Managing Anthracnose in Olives

Anthracnose (Colletotrichum spp.)

Moderate-major problem. Causes soft circular rots on the fruit, and at high humidity produces an orange slimy mass of spores on the fruit surface. Commonly seen close to harvest when fruit softens. Transmission – survives on infected mummified fruit. Spores are spread by rain splash and wind. Can infect ripe fruit from new spores within 4 days.
Anthracnose infected flowers can lead to reduced fruit quality and premature fruit drop that reduces yield. When pressed the diseased fruit produce a turbid and acidic (High FFA) reddish oil of poor quality (defects: Musty / Humid / Grubby); the oil can be downgraded to a quality less than EVOO standard. 
Anthracnose is problematic for table olives because of impact on taste and appearance.

Current APVMA Permits

Note: These PERMITS provide for the use of a product in a manner other than specified on the approved label of the product. Unless otherwise stated in this permit, the use of the product must be in accordance with instructions on its label.

Permit ID

Description

Date Issued

Expiry Date

Permit holder

PER14908

Pyraclostrobin + Metiram (Aero) / Olives / Anthracnose

8-Jan-15

31-Mar-20

AOA

Withholding Period: 21 days.

Permit ID

Description

Date Issued

Expiry Date

Permit holder

PER14580

Azoxystrobin (Amistar) / Olives / Anthracnose

23-May-14

31-Aug-19

AOA

Withholding Period: 21 days.

Permit ID

Description

Date Issued

Expiry Date

Permit holder

PER11360

Copper (Copper present as Cupric Hydroxide, Cuprous Oxide, or Tribasic Copper Sulphate) / Olives / Fungal spots and rots including Peacock Spot and Anthracnose

24-Mar-2009

31-Mar-2017

AOA

Withholding Period: 1 day.

Further details on chemical permits available at: https://portal.apvma.gov.au/permits

Note: Victoria is not included in the above 2 permits, as their Control-of-Use legislation does not require a permit to legalise this off-label use in this state.

Meanwhile the search by Robert Spooner-Hart continues for a third systemic control option for Anthracnose:

In addition there are a number of registered (on label) copper oxychloride crop protectant products approved for use on olives:

Active ingredient

Chemical group

WHP, days

Activity   

Comments

copper oxychloride (Product # 63665, 68826, 59711)

M1

1

Contact, protectant

Registered. Commonly used in winter and spring.  2-4  applications/yr

Further label and MSDS details on registered products is available at:  https://portal.apvma.gov.au/pubcris  

Note: The use of registered products must be in accordance with instructions on its label.

FURTHER INFORMATION ON ANTHRACNOSE CONTROL OPTIONS:
Dr Vera Serveeva has kindly provided the following informative Powerpoint presentation covering diagnostic and research work on Anthracnose including Integrated Pest Management Strategies.

Anthracnose in Olives - Symptoms, Disease Cycles & Management

 

As well as the below paper on Anthracnose in olives: symptoms, disease cycle and management

Sergeeva V. | Proceedings of the 4th International Conference on “olive culture and biotechnology of olive tree products” Olivebioteq 2011. Chania, Greece,Vol.1, pp.269-274, 2012.

Anthracnose in Olives Article - Symptoms, Disease Cycles & Management

 

For further information on Dr Vera Serveeva work visit: http://olivediseases.com