Early Warning Systemfor management of Coffee Leaf Rust

The problem: Coffee Leaf Rust in Jamaica

• CLR is caused by the fungus Hemieleia vastrix which infects coffee leaves and produce millions of spores.

• High levels of infection can kill the leaf

which falls off the plant reducing the amount of food available for coffee berries to develop.

• Defoliation of coffee plants caused by the CLR fungus reduces coffee yields.

Effects of CLR in Jamaica

• Jamaican Coffee Industry lost US$5 million in revenue to CLR disease from the 2012-2013 crop resulting in 30% of farm labour force being laid off.

• CLR outbreaks are highly dependent on climatic factors, health of coffee plant and crop phenology.

• CLR disease is also influenced by socio-economic factors which influence farmers’ decision to take preventative actions.

THE DISEASE TRIANGLE & PYRAMID

For a fourth factor such as humans, vectors and time

Source: Francl L. J. (2001). Plant Health Instructor.

Plant disease caused by a biotic agent absolutely requires the interaction of a susceptible host, a virulent pathogen, and an environment favorable for disease development. Disease is prevented by elimination of any one of these three components.

Spores deposited

Movement Germination

Spores germinated

Colonies established

Penetrationin the tissue

Spores disseminated

Dissemination

Spores produced

The Rust Life Cycle & some of the most important factors affecting it (Avelino et al., 2004)

Rain

Wind

Fruit load

Fruit load

Soil humidity

Soil humidity

Lesions

Colonization of tissue

Sporulation

Leafarea

Temperature

Temperature

Temperature16-18° C

Moisture on leaf

Moisture on leafSunlight

Parasitism Complete resistance

Complete resistance

Management of CLR in Jamaica Arabica typica is most preferred variety in Jamaica for its cup quality However, A. typica is susceptible to CLR Coffee rust must be managed as a continuous epidemic on a perennial

crop, Any factor that can reduce sporulation, spore dispersal, or infection,

even a small amount, can mitigate the epidemic. Good cultural management is paramount, healthy plants are more

tolerant to rust but there are no simple rules to follow. The varieties grown, the character of the soils, the amount and

distribution of rainfall, and numerous other factors all interact to dictate what is required to manage rust.

Climate Products Towards the Management of CLR in Jamaica

1. Bush Fire Index (KBDI)

2. Improved Rainfall Climatologies

3. Improved Extreme Rainfall Diagnostics / Forecasting

4. Improved Seasonal Rainfall Prediction

• All of the above result from feedback from focus study groups and institutional stakeholders

2. Improved Rainfall Climatologies

15 station 10-year continuous observations (no missing days) 55 stations represented in 10 year record, but with scattered missing days

Weather station locations used in analysis

Interpolated maps

Modeled high resolution gridded map based on the 55-stations AND elevation.• Custom tailored: contours, colors, regions, etc…

3. Improved Extreme Rainfall Diagnostics / Forecasting

May 25, 2004

June 9, 2002

Hurricane Sandy backward trajectory

4. Improved Seasonal Rainfall Prediction

tradewinds

Sea temp gradients

Integrate new regional predictors based on weather-scale diagnostics

QUESTIONS?