Their work will reduce losses, save remedial treatment costs, and more effectively protect quality. Civilisation was founded on the ability to harvest, store and distribute grain and it will continue to flourish only as long as we maintain effective supply of these foods. Grain is harvested at specific times during the year and must be stored so food is available throughout the year.
A major natural threat to the safe storage of grains is its spoilage and destruction by insect pests. This threat is greatest in warmer climates, shared by India and Australia, because insect population growth is favoured, resulting in very high infestation pressure and the potential for significant losses.
In India, post-harvest losses of food grains from all causes average 11-15% of total production, or about 20 million tonnes, equal to about half of all the grain produced in Australia annually. These losses amount to more than Rs. 50,000 crore (>A$10 Billion) per year.
Insect infestations alone are estimated to reduce production by 3-15% depending on climate, commodity and storage structure. Postharvest losses would be enough to feed about 70-100 million people, or about 1/3rd of India’s poor and equate to the production capacity of more than 11 million hectares of arable land.
The threat of insect infestation is also significant in Australia, but direct damage although still important, is not the major issue because Australia already has a well-organised grain handling network. The central concern here is the ability to meet both international and domestic market demand for an insect-free product. Unlike other advanced grain producing countries, the Australian harvest occurs at the beginning of summer, so the crop is stored over the hottest part of the year, placing it at risk of insect infestation for much longer periods than its competitors. To supply local needs and provide a reliable food supply to international customers, the Australian grain industry must be able to manage the constant pressure of insect infestation effectively.
Depending on resources available, grain supply chain managers implement an integrated approach to controlling insect pests using several tactics, such as cooling or drying the stored grain as well as removal of stray grain from the storage site. Grain temperature and moisture are the most important environmental determinants of insect population growth so that by lowering them reduces insect numbers. However, the required specialised infrastructure does not exist at most storage facilities even in developed countries. Moreover, the insect challenge in warm climates is such that these techniques are not sufficient to maintain grain security over the long storage periods required. In both developed and developing countries, storage managers are forced to use chemical treatments, such as fumigants, to disinfest grain and, sometimes, less desirable residual insecticides to protect grain.
Health, safety, environmental and economic considerations severely limit the range of chemicals that can be applied to grain, and authorities worldwide have steadily reduced the number of chemicals available. Chemicals that can be applied to grain are, in any case, rare and costly to develop.