Soybean Rust


Soybean Rust

Phakopsora pachyrhizi


In a Nutshell

    Small, grey spots on the underside of leaves and along the veinsGrey spots turn reddish to brownYellow discoloration of the surrounding of the spotsSymptoms can be found on all leaves in late stage of infection

Hosts: %1$s

· Soybean


Infection starts in lower parts of the plant and then moves upwards. First symptoms appear around flowering stage in the form of small, grey spots on the underside of leaves and along the veins. Later, these spots increase in size and number, coalesce and turn reddish brown or black, often surrounded by a yellowish halo. They are now present on both sides of the leaf, the petioles, and sometimes the stems. As the disease progresses, they become covered by raised, pale-brown fungal pustules visible to the naked eye.


Soybean rust is an aggressive disease caused by the fungus Phakopsora pachyrhizi. It needs mild winters and alternative hosts to survive when there are no soybean plants around because it can't live and reproduce without green living tissue. Rust spores can penetrate the plant cells directly, rather than through pores or wounds in the leaf tissue. The development of the disease is favoured by 6 to 12 hours of continuous leaf wetness, moderate temperature (15 to 25°C) and high humidity (>75%).

Biological Control

Apply products containing essential oils of Corymbia citriodoria at 1 %, Cymbopogon nardus at 0,5%, and Thymus vulgaris at 0,3 % to reduce the severity of the infection.

Chemical Control

Always consider an integrated approach with preventive measures together with biological treatment if available. Selecting the right fungicide and applying it at the right time is crucial. Apply fungicides of the chloronitriles, strobilurins, and triazoles groups. Apply formulations of zinc ion-maneb complex periodically throughout the growing season.

Preventive Measures

    Select tolerant or resistant varietiesPlant early and if possible choose an early maturing cultivarAlternatively, plant late to take advantage of drier periodsUse wider row spacing to hasten canopy dryingMonitor your plants regularly and weed out alternative hostsAdjust soil fertility, particularly potassium and phosphorus levels


Regional Weather

Get detailed forecast and actual weather data.

Plantix offers detailed weather information on the following issues:



Air Pressure


Wind speed

Plantix Community

Get in touch with experts around the world.

Post your questions

You can post your questions and pictures and get feedback from other farmers or gardeners. Plantix' experts will answer your questions related to plant diseases and pests.


Exchange with Plantix users around you, in your language and related to the crops you grow.

Global Community

Connect to farmers, gardeners, experts and interested people around the world that discuss plant diseases, remedies and best practice for sustainable farming.

AI-Driven Disease Detection

Instant diagnostics and solutions based on your picture

Image Recognition

Plantix analyzes your picture within a few seconds and gives you instant feedback on your plant problem.

Customized Management Options

On top of the detection result, Plantix offers you a detailed description of possible solutions - both biological and conventional.

Preventive measures

Plantix offers information on preventive measures to protect your crop from the next attack.