Grain stored pest predators

Use of predators is one of many conventional biological techniques for stored –grain pest control. Others are including, use of parasites, insect disease and sterile males, the use of pheromones for pest monitoring, mating disruption or enhanced mass trapping, and the use for resistant crop varieties.

Many storage pests will prey on other insects present including members of their own species. Obligate predators only feed on other insects.

Lyctocoris campestris is a worldwide generalist predator of stored product insects that produces best growth and reproductive responses when exposes to grain moths instead of to common stored product infesting beetles.

Xylocoris flavipes, a cosmopolitan species called the warehouse pirate bug, is commonly found associated with stored product insect pests and studies showed they inhibited population buildup of four species of beetles that attack stored grain.

Some interesting biological characteristics of the warehouse pirate bug are that it requires a low number of prey to complete its development and uses cannibalism to survive when prey are absent.
Grain stored pest predators

Commercial storage of grain

Proper and safe storage of grain is necessary to ensure their availability throughout the year.

The principle systems used are the silo (elevator), the flat bin (warehouse) and the bag store. The last is sill common, although declining in developing countries.

The type of structure to be chosen for storage will vary according to region, volume, variety of grain, method of handling ie. bulk or bag, cleaning, drying, grading, treatment, power supply, available construction materials, period of storage and financial resources.

A silo is a tall, self contained, usually sealed cylinder. After a harvest, farmers use silos to store grains until they go to market.

The high silos are circular, which gives maximum strength for minimum materials used and makes them easier to keep clean. Across the heartland of America, grain silos are a common sight. On the flat prairies, they are conspicuous.

Silos of up to 10,000 tones are constructed of either steel or concrete. Grain silos have mass customization and inventory management capacities, and computerized stored grain management system.

In modern stores grain handling is usually fully mechanized and is often controlled from a central control panel with a wall-mounted mimic display or computer representation of the store.

In computerized units the location and amounts of stock can be recorded in the computer.

Silos have well defined functions: they store grain and dispense it at the appropriate time.
Commercial storage of grain

Grain physical properties important to storage and transport

The cereals are traded internationally as whole grains or as final rather than intermediate products. These include pasta foods and high value products containing cereals.

Therefore it is important the physical properties of cereals in order to predict grain pressure packing behavior and flow behavior include bulk density of the grain, the ratio of lateral to vertical pressure, the internal angle of friction and the coefficient of friction of grain on the bin wall.

For successful storage it is important to avoid excessive temperature, high moisture, predation by insects and other invertebrates. The important points of cereals properties for storage include:
*The soft floury endosperm. This favored by weevils as being a more easily eaten food that the vitreous endosperm. Hard vitreous grains are more denser and more difficult for insect to penetrate.

*The embryo. If this has been damaged at threshing or during handling, the inherent enzymes will break down the fat, leading to off-flavors in foods made from the grains.

*Size and shape of the grains. Small grains less than around 12 g per 1000 grains are not attacked by weevils.

Insect infestation deteriorated grain quality, Nutritional value in terms of thiamin content decreased in infested wheat together with changes in physiochemical properties including weight, density, increased uric acid and fat acidity increased moisture content and changes in crude fat, calorific value, true proteins, ash, crude proteins, crude fiber and non- protein.

The physical properties vary in the same way as the composition. In addition, harvesting, handling, storage and abuses during movement of grain from storage cause significant changes.

Storage can be for varying lengths of time, ranging from short term storage on farm for drying and waiting for advantages market iodations to long term storage for strategic reserves.

Grain ages during storage and changes it properties significantly, which means that processing properties change.
Grain physical properties important to storage and transport

Grain storage during ancient Egypt

Storage is the intermediate stage between cereal production and processing and its distribution and consumption.

By ancient Egypt times grain storage and progress from the simple family store to large state-run systems.

The dry climate of Egypt would have indeed allowed farmers to bulk process their harvest communally to the clean grain stage prior storage.

Even without the sophisticated equipment that is available today, grain storage proved remarkably non-problematical in ancient Egypt, although infestation was always a potential problem.

Some of these have been excavated: they were made of dried clay bricks or baked bricks and had domed roofs.

It was the system that was almost certainly used by Joseph, he gathered in the grain of the seven good years before the seven famine years and thus with careful rationing, prevented starvation.

