Bioassays were carried out in the laboratory to determine the virulence of two Beauveria bassiana indigenous isolates on the greater wax moth Galleria mellonella. LC50 and LT50 values were taken as indices for the efficacy of fungal isolates, designated as Bb1 and Bb2, collected from Ismailia governorate in Egypt and isolated from soil and trap larvae of G. mellonella, respectively. The larvae ...

subterranean termites are one of the most important pests of buildings, historic monuments and agricultural crops in some parts of iran. using entomopathogenic fungi as microbial insecticides is usually a part of biological control and insect pest management. the pathogenicity of entomopathogenic fungus, metarhizium anisopliae (metschnikoff) sorokin (demi 001) isolated from rhynchophorus ferrug...

A model based on the concept of reduction in life expectancy (RLE model) as a result of long term exposure to toxicant has been developed which has normal life expectancy (NLT) as a fixed limiting point for a species. The model is based on the equation (LC50 = a ln(LT50) + b) where a and b are constants. It was evaluated by plotting ln LT50 against LC50 with data on organic toxicants obtained f...

Spodoptera exigua (Lepidoptera: Noctuidae) is one of the major pests of many crops in Pakistan. Effectiveness of different insecticides was evaluated against field populations of 2 instar larvae of S. exigua under laboratory conditions because in lepidopterous pests resistance is developed in 3 instars. Bioassays were performed through leaf dip method to evaluate the doseand time-mortality resp...

A phototoxic target lipid model (PTLM) is developed to predict phototoxicity of individual polycyclic aromatic hydrocarbons (PAHs) measured either as median lethal concentration (LC50) or median lethal time (LT50) for a 50% toxic response. The model is able to account for the differences in the physical/chemical properties of PAHs, test species sensitivities, and variations in light source char...

The adulticidal activity of methanol extracts from three Malaysian plants namely Acorus calamus Linn., Litsea elliptica Blume and Piper aduncum Linn. against adult of Aedes aegypti (L.) were studied. Standard WHO bioassay tests were used to evaluate the effectiveness of these plant extracts. The hexane fraction from methanol extract of Acorus calamus rhizome was the most effective, exhibiting L...

Spilarctia obliqua nucleopolyhedrosis virus (SoNPV) has been found effective against S. obliqua (Walker) as well as Porthesia xanthorrhoea Kollar. LC50 concentration of S. obliqua SoNPV against S. obliqua and P. xanthorrhoea was 2.5 x 10(4) and 3.7 x 10(4) POBs/ml, respectively. LT50 of SoNPV against S. obliqua was 5.73 days, while it was 6.98 days for P. xanthorrhoea. Cross infectivity of SoNP...

Fumigant toxicity and sublethal effects of essential oils from Artemisia khorassanica Podl. and Artemisia sieberi Bess were investigated against adults of Sitotroga cerealella Olivier. To assess the sublethal effects, adult moths were exposed to the LC30 of each essential oil, and life table parameters of the surviving S. cerealella were studied. Higher fumigant toxicity of A. khorassanica (LC5...

Background: There are several plant extractions which are being used for mosquito control. The aim of this study was to evaluate the efficacy of Olea vera, Linum usitatissimum and Piper nigera against Anopheles stephensi and Aedes aegypti under laboratory conditions. Methods: These tests were carried out using WHO recommended bioassay method for adult mosquitoes. Results: The extracts from blac...