Phytosanitary status of Huanglongbing in Santa Catarina

Resumo

Citrus production in Santa Catarina has been notable for the cultivation of oranges and mandarins intended for fresh consumption. Huanglongbing (HLB) has been recently reported in the state and, due to its highly destructive nature, poses a significant threat to citrus production systems, which are predominantly based on smallholder farming. According to the National Program for the Prevention and Control of HLB, in states where the disease occurs, the State Plant Health Protection Agency is required to delimit and report to the Superintendence of Agriculture and Livestock the municipalities with and without HLB occurrence, based on technical evidence. This process includes the detection of the associated pathogen Candidatus Liberibacter asiaticus, thereby supporting phytosanitary classification and informing disease management strategies. In Santa Catarina, Huanglongbing (HLB) was first detected in 2022 in the municipality of Xanxerê. Since then, systematic and continuous surveys have been conducted by Epagri and Cidasc in citrus orchards across the state to detect the occurrence of HLB in orchards with suspected infection. For this purpose, plant material from suspected trees was collected and submitted to a private laboratory for the detection of Ca. L. asiaticus by qPCR. Up to May 2026, the occurrence of Huanglongbing (HLB) has been confirmed in seven municipalities (Abelardo Luz, Guaraciaba, Ipuaçu, São José do Cedro, São Lourenço do Oeste, São Miguel do Oeste, and Xanxerê). An additional nine municipalities presented suspected focus and are currently under investigation and subjected to contingency actions (Bom Jesus, Chapecó, Coronel Martins, Descanso, Galvão, Guarujá do Sul, Guatambu, Jupiá, and São Domingos). All the aforementioned municipalities are located in the Western geographic mesoregion of Santa Catarina, most of them bordering the state of Paraná and Argentina, which are regions where HLB is already widespread. This pattern of incidence suggests that HLB may have entered Santa Catarina through infective psyllids migrating from those regions. In light of this, monitoring and contingency actions are being carried out in municipalities with confirmed occurrence, as well as in adjacent municipalities, in order to curb the spread of HLB and preserve citrus production in Santa Catarina.