Lupine anthracnose

Lupine anthracnose is a severe fungal disease caused by Stagonosporopsis lupini, which significantly threatens lupin production worldwide. The pathogen is highly virulent and can cause extensive crop failure, particularly in susceptible cultivars when environmental conditions favor fungal proliferation.

The disease affects all parts of the lupin plant, including stems, leaves, petioles, and pods. Infection at the early vegetative stage often leads to seedling damping-off, while infection during the reproductive phase severely compromises pod development and reduces the overall yield quality and quantity.

Initial symptoms are characterized by small, reddish-brown necrotic spots that expand into sunken, dark lesions. Under high humidity, these lesions often produce salmon-pink or orange masses of conidia. Stem girdling and severe curling are common, often leading to lodging and the total breakage of the main stalk before maturity.

Environmental conditions play a critical role in disease development. Stagonosporopsis lupini thrives in warm temperatures combined with high relative humidity or frequent rainfall. These conditions facilitate the splash-dispersal of spores from soil debris and infected plant tissues to healthy foliage.

Integrated management is essential for controlling this pathogen. Key strategies include the use of clean, certified seeds and systematic fungicide seed treatments. Implementing a minimum 3-year crop rotation is crucial to break the disease cycle, as the pathogen can persist on infected crop residues in the field for several growing seasons.