[1] At the early stage of Asian Soybean Rust, it causes yellow mosaic discoloration on the upper surfaces of older foliage.

Mature tan lesions consist of small pustules surrounded by discolored necrotic areas.

Besides, ASR pustules are raised and can be commonly found on the underside of the leaf which makes it different from the lesions caused by spot diseases.

For example, Australia, China, Korea, India, Japan, Nepal, Taiwan, Thailand, the Philippines, Mozambique, Nigeria, Rwanda, Uganda, Zimbabwe, South Africa, Brazil, Argentina, and Paraguay.

A continuous period of wetness on leaves will aid the growth of this disease since this situation is required for spores to germinate.

However, this pathogen can be spread easily from wind and storm fronts and can inoculate quickly within a soybean field under favorable environmental conditions.

[2] And the Asian Soybean Rust may be favored by the climatic anomalies phenomena that cause extreme rainfall natural disasters that is called El Niño.

[13] Soybean rust is spread by windblown spores and has caused significant crop losses in many soybean-growing regions of the world.

It is likely that ASR will survive on vast acreages of naturalized kudzu in the southern U.S. and thereby establish a permanent presence in the continental U.S.

[15] Additional hosts can serve as overwintering reservoirs for the pathogen and allow for build-up of inoculum, in those environs free from freezing temperatures.

The pathogen is well adapted for long-distance dispersal, because spores can be readily carried long distances by the wind to new, rust-free regions.

[16] Spores of the soybean rust pathogen are transported readily by air currents and can be carried hundreds of miles in a few days.

Rust spores, called urediniospores, are able to penetrate the plant cells directly, rather than through natural openings or through wounds in the leaf tissue.

Abundant spore production occurs during wet leaf periods (in the form of rain or dew) of at least 8 hours and moderate temperatures of 60 to 80 °F (16 to 27 °C).

[16] The infection process starts when urediniospores germinate to produce a single germ tube that grows across the leaf surface, until an appressorium forms.

When appressoria form over stomata, the hyphae penetrate one of the guard cells rather than entering the leaf through the stomatal opening.

The direct penetration of the epidermal cells and the non-specific induction of appressoria in the infection process of P. pachyrhizi may aid in understanding the broad host range of the pathogen and may have consequences in the development of resistant cultivars.

If conditions for re-infection are sporadic throughout the season, significant inoculum potential still remains from the initial infection to reestablish an epidemic.

[citation needed] Rust-resistant varieties of soybeans are currently in development by both public universities and private industry.

[18][19] In some regions, the selection of winter cover crops and forage legumes may be effected, since they can serve as host plants.