Yield returns positive when using PROBLAD against Coffee Leaf Rust at the smallholder level in the San Francisco Bay Coffee Zone-Kigoma, Huye, Rwanda

It is June 11, 2020, after a month of drought followed by 9 consecutive months of rain, the coffee harvesting season is about to wrap up and it is now a good time to assess the farms that have been applied with PROBLAD monthly since June 2018. PROBLAD has shown to be effective protecting the trees from fungus if used in monthly spraying schemes, in addition there has been positive yield increases which means more returns to farmers.

The above photo shows how immediately after the application of PROBLAD, the urediospores desiccate after contact by PROBLAD. No more spores appear between 14-24 days after application and the trees retain their leaves. Furthermore, all trees sprayed with PROBLAD had a stable yield in two consecutive seasons.

A survey conducted on coffee farmers who trialled PROBLAD said the following,”

• When PROBLAD is applied, defoliation is reduced and the leaves have less coffee leaf rust compared to where PROBLAD was not applied.
• Farmers testify that coffee cherries ripen well in the PROBLAD applied parts of their farms compared to where PROBLAD was not applied.

A coffee farmer in Rwanda, Bon Fils said, “in the same conditions of his farm, PROBLAD was applied on 20 trees. The 20 trees treated with PROBLAD yielded 4 kgs per tree compared to 1.5 kg from the untreated trees. PROBLAD can be used during harvest and in this case was used during harvesting.

Another coffee farmer in Rwanda, Nyirarukundo Betty testified that after the application of PROBLAD, the leaves on her coffee trees looked greener, less coffee leaf rust was visibly present and many more coffee cherries were found compared to the coffee trees that was not treated with PROBLAD.

Looking at the SF Bay Coffee demo 1, the production per tree treated with PROBLAD has exceeded 8kg per tree and still picking is being made around June and July.

Summary:

From the review of the farmers in Rwanda at the San Francisco Bay Coffee Zone, the field observation of PROBLAD treated coffee trees indicates the following:

• PROBLAD helps coffee to reduce defoliation,
• PROBLAD dries the spores and keeps the coffee leaves green in the applied parts compared to the parts where PROBLAD has not been applied.
• The coffee trees look healthier once applied with PROBLAD which improves the flowering and increases the cherries thereby increasing farmers earnings.

It appears evident that severe coffee leaf rust comes after the harvest in July and August in Rwanda and is less visible in the raining period. PROBLAD is unique in that it can be applied at harvest when the epidemic signs are the most severe.

Recommendations:

• PROBLAD as a natural contact bio-fungicide can be used anytime by the farmers, even during harvest period.
• PROBLAD can help in disease management programmes to combat coffee leaf rust and coffee berry disease.

Dilution Rate:

The correct application rate was found at 20ml/L and the application can be made in every two weeks where severe coffee leaf rust is found.

Method of application:

• The mixed PROBLAD solution has to reach the under-leaf part because that is where coffee leaf rust spores develop.
• The coffee tree leaves must be drenched well with the PROBLAD solution as PROBLAD is a contact bio-fungicide.

The above data was compiled by Dr. Mario Serracin of San Francisco Bay Coffee and his team with the assistance of RAB based in Rwanda.

Dr. Joseph Bigirimana of RAB has been evaluating, trialling and testing PROBLAD and is still in the process of evaluating, trialling and testing PROBLAD with the aim to register PROBLAD for use on coffee in the near future.

Agropy U.K. would like to thank Dr. Mario, his team and Dr. Joseph Bigirimana of RAB and his team for their hard work and effort thus far.