Soybean rust Soybean rust Soybean rust is a disease that affects soybeans and other legumes. It is caused by two types of fungi, "Phakopsora pachyrhizi", commonly known as Asian soybean rust and "Phakopsora meibomiae", commonly known as New World soybean rust. "P. meibomiae" is the weaker pathogen of the two and generally does not cause widespread problems. The disease has been reported across Asia, Australia, Africa, South America and the United States. Soybean is one of the most important commercial crops around the world and in the United States. Asian soybean rust is the major disease that affects soybeans. It causes lesions
Soybean rust kidney beans, peas, leguminous forage crops such as trefoil and sweet clover and weeds such as kudzu. At the early stage of Asian Soybean Rust, it causes yellow mosaic discoloration on the upper surfaces of older foliage. At this stage, it is usually hard to identify since the symptoms are relatively small and poorly defined. Later as the disease continues to progress, the leaves will turn yellow and there will be lesions mostly on the undersides of the leaves and sometimes on petioles, stems or pods and premature defoliation can also be observed. Asian Soybean Rust produces two types of