Virus eradication in Lily by combination of in vitro culture techniques

CHINESTRA, CAROLINA; MARINANGELI, PABLO; CURVETTO, NÉSTOR

Pescia, Toscana, Italia

Simposio; 2nd International Symposium on Genus Lilium; 2010

International Society for Horticultural Science

In order to eradicate Lily symptomless virus (LSV), Lily mottle virus (LMoV) and Cucumber mosaic virus (CMV) in lily, chemotherapy and thermotherapy were assayed in vitro prior to meristem tip culture in infected bulbs of Triumphator hybrid. After two in vitro multiplication cycles in darkness, bulb scales were divided longitudinally and cultivated at 25°C or 35°C on MS medium supplemented with 0.03 mg L-1 ANA with or without 20μM ribavirin (Virazole ®). Half of the regenerated bulbs were planted ex vitro and after two months the leaves were tested for the viruses by DAS-ELISA. The remaining bulbs were used for meristem tip culture on MS medium at 25ºC and 16 h photoperiod (RFA 48 umol cm-2.s-1). After six months, bulbs were planted ex vitro and when leaves developed they were screened for viruses. Thermotherapy at 35°C caused browning of scales and death. Scales at 25°C presented a high percentage of bulbs regeneration (97%). In vitro culture prior to meristem culture produced virus eradication with different efficiency. Infection with LMoV was 28.9 % and 34.6% with and without meristem tip culture, respectively. Infection with LSV was 4.4% and 67.3% with and without meristem tip culture, respectively, with significant differences between treatments (p<0.05). CMV was not detected in plants after treatments. No differences between chemotherapy and the control were found (p>0.05) for the three viruses. The release of virus in lilies depends not only on treatment but also in the virus involved.