Abstract: The toxicity of four compounds belong to different groups of insecticides; chlorpyrifos, imidacloprid and their nano derived
were evaluated in the laboratory against larvae and adults of the red palm weevil, Rhynchophorus ferrugineus (Olivier), by
using dipping food technique. The results revealed that nanochlorpyrifos was the most toxic insecticide among the tested
compounds against the larvae, followed bychlorpyrifos, imidacloprid and nanoimidacloprid; LC50 values were 52.0, 126.1,
28.4 and 123.3 ppm for chlorpyrifos, imidacloprid, nanochlorpyrifos and nanoimidacloprid, respectively. The larvae were more
susceptible than the adults to most of the tested insecticides. Moreover, increasing time of exposure, the toxicity of imidacloprid
to both larvae and adults increased and also was more effective than nanoimidacloprid while the opposite situation was
obtained with nanochlorpyrifos. Determination of the shape and structure of chlorpyrifos and imidaclopridnano particles
was characterized by transmission electron microscopic (TEM). The activity of pesticides was determined through Fourier
Transform Infrared Spectrometry (FTIR) to obtain number of active terminals. Then field studies was done, it was carried out
in the orchard of Research Station of the Agricultural Research Center Giza Governorate, Egypt to evaluate the efficiency of
the field-based nano-chlorpyrifos pesticide compared to chlorpyrifos on both larvae and adults according to the highest
obtained laboratory results at a concentration of 500 ppm. Four infested palm trees with red palm weevil for each treatment
have been identified by using RPW detection device as well as visual detection. The pesticide solution was injected into 3
holes against larvae and adults of red palm weevil. Chlorpyrifos and their nano derived were applied at a rate of 1 liter per palm
the treated palm trees were monitored weekly to determine the date palm that was recovery, which recorded after 21-30 days.
The results showed that the efficacy of nanochlorpyrifos in the recovery of infected palms by stopping oozing brown fluid.
Publication year 2019
Organization Name
Author(s) from ARC
Publication Type Journal