At that time the system was highly organized, hierarchal system of grain storage, which for the most part was successful in feeding population, even during the lean years.

Grain was stored at national, regional, local and household levels.

The state would have to collect and manage surpluses and meet local as well as central needs in case of any difficulty.

Archeological evidence indicates that large storage facilities were attached to temples and palaces.
Grain storage during ancient Egypt

Pest Type: Commodity feeders

Insects infesting stored grain feed and live in a number of ways, including:
*Commodity feeders
*Fungal feeders
*Predators
*Parasitoids
*Scavengers

Commodity feeders feed directly on commodities and can be conveniently divided into primary pests- those that attack intact commodities and secondary pests, which require the commodity to be damaged before they can attack it.

In reality, each pest requires a different level of damage before it can survive on a commodity.

For some species this level is minimal, but for others it may be substantial.

Commodities accumulate damage from harvesting, handling, pest attack and processing, which increases the risk of attack from secondary pests.

Secondary pests dominate in milled products such a flour, and processed and manufactured food products.
Pest Type: Commodity feeders

Storage Grain

Storage Grain
For most purposes, pests and procedures are the same for all cereals and other dry commodities.

Cereals spend more time in transport and storage than in processing or the kitchen: in communities in which only one harvest a years is possible, the grain may be stored for as long as 6 months, with consumption removing only the half.

During that period and onward to the next harvest, the grain must be protected from partial or total loss. In a typical year the ration of world grain stocks to consumption will average 22%.

Food and food stuff have been stored ever since primeval humans first kept some over from one day to the next and the basic problem has not change: how to retain a wholesome stock with no loss of quality or quantity.

The causes of loss are also the same: other creatures also with to use the food, be they vertebrate (birds, rodents), invertebrate (insects, mites) or microorganisms (mold).

The primitive family store is still in use in more backward societies: grain is dried in the sun and stored either in a hole in the ground or a simple container.

In very arid climates where the soil is for, the hole is in fact, a reasonable system.

Containers are made from gourds (the shell of a local pumpkin); from clay, either raw or fired; or most commonly, from wickerwork (grain baskets).

The advantages of this is that the same materials and design can be used for a wide range of quantities from very little to several tones.

The basketry may be sealed with clay to prevent entry of insects and small rodents. Termite clay is particularly effective for this.
Storage Grain

Storage of grain: Factors to be considered

Storage of grain: Factors to be considered
Storage facilities vary from small inexpensive steel or wooden bins on the farm, to elaborate incorporating mechanized ventilation.

On the farms, the circular type of steel bin holding approximately 1,000 bushels of grain is popular, while for terminal storage, a single elevator often has a capacity of several million bushels.

Virtually all of large storage and central market elevators, as well as many country elevators, are built of reinforced concrete so as to attain many years of usefulness and to reduce the fire hazard.

Marketing wheat commercially depends upon the concept that, when reasonable dry, the grain can be stored for long periods without undergoing a change in grade.

Deterioration of wheat in storage with a consequent lowering of grade can have serious economic consequences for the elevator operator.

Wheat is a biological material which is alive and it can deteriorate and die in storage of either the moisture content or temperature becomes too high.

Wheat is also subject to attack by microorganisms, insects and rodent when storage conditions are inadequate. For safe storage the following must be considered

*Moisture content
*Temperature of the wheat
*Infestation
*Type of bin

Storage deterioration can be controlled by drying damp wheat to safe moisture content and keeping it dry and cool, by providing good storage structure, and by aeration or forced ventilation.

Fumigation or chemical protectants will control infestation.

There is ample evidence that, under optimal conditions, wheat does not deteriorate with storage space age, at least for several years.

It appears that the length of storage of wheat within reasonable limits, has no appreciable influence on the storage properties of the flour milled from the wheat.

When wheat is stored improperly, deterioration is possible from many causes including:

*Insect damage
*Molds
*Heat damage
*Damage to the germ
*Sprouting
*Rotting
*Damage by rodents

These factors not only injure wheat and cause economic loss by lowering its value for milling or other end uses, but they can also cause actual loss in weight of the wheat, bring about undesirable changes in odor, sanitary quality, and nutritive value, and can alter important properties of starch, lipids and protein.
Storage of grain: Factors to be considered