Disinfection of cuttings and of soil with eucalyptus oil on Peruvian carrot yield

Foi estudado o efeito do óleo de eucalipto na desinfecção de mudas e do solo sobre a produção e no controle de doenças durante o ciclo de cultivo da mandioquinha-salsa ‘Amarela de Carandaí’. Os tratamentos originaram-se do fatorial 2 (sem-MS e com-MC desinfecção das mudas em solução aquosa com 1% do óleo, por 35”) x 3 (sem-SSPOE e com-SCPOE pulverização do solo, antes ou depois do plantio, com solução aquosa com 2% do óleo). Foram realizadas colheitas das plantas aos 224 e 266 dias após o plantio-DAP. As massas frescas de folhas, rebentos e coroas foram semelhantes estatisticamente dentre as MS mas, dentro das MC, os maiores valores corresponderam às plantadas em SCPOE. As maiores produções de raízes comerciais aos 224DAP (5,94 e 6,90 t ha-1) e aos 266DAP (7,07 e 7,47 t ha-1) foram dos tratamentos onde as MS e MC foram plantadas em SCPOE antes do plantio. Foram observados sintomas de queima das folhas (associação de Alternaria sp. e de Septoria sp.) e de podridões das coroas e dos rebentos (Sclerotium sp.). Concluiu-se que, para se obter maior produção de raízes comerciais da mandioquinha-salsa, usando mudas desinfetadas ou não, deve-se pulverizar óleo de eucalipto no solo antes do plantio, embora sem esperar efeito sobre doenças foliares e podridões de final de ciclo.The effect of eucalyptus oil as disinfectant of cuttings and of soil on yield and disease control during cultivation cycle of ‘Amarela de Carandaí’ Peruvian carrot, was studied. Treatments were originated from 2 (without-MS and with MC disinfection of cuttings in aqueous solution with 1% of oil, for 35”) x 3 (without-SSPOE and with-SCPOE sprinkling on the soil, before and after planting, with aqueous solution with 2% of oil) factorial scheme. Harvests were done on 224 and 266 days after planting-DAP. Fresh masses of leaves, shoots and crowns were similar statistically among MS but, among MC, the highest values corresponded to those planted in SCPOE. The highest yields of commercial roots on 224DAP (5.94 and 6.90 t ha-1) and  266DAP (7.07 and 7.47 t ha-1) were from treatments where MS and MC were planted in SCPOE before planting. Symptoms of burning leaves (association of Alternaria sp and of Septoria sp) and of rot of crows and shoots (Sclerotium sp) were observed. It was concluded that, in order to obtaining a greater yield of commercial roots of Peruvian carrot, using cuttings that were disinfected or not, eucalyptus oil must be sprinkled on soil before planting, although without waiting effects on foliar diseases and rots at the final of the cycle