How to Prevent Storage Pests and Post-Harvest Loss of Food Grains

At the time of harvesting of the crops, if we can procure it, we can get it for a fair price. If we buy it during the off-season, we may have to pay more. This is due to two things. First is that the storage is a costly affair. Second thing is that during the off-season there is more demand. So, the demand-based price is always high.

One of the important thing during storage of grains is to protect it from moisture content. If there is more moisture, food grains usually rich in carbohydrates will ferment or get infested with microbes like fungi. organisms which are involved in degrading the stored food grains are known as storage food pests.

In India alone, due to storage loss, about 10 per cent of the food grains getting useless. It is around 14 million tonnes of food grain of about 70 million INR of value.

We are having different types of pests attacking food grains. These are ranging from organisms like the rodents, insects and fungi.

Among the various pests, important threats to food grain storage are the different types of insects. Insects hatch, breed and destroy enormous quantities of food grains every year.

The rodents, mainly rats also feed and destroy lots of food grains. This is not only feeding and destroying the grains but also making the environment very unhygienic. Due to such pest attacks, most of the facilities get destroyed and food grains become useless. This way food grain storage facilities are having a lot of loss due to pests.

The pests arrive either through flying or entering into the storage area through air, moisture or surface. If the entry is blocked, our effort would be successful. Sometimes, the spores or eggs previously came into contact with the storage materials get life in due course of time and become a problem. So, store it pure and quick in airtight containers or bags.

Cleaning the grains and putting under the sun is the easiest method of disinfestation and it is the safest one also. After sufficiently drying they are put in airtight containers. Then chances of pest attacks are low. Quality of the food grains also one of the reasons for attracting pests. Sweeter carbohydrates, essential oil content, rich proteins, are all some of the reasons sent and good quality which are attracting the pests on to it.

Double layered and triple-layered plastic bags are effective to certain extent. Purdue University has introduced novel plastic bags to prevent pests. If these are stored inside wooden compartments, then chances of pest attack is very negligible. However, over the years due to weathering and wear and tear, pest entry becomes easy.

A number of chemicals and natural products such as oils are used to control the pest buildup in stored food grains.

Over the years these facilities give way to the pests unknowingly. Periodic check-ups and disinfecting activities are important to retain the grains pest-free.

Natural products against pests

There are a number of traditional knowledge-based methods and natural remedies for eradicating the pest from food grains. Here are some traditional and modern methods for storage.

• Turmeric powder and garlic are mixed with rice before packing in polythene bags.
• Castor oil is used as one of the resistant oil coatings on rice. This acts as a protective coating over the rice grains which repels the pests.
• Plant leaves with insect repellent properties such as Neem, Vitex negundo, Glycosmis pentaphylla, Acorus calamus, Murraya koenigii, etc. are also mixed with rice and used as repellants with minimal effect.
• Neem leaves and dried red chillies are mixed with rice before packing in polythene bags.
• Instead of polythene bags, airtight polystyrene containers are also used.
• Mercury based Paarad tablets are tied in the muslin cloth and put in between rice grains.
• Fumigants are used to either put in a container or in the storeroom. These either kill or deter the pests from the food grains.
• If the grains are stored in large open godowns, then heaps of the grain are properly covered and then over that contact insecticides are sprayed.
• Sealing of godowns helps in preventing rodents.
• Traps can be used to prevent insects by pheromones and rodents by cages or rat traps.

Use of any one of the above safe methods which have to be chosen according to the environment.

Synthetic pesticides

Pesticides such as chlorpyrifos, neo-nicotinoids, synthetic pyrethroids are very dangerous. Same is the case with fumigants such as aluminium phosphide against insects or bromadiolone against rats which put the consumers at risk.

Health issues are the most important ones as far as we are controlling pests in the rice grains by using various pesticide products. Those who have the grains food either in raw form or in cooked form should not have any health issues. Usually, natural products after washing will not cause harmful effects. Prevention of post-harvest losses of food materials will save food materials and eliminate hunger from the world.