Citrus producers in Minas Gerais should be on alert in the coming months

Spring and summer, the hottest periods of the year, bring with them a danger for citrus producers in the state of Minas: citrus canker. Easily and quickly spread, the pest causes damage to the quality of production and premature fruit drop, in addition to restricting trade to areas free of the disease. The most affected areas of the state are Zona da Mata, Vale do Rio Doce and Triângulo Mineiro.

In 2022, the Minas Gerais Agricultural Institute (IMA), a body linked to the Secretariat of Agriculture, Livestock and Supply (Seapa), received notifications about suspected citrus canker in the cities of Dona Euzébia and Astolfo Dutra, in the Zona da Mata region. These cities do not produce citrus, but they produce seedlings and from there came plants infected with the bacteria that cause the disease.

At that time, IMA visited all seedling nurseries in the region and around 1 million infected plants were eradicated. These properties were closed for more than 180 days, in accordance with current legislation. Despite the drastic measure, the action was necessary, as the outbreaks could quickly spread throughout the state's production. 

The work bore fruit, as in 2023 only two properties continued to have the disease, albeit in a controlled manner. “We are constantly appealing to producers to carry out regular inspections of their properties to make sure they are free from the disease and, if they notice any signs, to report it to IMA”, says Leonardo do Carmo, agronomist and head of the Health Defense Management IMA vegetable.

According to the agronomist, producers fail to notify IMA of suspected disease for fear of having their production destroyed, however, the faster they act, the less damage they will incur. “If the disease is discovered early, there are chances of saving production”, says Leonardo.

Today, 88% of citrus production in Minas Gerais comes from properties with less than 10 hectares, that is, small producers. The IMA forms partnerships with regional entities so that the health information recommended by the body is replicated in order to reach more producers, especially small and mini-producers.

Since 2022, IMA has intensified its actions to eliminate citrus canker in the state. Among these activities are the increase in the number of inspections in citrus seedling production areas, the increase in the number of blitzes in the citrus corridors of Minas Gerais, both at the entrance and exit of the state, to prevent the transit of plant loads from spreading pests. Furthermore, IMA has been raising awareness among the population through lectures and investing in training its technical staff to quickly respond to notifications of suspected infection in orchards.

Although Zona da Mata, Sul de Minas and Triângulo Mineiro are the largest citrus producers, the entire state of Minas has these plant species, so care is not restricted to these regions, but to the entire territory. To give you an idea, Minas Gerais is the second largest citrus producer in Brazil and Brazil is the largest producer of these fruits in the world.

Fast propagation

Citrus canker can spread through wind, rain, contaminated agricultural equipment and even insects. Favorable conditions for the development of bacteria are temperatures between 25° and 30°. For this reason, the months from September to March are the most dangerous.

“The ease with which the plague spreads is what concerns us most. To give you an idea, when IMA technicians visit a property where production is contaminated by citrus canker, or even suspected of it, they have to disinfect their clothes and vehicles before visiting another property”, reveals the agricultural engineer, Leonardo do Carmo.

The appearance of citrus canker is signaled by small yellow pustules on the underside of the leaves. A few days later, it is possible to see a match, that is, a bulge on both sides of the leaf. The last stage is the contamination of the branches, which within a few days dry up and die.

Protective measures

The best way to protect a plantation is to buy healthy seedlings. Knowing the origin of the plants and whether they have adequate health documentation is essential. “The two main documents to ensure the good health of the seedlings are the Phytosanitary Certificate of Origin (CFO) and the Plant Transit Permit (PTV)”, explains the professional.

Another indication is to disinfect boxes used to accommodate the fruits, tools used to manage the plants and transport vehicles for these parts.

The IMA reinforces the need to communicate as soon as possible about the suspected disease in one of the agency's units spread across the state. Leonardo also remembers that “if the producer notices that a neighbor's production has citrus canker, he must also notify the IMA, as his orchard is also at risk of contracting the disease”.