Autor(es):
Oliveira, Helena 
; Rego, Cecilia ; Nascimento, Teresa ; Cabral, Ana ; Silva, Maria José
Data: 2009
Identificador Persistente: http://hdl.handle.net/10400.5/1520
Origem: Repositório da UTL
Assunto(s): cylindrocarpon; black foot disease; botryosphaeriaceae; chemical control
Descrição
Previous surveys conducted in commercial nurseries found that different wood fungi, namely Cylindrocarpon
spp., Botryosphaeriaceae, Phomopsis viticola and Phaeomoniella chlamydospora infect grapevine cuttings.
Two fi eld trials were carried out to evaluate the effectiveness of cyprodinil + fl udioxonil, pyraclostrobin + metiram,
fl udioxonil and cyprodinil to prevent or reduce natural infections caused by such fungi. Rootstock and scion cuttings
were soaked in fungicidal suspensions for 50 min prior to grafting. After callusing, the grafted cuttings were planted
in two commercial fi eld nurseries with and without a previous history of grapevine cultivation. After nine months in
the nursery, the plants were uprooted and analysed for the incidence and severity of the wood fungi. Plants uprooted
from the fi eld without a previous history of grapevine cultivation were generally less strongly infected by wood fungi.
Under this condition, only the mixture cyprodinil + fl udioxonil simultaneously reduced the incidence of Cylindrocarpon
and Botryosphaeriaceae fungi, as well as the severity of Cylindrocarpon infections. Treatments did not produce
signifi cant differences in the incidence and severity of P. viticola, and Pa. chlamydospora. For plants grown in the
fi eld with a grapevine history, all fungicides except cyprodinil signifi cantly reduced the incidence and severity of
Cylindrocarpon fungi. Also, the incidence and severity of Botryosphaeriaceae pathogens were signifi cantly decreased
both by cyprodinil + fl udioxonil and by cyprodinil. No signifi cant differences were noticed for P. viticola incidence and
severity, and Pa. chlamydospora was not detected again. These results suggest that the practice of soaking grapevine
cuttings in selected fungicides prior to grafting signifi cantly reduces Cylindrocarpon spp. and Botryosphaeriaceae
infections, thus improving the quality of planting material.
