manner similar to application of chemical pesticides. It includes bacteria, viruses, fungi, nematodes and some protozoans. Pathogens may exert controlling effect by means of their invasive properties, toxins, enzymes and other substances (Lewis, 2006). The use of microbial insecticide has been proved to be a viable alternative to chemical insecticides, especially in management of forest insect pests. The combination of particular active ingredients and their ability of replication in host populations in the fields define the major differences between microbial insecticides and chemical insecticides. These differences have practical implications for their use in insect pest management programmes.