%0 Journal Article
%T Effect of essential oils of medicinal plants on leaf blotch in Tanzania grass Efeito de 車leos essenciais de plantas medicinais sobre a helmintosporiose do capim Tanzania
%A Gil Rodrigues dos Santos
%A R迆bia Borges Cruz Sarmento Brum
%A Henrique Guilhon de Castro
%A Clebson Gomes Gonˋalves
%J Revista Ci那ncia Agronˋmica
%D 2013
%I Universidade Federal do Cear芍
%X Leaf spots caused by phyto-pathogenic fungi, can reduce the production of forage plants. The essential oils of medicinal plants have antimicrobial potential. The objective here was to evaluate the fungotoxicity in vitro of the essential oils of lemongrass (Cymbopogon citratus (DC.) Stapf (Poaceae)), citronella (Cymbopogon nardus (L.) Rendle (Poaceae)), lemon balm (Lippia alba (Mill.) NE Br ex Britton & P. Wilson (Verbenaceae)) and peppermint (Mentha piperita L. (Lamiaceae)) on the fungus Helminthosporium sp. and the in vivo effect of these oils and of commercial neem oil (Azadirachta indica A. Juss. (Meliaceae)) on leaf blotch in Panicum maximum Jacq. cv. Tanzania-1. The mycelial growth of the fungus was evaluated over five periods (2; 4; 6; 8 and 10 days from incubation) and with five concentrations of essential oils (C1 = 250 ppm; C2 = 500 ppm; C3 = 750 ppm; C4 = 1,000 ppm e C5 = 1,250 ppm). As an alternative control, the preventative and curative effect on leaf blotch of five oil-based treatments were evaluated: lemongrass, citronella, lemon balm, peppermint and neem in four concentrations (2,500; 5,000; 7,500 and 10,000 ppm). The essential oils of lemongrass and citronella were the most effective in reducing mycelial growth of Helminthosporium sp. With the essential oil of lemongrass, the pathogen presented the highest growth concentration (1.250 ppm). The results obtained showed that all the essential oils and concentrations tested presented a preventive and curative effect, reducing the severity of leaf blotch. Manchas foliares, causadas por fungos fitopatog那nicos, podem reduzir a produ  o de forrageiras. 車leos essenciais de plantas medicinais apresentam potencial antimicrobiano. Objetivou-se avaliar a fungitoxicidade in vitro dos 車leos essenciais de capim-lim o (Cymbopogon citratus (DC.) Stapf (Poaceae)), citronela (Cymbopogon nardus (L.) Rendle (Poaceae)), erva-cidreira (Lippia alba (Mill.) N.E. Br. ex Britton & P. Wilson (Verbenaceae)) e hortel -pimenta (Mentha piperita L. (Lamiaceae)) sobre o fungo Helminthosporium sp. e o efeito in vivo desses 車leos e do 車leo comercial de nim (Azadirachta indica A. Juss. (Meliaceae)) sobre a helmintosporiose de Panicum maximum Jacq. cv. Tanzania-1. Foi avaliado, em cinco per赤odos (dois, quatro, seis, oito e dez dias de incuba  o), o crescimento micelial do fungo sob cinco concentra  es dos 車leos essenciais (C1 = 250 ppm; C2 = 500 ppm; C3 = 750 ppm; C4 = 1000 ppm e C5 = 1250 ppm). Como controle alternativo, foi avaliado o efeito preventivo e curativo sobre a helmintosporiose de cinco tratamentos 角 base de 車leo
%K Plantas forrageiras
%K 車leos essenciais
%K Helminthosporium sp.
%K Forage plants
%K Essential oils
%K Helminthosporium sp.
%U http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902013000300022