The chemical composition of plant essential oils,
and the in vitro effect of plant extracts and plant essential
oils on the phytopathogens Bipolaris oryzae and Gerlachia
oryzae was investigated. Liquid extracts of ten plants were
obtained by maceration and then dialyzed using a 3kDa
retention membrane. The plant essential oils from seven
plants were analyzed by gas chromatography. To determine
anti-fungal activity two methodologies were used: Kirby-
Bauer and incubation. In this research we identified the major
compounds of the essential oils: 93.77 % β-thujone in the
Tanacetum vulgare oil; 40.61 % β-thujone in Artemisia
absinthium; 45.89 % nananone and 41.07 % undecanone in
Rutagraveolensand;38.78% citronelloland19.55% carvone
in Malva sp. This research showed that the Cymbopogon
citratus, P. alliacea, S. officinale and Malva sp. extracts have
more potential to control G. oryzae best while the S. officinale
and Lantana camara extracts are most efficient against B.
oryzae. Among the plant essential oils, Zingiber officinale, C.
citratusandMalvasp.hadthegreatestpotentialtocontrolboth
phytopathogens. This is the first report of the activity of plant
extracts and essential oils against the phytopathogens G.
oryzae and B. oryzae, two important pathogens of irrigated
rice.