A team at the Instituto Nacional de Tecnología Agropecuaria - INTA Yuto in Argentina is implementing a molecular technique that allows the precise identification of the pathogen that represents a threat to citrus production and exports.

Citrus black spot, caused by the fungus Phyllosticta Citricarpa, is a constant concern for growers, especially in northern Argentina, because, on the one hand, it causes the affected fruit to fall prematurely and, on the other hand, it causes aesthetic damage that reduces its commercial value.

Faced with this problem, researchers from INTA Yuto are working on the rapid detection of the disease based on a protocol that focuses on the localization of the fungus, which allows a highly sensitive and accurate identification of the pathogen, the entity detailed in a press release.

"The main objective of this protocol is to provide the citrus industry with an effective and reliable tool for the rapid diagnosis of this devastating disease," said Ceferino Flores, researcher at INTA Yuto.

"We seek to avoid commercial losses at the time of export and protect the quality of our crops," he added.

INTA highlighted that the Phytopathology and Biotechnology Laboratories of INTA Yuto are key for diagnosing citrus black spots, accelerating the export process, and providing security to producers and exporters.

This achievement represents an important milestone in the fight against this disease and the protection of the Argentine citrus industry, being the only laboratory authorized to perform diagnostics using this technique in Salta and Jujuy.

"The technique used for the black spot is a real-time PCR , which, in addition to detecting a causative agent of an infection, informs us about the number of causative agents that exist, that is, it performs a quantification," said Flores.

"The detection is based on a protocol that focuses on localizing the fungus using primers and probes specifically designed for the ITS region of the 16S ribosomal DNA," he said.

PCR, which stands for 'Polymerase Chain Reaction', is a diagnostic test that detects a fragment of the genetic material of a pathogen and thus detects its presence in infected fruit.

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