Resumo

GONZALEZ, A  e  TRUJILLO, G. Susceptibility of Vasconcellea cauliflora to Papaya ringspot virus. Rev. Fac. Agron. [online]. 2005, vol.22, n.3, pp.229-240. ISSN 0378-7818.

This work demonstrated the susceptibility of Vasconcellea cauliflora, a species considered as virus resistant to Papaya ringspot virus (PRSV-P). Disease transmission by mechanical inoculation of PRSV-P severe strain on 60 days old plants was corroborated. Under greenhouse conditions with average values of 25.15ºC and 78.68% RH, 8.3% of plants inoculated with the severe strain showed apical necrosis. At the Facultad de Agronomía (UCV), Maracay (440 msnm) under field conditions, 8.6% of inoculated plants showed typical symptoms of the disease seven days after beings transplanted. Subsequently, an inoculation test was done in three growth chamber conditions: T1=29ºC and 6300 lux; T2= 27ºC and 5500 lux and T3= 25ºC and 4200 lux; the daily time was fixed at 16 h, and the relative humidity was about 75.5% on average. Systemic symptoms were observed in 82, 86 and 47% of plants in treatments T1, T2 y T3 respectively. These results were consistent with the ELISA test. The susceptibility of V. cauliflora to the local severe strain of PRSV-P was influenced by temperature and light intensity conditions. This questions the role of this species in search for PRSV-P resistance genes in papaya breeding programs.

Palavras-chave : Vasconcellea cauliflora; virus resistance; PRSV-P; ELISA.