What are the factors that can enhance insect infestation in stored grain?

Stored grain in storage structures were spoiled due to attack of different insects-pests, fungi, rats, mice, squirrel, birds etc. In storage, a number of biotic and abiotic factors and their interactions are responsible for insect multiplication and subsequent grain damage.

The occurrence and development of an insect infestation is dependent on many factors such as source of insects, available food, temperature, moisture, air, condition of the feed-stuff, presence of other organisms, and the efforts to exclude or kill the pests.

Major factors responsible for enhancement of insect damage are: temperature, relative humidity, and moisture content of the feed ingredient.

Temperature is the most important environmental factor affecting insect development and reproduction. Most insects do not reproduce at temperatures lower than 12 °C or higher than 34 °C. The optimum temperature for reproduction is about 26 °C.

The nutritive content and certain physical properties of feeds will also determine the vulnerability of such materials to attack. Only a few insect species are able to attack sound kernels of feed grains.

Different insects and spoiled grain provide suitable conditions for growth of fungi and further spoiled the grain. Primary pest that cause most grain damage are the granary, rice and maize weevils; the lesser grain borer; and the Angoumois grain moth.

High moisture content (16 percent or more) renders feed grains soft and susceptible to attack. High grain moisture content due to prevailing high atmospheric humidity generally above the safe moisture levels (14% for paddy, 13% for milled rice, 12% for wheat, 1% for oilseeds and 9% for pulses). Meals pressed into cakes or hard flakes are more resistant. Insects appear to eat small particles more readily than large ones.
What are the factors that can enhance insect infestation in stored grain?

Coffea Canephora

Coffea Canephora
Coffea canephora, which produces the popular robusta beans, is the second most important variety of the coffee plant.

Like its arabica cousin, C. canephora can grow tall; if left to its own device, it can attain a majestic thirty feet in height.

But like the Arabica plant, it is kept to about eight feet in height to allow for harvesting.

In other ways, too, the robusta plant resembles the arabica plant.

C. canephora doesn’t deliver a crop until three to five years after it is planted, after which the fruits take almost a year to mature. And the plant can continue to bear cherries for twenty to thirty years.

Like C. arabica and C. canephora appreciates sixty inches of rain per year. However, this plant likes it considerably hotter than its arabica cousin, and also tolerates higher humidity.

Grown mainly in West and Central Africa, Southeast Asia and parts of South America, robusta plants do best in equatorial conditions with temperatures ranging from the mid- seventies to the mid eighties, and altitudes ranging from sea level to 3,000 feet.

They also differ in that they are both more resistant to disease and higher yielding than robusta plants. The typical robusta tree yields as much as two to three pounds of beans per year – about twice the amount produced by an arabica plant.

Moreover, at 2 percent caffeine by weight, the caffeine content of robusta coffee is higher than that of arabica.

Robusta beans are considered inferior to arabica because they are far less flavorful, with a distinct bitterness.

This is why robusta beans are less expensive than arabica beans and are often used in lower grade commercial coffee blends, as well as in the processing of many instant coffees, both flavored and unflavored.
Coffea Canephora