Abstract: The toxicity of aqueous extracts of two plants,
Nicotiana tobacum and Eucalyptus globulus were investigated against second instar larvae of Lycoriella auripila, one of the most
important pests of button mushroom, using agar dilution technique.
Seven concentrations of aqueous extracts of both plants were applied
on second instar larvae and their mortality were evaluated after 24, 48 and 72 h. The obtained results revealed that aqueous extracts of N.
tabacum and E. globulus caused 77.55 and 72.5% mortality of larvae
of L. auripila at concentration of 4000 ppm after 72h, respectively. Toxicities of tobacco extract after 24, 48 and 72 h were 1.52, 1.85
and 1.70 times greather than eucalyptus, respectively. The estimated LC50 after 24, 48 and 72 h were 7316.5, 2468.5 and 2013.1 ppm for
tobacco and 64870.0, 6839.5 and 3326.4 ppm for eucalyptus, respectively. These plants merit further study as potential insecticides
for the control of L. auripila.
Abstract: White rust, caused by Albugo candida, is the most
destructive foliar diseases of persian cress, Lepidium sativum in Iran.
Application of fungicide is the most common method for the disease
control. However, regarding the problems created by synthetic
pesticides application, environmentally safe methods are needed to
replace chemical pesticides. In this study, the antifungal activity of
plant natural extracts was investigated for their ability to inhibit
zoospore release from sporangia of A. candida. The crude extract of
46 plants was obtained using methanol. The inhibitory effect of the
extracts was examined by mixing the plant extracts with a
zoosporangial suspension of A. candida (1×106 spore/ml) at three
concentrations, 250, 100 and 50 ppm. The experiments were
conducted in a completely randomized design, with three replicates.
The results of the experiment showed that three out of 46 plants
species, including, Rhus coriaria, Anagallis arvensis and Mespilus
germanica were completely inhibit zoospore release from
zoosporangia of Albugo candida at concentration of 50 ppm.