Honduras is facing what is possibly a new outbreak of coffee leaf rust. There are reports that this incidence is of a new race of the fungus that is able to infect the Lempira breed of coffee shrubs that is resistant to previously known races1.
The national level of infection is currently at around 6%, just below the threshold for triggering a national, early warning system. However, early observations show that a significant percentage of Lempira shrubs (10% of those surveyed) are already infected2.
Read more about coffee leaf rust in these tweets
Honduras has previously experienced a significant outbreak and as a result, they developed a national system to respond to new outbreaks. The fact that the majority of coffee farmers in Honduras are small holders presents a few challenges; more producers means more coordination and smallholders tend to have fewer resources (finances, labor, technical knowledge, etc) with which to respond to a local outbreak, but the small size of their plantations may make it easier to contain a local incidence (as long as their neighbors are also doing the right things).
The concerning part of this story is the fact that a tree that is resistant to previously known races of the fungus appears to be vulnerable. This seems to indicate we are looking at a new race of the fungus—there are currently around 50 known races. Resistant breeds are a farmer’s best defense but if they have depended heavily on a single breed that is suddenly discovered to be vulnerable, they can have significant exposure. For that reason, the best-prepared farms will be the ones that are anti-fragile, meaning they already have multiple breeds of shrubs planted and have systems in place to monitor and respond to the performance of each one. However, when experiencing a new race that is able to infect resilient breeds, farmers will be forced to respond with agrochemicals and/or stumping infected plants, two costly options.
There are also preventative and mitigating actions farmers can take; such as providing shade, ensuring good nutrition and good pruning practices, all of which help a shrub resist infection.
Honduras is hopefully in a good place to respond to what may become a national outbreak but the good news is the industry is watching closely and is already reacting.
Updated April 23, 2019: Embedded tweet and added link to Twitter search
1. http://www.laprensa.hn/economia/1059765-410/nueva-raza-de-roya-ataca-cafetales-de-8-departamentos ↩
2. https://www.perfectdailygrind.com/2017/06/how-is-honduras-responding-to-recent-coffee-leaf-rust-outbreak ↩