Insect-pest mobility can influence insect susceptibility to the insecticides used to control them. The objective of this work was to evaluate the flight activity of Sitophilus oryzae (L) and Sitophilus zeamais Motsch populations reared on corn and wheat grains, and its relationship with insecticide susceptibility. Unsexed adult insects with ages between 10 and 20 days were placed on a plastic t...

The spermiogenesis of Sitophilus zeamais and Sitophilus oryzae, the maize and the rice weevil, respectively, was studied by light microscopy and scanning and transmission electron microscopy. Sitophilus spp. is the most widespread and destructive primary pest of stored cereals in the world. The spermiogenesis occurs within cysts. There are approximately 256 germ line cells per cyst. Inside each...

COX II containing a dual core CuA active site is one of the three core subunits of mitochondrial Cco, which plays a significant role in the physiological process. In this report, the full-length cDNA of COXII gene was cloned from Sitophilus zeamais, which had an ORF of 684 bp encoding 227 amino acids residues. The predicted COXII protein had a molecular mass of 26.2 kDa with pI value of 6.37, a...

Laboratory tests were carried out in order to examine competition among three congeneric species on rice and maize: the granary weevil, Sitophilus granarius, the rice weevil, Sitophilus oryzae and the maize weevil, Sitophilus zeamais. For this purpose, a total of 30 adults were placed in vials that contained 50 g or either rice or maize: 30 adults of S. granarius, 30 adults of S. oryzae, 30 adu...

The effects of exposure period and phosphine concentration were quantified in adults of representative strains of Sitophilus zeamais (Motsch.), Sitophilus oryzae (L.) and Rhyzopertha dominica (F.) from China. All three species are major pests of stored grain in China. Although phosphine resistance is common in Chinese S. oryzae and R. dominica, with some very resistant populations, it is not pr...

The essential oil of Illicium simonsii fruit was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 40 components of the essential oil were identified. The principal compounds in I. simonsii fruit essential oil were β-caryophyllene (10.30%), δ-cadinene (9.52%), methyl eugenol (8.94), β-elemene (5.84%), and α-amorphene (5.20%). The essential oi...

In this study, we investigated the insecticidal activities, including contact toxicity, fumigant toxicity, and repellent activity, of Litsea cubeba fruit extracts against Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae). The extracts, obtained by liquid-liquid extraction in n-hexane, ethyl acetate, chloroform, and water were analyzed by gas chromatography-mass spectrometry. Among the ...

The screening of several Chinese medicinal herbs for insecticidal principles showed that Euphorbia fischeriana roots possessed significant feeding deterrent activity against two stored-product insects (Tribolium castaneum and Sitophilus zeamais). From ethanol extract, four feeding deterrents were isolated by bioassay-guided fractionation. The compounds were identified as jolkinolide B, 12-deoxy...

new sources of maize resistance to the maize weevil, sitophilus zeamais infestation are indispensable in successful breeding programs against post harvest grain damage. the study investigated the characters and mechanisms that confer resistance to weevil infestation using twenty elite maize genotypes. detailed morphological and physical studies were conducted on whole-maize grain. the grain hul...

In our screening program for new agrochemicals from local wild plants, Artemisia capillaris and A. mongolica were found to possess insecticidal activity against the maize weevil, Sitophilus zeamais. The essential oils of aerial parts of the two plants were obtained by hydrodistillation and were investigated by GC and GC-MS. The main components of A. capillaris essential oil were 1,8-cineole (13...