Analysis of the presence of viruses in garlic seed produced by thermotherapy culture and tissue

Author(s)

Milena Leite de Oliveira ^[1] ; João Paulo Calore Nardini ^[2] ; Bruno Rossito De Marchi ^[3] ; Tatiana Mituti ^[4] ; Daiana Bampi ^[5] ; Marcelo Agenor Pavan ^[6] ; Renate Krause-Sakate ^[7]

Affiliation

^[1] UNESP. Faculdade de Ciências Agronômicas. Departamento de Proteção Vegetal

^[2] UNESP. Faculdade de Ciências Agronômicas. Departamento de Proteção Vegetal

^[3] UNESP. Faculdade de Ciências Agronômicas. Departamento de Proteção Vegetal

^[4] UNESP. Faculdade de Ciências Agronômicas. Departamento de Proteção Vegetal

^[5] UNESP. Faculdade de Ciências Agronômicas. Departamento de Proteção Vegetal

^[6] UNESP. Faculdade de Ciências Agronômicas. Departamento de Proteção Vegetal

^[7] UNESP. Faculdade de Ciências Agronômicas. Departamento de Proteção Vegetal

• Document type: Journal article
• Source: Summa Phytopathologica; v. 40, n. 1, p. 75-77, 2014-03-00.

Abstract

The garlic (Allium sativum L.) can be naturally infected by a complex of filamentous viruses belonging to the genera Potyvirus, Carlavirus and Allexivirus. Accumulation of these viruses occurs especially by vegetative propagation through cloves. As the cultivated garlic plant does not produce true seed worldwide, virus-free plants can only be obtained by tissue culture of stem apices and thermotherapy. Using these techniques, garlic seeds were produced at the School of Agricultural Sciences - UNESP, Botucatu, and evaluated by RT-PCR for the presence of potyvirus, carlavirus and allexivirus. In the second generation of microcloves propagated in a greenhouse, 6.6% infection was detected, only by allexivirus. In the fourth generation, however, there was 60% incidence by allexivirus, 35% by potyvirus and all negative by carlavirus. The high rate of infection by allexivirus may be related to the greater difficulty of removing the species of viruses belonging to this genus, as observed by other authors, and also based on the infection and transmission of the virus by the mite, Aceria tulipae, during the storage of bulbs from one year to the other. The garlic at the fourth generation corresponds to cloves weighed less than 1 gram and not selected for commercial multiplication. Selection for the size of cloves has a positive effect on the choice of cloves with lower rates of viral infection, as the technique of thermotherapy and tissue culture do not eliminate the virus completely. Results also emphasize the need of fumigation for the garlic seed stored from one year to the other in order to prevent the transmission of allexivirus during storage. (AU)

• FAPESP's process: 10/15370-0 - Characterization of the Allexivirus present in garlic from South and Southeast Brazil and analysis of the presence of virus in the garlic produced by tip meristem in the FCA/UNESP.
• Grantee: Renate Krause Sakate
• Support Opportunities: Regular Research Grants