A program for the intensive production and protocols optimization for the production of virus-free garlic plants

CONCI V. C.,; PEROTTO M. C.,; CAFRUNE E.,; LUNELLO P.,; BRACAMONTE R.,; ALOCHIS P.,; NOME S. F

Beijin, China

Simposio; 4th International ISHS Symposium on Edible Alliaceae (ISEA).; 2005

Garlic is affected by a virus complex including mainly Potyvirus, Carlavirus and Allexivirus. These produce a reduction of 78% of bulb weight. Annually are subject to virus free process new cultivars selected by its agronomic qualities. Thermotherapy is evaluated for each cultivar and according results is applied, or not, before meristem extraction. Each plant obtained in vitro is evaluated by immmunosorbent electron microscopy plus decoration (ISEM-D) with the following antisera: Onion yellow dwarf virus (OYDV), Leek yellow stripe virus, Garlic common latent virus, Shallot latent virus, Garlic mite borne filamentous virus, and “mix-antisera” (obtained from garlic infected with the virus mixture which infect this crop naturally). Frequently, in this step, IC-RT-PCR or RT-PCR is used. The garlic plants obtained are classified in 2 categories: OYDV virus-free garlic plants, and virus-free garlic plants from all viruses detected with the antisera before mentioned. Both categories of plants are in vitro micropropagated with an increase rate each two months of 1.1–10 variables according the cultivar and the multiplication number. The hardening procedure starts in vitro with subculture at especial medium for either bulblet induction or more vigorous plant that tolerates the soil transplant. The in vitro bulblets obtained are planted in sterile soil. The plants which did not form bulbs are transferred to soil and kept in wet chamber between 15 and 20 days and then they are gradually adapted to natural conditions. The ex vitro plants are kept under gauzehouse until the cultivar cycle is completed. The following multiplications are carried out under gauzehouse where the plants are analyzed, one by one, by DAS-ELISA and the doubtful by ISEM-D. After that they are given to growers who carry out the multiplication in isolated areas from Alliaceae cultivars until they get enough bulbs to start a commercial production. The success of this procedure is tested periodically by DAS-ELISA to define the efficiency.