ANTAGONIST TEST OF THE ENDOPHYTIC BACTERIA OF ARABICA COFFEE ROOT (Coffea arabica L.) AGAINST PATHOGENIC FUNGI Cercospora coffeicola BERK. & COOKE CAUSES OF LEAF SPOT DISEASE

The Arabica coffee plant (Coffea arabica L.) has an important role in Indonesia's national economy, both as a source of foreign exchange and income for around 1.5 million farmers. Indonesia's coffee production in 2021 reached 774.6 thousand tons, an increase of 2.75% compared to the previous year. However, coffee productivity often decreases due to attacks by plant pest organisms, especially leaf spot disease caused by the pathogenic fungus Cercospora coffeicola. The disease causes reddish-brown patches on the leaves and fruit damage, which can reduce yields by up to 30-50%. Until now, no resistant coffee cultivars have been found, so overall control is carried out with cultivation techniques and synthetic fungicides, which have the potential to cause negative environmental impacts and pathogen resistance. Alternatively, the use of endophytic bacteria as biological control agents shows great potential in inhibiting the growth of C. coffeicola. This study aims to test the ability of Arabica coffee root endophytic bacteria to control the pathogen biologically. The results are expected to provide environmentally friendly leafspot disease control solutions and support healthy and sustainable coffee production.