In 1989, indole alkaloid okaramines isolated from the fermentation products of Penicillium simplicissimum were shown to be insecticidal, yet the mechanism of their toxicity to insects remains unknown. We therefore examined the action of okaramine B on silkworm larval neurons using patch-clamp electrophysiology. Okaramine B induced inward currents which reversed close to the chloride equilibrium...

The cry genes of Bacillus thuringiensis encode a diverse group of crystal-forming proteins that exhibit insecticidal activity, particularly against the larvae of lepidopteran, coleopteran, and dipteran insects. The efficacy of B. thuringiensis-based biopesticides may be improved through the genetic manipulation of these genes. A gene transfer system has been developed for the introduction and m...

Bacillus thuringiensis (Bt) Cry toxins have been used widely in pest managements. However, Cry toxins are not effective against sap-sucking insects (Hemiptera), which limits the application of Bt for pest management. In order to extend the insecticidal spectrum of Bt toxins to the rice brown planthopper (BPH), Nilaparvata lugens, we modified Cry1Ab putative receptor binding domains with selecte...

S. Gomathi and K.M. Subbu Rathinam* ABSTRACT To identify the insecticidal components of Saraca asoca bark were evaluated by standard protocol using the equipment Perkin-Elmer Gas Chromatography–Mass Spectrometry. The mass spectrum of the compounds found in the extract was matched with the National Institute of Standards and Technology (NIST) library. The GC-MS analysis revealed the presence of ...

The objectives of the present study were to investigate phytochemical composition essential oils (EO) from rhizomes Acorus calamus collected Jorhat, Assam; Munsyari and Pantnagar, Uttarakhand, India. EOs studied for different pesticidal activities viz; nematicidal, insecticidal, herbicidal activity. To synergistic effect on activity, four combinations prepared. Phenylpropanoids with β-asarone a...

A simple and selective assay system was developed in the search for new insecticidal substances from Actinomycetales strains propagated on solid culture media. The strains were first tested for their ability to produce antimicrobial compounds. Only strains displaying weak or no activity were retained and screened in the insecticidal bioassay. Microbial solid cultures were given as food to larva...