What is the disease of coffee planting that harms coffee leaf rust?

Coffee leaf rust was discovered in Central America as early as 40 years ago, but recent outbreaks in Central America (Colombia, Costa Rica, El Salvador, Guatemala, Nicaragua) and Mexico are by far the most serious. Guatemala, Honduras, Costa Rica and other countries have declared a national state of emergency.

The president of Guatemala says leaf rust will reduce coffee production in Guatemala by 40% in the 2013-14 season. Guatemala accounts for 14% of global coffee raw bean production, so a rise in coffee prices will be inevitable.

In the past 20 to 25 years, there has been a strong global demand for raw coffee beans. In order to increase production, many coffee farmers in Central America have abandoned the traditional shade planting technique and adopted the "sun exposure" method to grow coffee. Due to the loss of the protective effect of "tree crown" and the reduction of biodiversity, the control of diseases and insect pests can only rely more on the use of pesticides and fungicides, which not only destroys the original complex ecological network, but also leads to the reduction or even disappearance of white halo fungus, which can control insects and caffeine leaf rust, resulting in a large-scale outbreak of leaf rust.

What is more serious is that the deterioration of the ecological environment and ecosystem may lead to more complex problems.

The unanswered question is: is this large-scale outbreak of leaf rust the first appearance of a single event or a new normal event?

Leaf rust is the most serious coffee disease. It first appeared in Lake Victoria in East Africa in 1861 and ravaged Sri Lanka in 1867, resulting in the destruction of the Sri Lankan coffee industry. It soon spread to many parts of Southeast Asia and eventually spread to the entire southern, central and western African coffee producing regions.

Before 1970, leaf rust had not been found in the Western Hemisphere until the outbreak of leaf rust in Bathia, Brazil, in 1970. since then, leaf rust has been found in all coffee producing areas in the world.

Leaf rust is mainly caused by the infection of coffee leaves, buds and new coffee fruits, which leads to the death of coffee trees; coffee rust spores spread the lesions on the lower side of the leaves through the wind and Rain Water.