Óleos essenciais no controle de Fusarium sp. na cultura do coentro

Abstract

Coriandrum sativum L. Cilantro has great importance because it is commonly used in the Brazilian menu, and its production is very relevant in agricultural Activities. The pathogenic fungus Fusarium sp. is known to cause root rot and wilt in more than 100 species of plants, is presented as one of the problems that affect the coriander culture. The objective of this study was to evaluate the in vitro and in vivo effect of essential oils on the growth and sporulation of Fusarium sp. in coriander (Choriandrum sativum L.) culture. The experiment was conducted in the laboratory of Phytopathology and Greenhouse, from the Agrarian Sciences Center of the Federal University of Paraíba (CCA/UFPB), sand, PB. Two assays were performed in vitro with the fungus Fusarium sp. and another in vivo in Coriandrum sativum L. Cilantro seeds. In the in vitro test the treatments were the basis of commercially acquired essential oils, these being: carnation, sesame, sunflower, copaiba, sweet herb; Were 100 μl of each oil for each 200 mL of culture medium 1% (V/V), plus two drops of Tween 80 (dispersing). The assay consisted of six treatments and nine replications in a completely randomized design, the variables evaluated in this test were: mycelial growth Velocity Index (IVCM), Mean colony diameter (DMC), percentage of inhibition of Mycelial growth (PIC), sporulation and percentage of sporulation inhibition (PIE) of Fusarium sp.. In the in vivo test the seeds were subjected to inoculation with spore suspension of 105 spores mL-1 of the pathogen Fusarium sp. For five minutes, after an interval of 24 hours of inoculation, as seeds were subjected to the same doses of essential oils in the in vitro test, diluted in 100mL of distilled water. The sweet herb oil stood out, reducing in 92 and 86% The percentage of inhibition of mycelial growth and percentage of inhibition of sporulation, respectively. The treatment with Copaiba oil reduced in 21, 54 and 65, 55%. From the in vivo test in greenhouse, it was possible to observe that coriander seedlings did not develop symptoms related to Fusarium sp. attack among the oils tested, the essential oil of sweet herb is the most efficient in reducing growth and sporulation In vitro of Fusarium sp. As it was not possible to evaluate the effect of treatments on seed germination, it is necessary to perform new testicles, to know if the essential oil of sweet herb can be used in the treatment of seeds for planting.