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Ciência Rural

On-line version ISSN 1678-4596

Cienc. Rural vol.46 no.9 Santa Maria Aug. 2016


Press Release

Research shows that PCR method is effective for detecting the bacterium Erwinia psidii in guava

Marisa Álvares da Silva Velloso Ferreira2  * 

1UnB, Campus Darcy ribeiro IB bloco C térreo, Brasilia, DF, Brazil

Researchers at the University of Brasilia (UNB) and Embrapa Quarentena Vegetal, in Brasília, Brazil showed that the PCR method is effective for detecting the presence of the bacterium Erwinia psidii, causal agent of drought in Guava pointers. The study was published in Ciência Rural journal, v.46, n.9, September 2016.

The aim of the study was to evaluate the use of BIO-PCR and conventional PCR to detect E.psidii in plants inoculated in the greenhouse and in symptomatic and asymptomatic plants in guava orchards. For this, the researchers inoculated the IBSBF 1576 E.psidii strain in new shoots of guava plants, analyzing their tissue in the 0, 5, 10 and 15 days after inoculation. They observed symptoms after 5 days of inoculation. All inoculated plants were positive by PCR in all evaluated times. Under conditions of natural infection in the field, three orchards were evaluated by BIO-PCR. The researchers collected 40 samples of each orchard, 20 with and 20 without symptoms. PCR was positive in 58 of the 60 symptomatic samples (96.7%) and only 6.7% of asymptomatic samples. This demonstrates that the method can be used to detect bacteria in the initial stages of the infection.

According to the researcher Marisa Alvarez Velloso Ferreira da Silva, the results show that guava plants suspected to be contaminated with bacteria can be tested even before symptoms are visible. "This early diagnosis allows the producer to take control measures earlier or even prevent the introduction of bacteria in an orchard where the disease does not occur," says she.

The dry of pointers of guava is a limiting factor for the production of guavas, as it affects crop productivity. Like other diseases, its way of control is based on diagnosis, ie, the ability to detect the presence of the pathogen in culture. This study advances in this regard to be the first description of a molecular method to diagnose dry the hands caused by Erwinia psidii.

Researcher: Marisa Alvares da Silva Ferreira Velloso

Creative Commons License This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.