Lupin anthracnose

Current Situation

Updated July 2019

In October 2016 lupin anthracnose was detected for the first time in commercial crops in NSW in the eastern Riverina region. NSW DPI and LLS rapidly implemented a response plan to eradicate the disease. With cooperation from affected growers a case by case assessment of the infected crops was implemented to contain and control the disease. A lupin anthracnose biosecurity management zone was established, restricting the planting of lupins within the zone during the eradication response. Ongoing surveillance of lupin crops for the disease within the zone and across NSW continued for two growing seasons. No reoccurrence of the disease has been found in NSW crops and it has officially been declared Absent: pest eradicated.

Notifiable status

Lupin anthracnose (Colletotrichum lupini) is a notifiable plant disease in NSW.

All notifiable plant pests and diseases must be reported within 1 working day. You can report notifiable plant pests and diseases by one of the following methods:

Call the Exotic Plant Pest Hotline 1800 084 881
Email biosecurity@dpi.nsw.gov.au with a clear photo and your contact details
Complete an online form

A full list of notifiable plant pests and diseases can be found in Schedule 2 of the NSW Biosecurity Act 2015.

Symptoms

Symptoms of lupin anthracnose can be seen on all above ground parts of the host plant. If infection occurs early in the season lesions can be found on seedlings.

The most obvious symptom in lupins is bending and twisting of stems, known as the “shepherds crook”, which is particularly noticeable when the crop is flowering (Figure 1).

Oval shaped lesions occur on the stem and eventually lead to collapse and bending of stems. Lesions can be up to 2 cm in length and contain a bright orange/pink spore mass.

Main stems and lateral branches can be affected, with similar symptoms also found on leaf petioles.

Later in the season as the disease progresses, lesions can develop on the pods, distorting and twisting them. Infection of pods can lead to complete pod loss, and the production of infected seed. Infected seeds can be malformed, and have brown lesions on the surface. Seeds can also be infected without showing visible symptoms.

Disease lifecycle

Initial infection occurs from the fungus carried on or within infected seed. Seedlings emerging from infected seed may develop lesions.

Lesions produce an abundance of fungal spores which are spread through the crop by rain splash. The fungus can survive over summer on infected stubble and spores can be splashed to re-infect seedling lupins planted into infected stubble. Rain decreases the viability of the fungus on stubble making it less likely to survive through the following winter and spring conditions.

Spread

Infected seeds are the main source of spread of lupin anthracnose. The fungus can survive for up to two years on lupin seed and possibly longer under some conditions.

Lupin anthracnose can also be spread by infected stubble through rain splash, and movement of spores by contaminated machinery, vehicles, people, animals and fodder between lupin crops and cropping areas.

Hosts

All lupin species are affected, but generally albus lupin (Lupinus albus) and yellow lupin (L. luteus) are more susceptible than narrow leafed lupin (L. angustifolius).

Lupin anthracnose does not affect other broadacre crops.

World distribution

Lupin anthracnose occurs in all lupin growing countries of the world. It is the most damaging disease of lupins in Europe, North America, South America and New Zealand.

Australian distribution

Lupin anthracnose is established in Western Australia and has spread through wild populations of blue lupins (L. cosentinii). Lupin anthracnose has also been found in commercial lupin crops on the Eyre Peninsula and south east cropping regions of South Australia.

Market access and legislation

Regulations apply for the movement of lupin plant material, used packaging and used agricultural equipment into NSW. Details for this legislation are in the Biosecurity Regulation 2017 and the Biosecurity Order (Permitted Activities) 2017.

Actions to minimise risks

Five point management plan

These strategies are aimed at significantly reducing opportunities for establishment and spread of the disease.

Treat seed for sowing with a fungicide seed treatment containing thiram: Seed transmission is the main form of disease spread and survival between seasons. Treating lupin seed for sowing with a fungicide seed dressing containing thiram can significantly reduce the chances of anthracnose developing and becoming established. Be aware that seed applied fungicides can be deleterious to rhizobia. The best approach is to treat seed with fungicide, allow to completely dry then apply the rhizobia shortly before seeding, using an increased rate to ensure survival. Also be aware of the source of the lupin seed you are purchasing to sow for crops or to feed to livestock. Illegal imports of lupin seed from Western Australia have been found in NSW.
Separate this year’s lupin crop from last year’s lupin stubble: The fungus that causes anthracnose can survive in old infected lupin trash between seasons. New infections can arise if old infected lupin trash comes into contact with new season’s lupin crops. Prevent transmission of the disease from old stubble by separating this year’s lupin crop away from last year’s lupin stubble.
Control volunteer lupins on your property: Volunteer lupins can be a source of anthracnose for new season’s crops. Volunteer lupins can arise from within last year’s lupin paddock or from feeding lupin seed to stock over summer and autumn. They can host the anthracnose fungus and build up levels of disease inoculum between lupin crops.
Control machinery and people movement into and out of lupin crops: Spores of the anthracnose fungus can be carried by machinery, animals and human movement. Spores that develop during the growing season on infected plants can adhere and spread the disease within crops and between crops. Be aware of machinery movements into and out of lupin crops, particularly contractors. Be aware of human activities in crops and the possible risks involved. Outside contractors and people entering lupin crops should adhere to the principles of Come Clean. Go Clean.
Monitor lupin crops for symptoms of anthracnose: Lupin crops should be regularly monitored for symptoms of anthracnose. The most distinct symptoms of the disease are the bright orange/pink spore masses that form on infected tissue including stems and pods, especially during flowering and pod filling. Infections that form on the stem will cause the stem to collapse and bend into a distinct ‘shepherds crook’ symptom, these will form in patches within the crop. Bright orange/pink spores masses will form within the crook of the bend. Report any suspicious symptoms to the Exotic Plant Pest Hotline 1800 084 881.

Put in place biosecurity best practice actions to prevent entry, establishment and spread of pests and diseases:

practice “Come clean, Go clean”
ensure all staff and visitors are instructed in and adhere to your farm hygiene requirements
monitor your crop regularly
investigate sick plants
keep records
abide by legislation