Ken Y. Arakawa

The effect of the β-exotoxin fraction of Bacillus thuringiensis on the citrus red mite

Abstract Laboratory tests and a greenhouse study were conducted to determine the response of the citrus red mite to the β-exotoxin fraction of Bacillus thuringiensis . The results showed that the fraction produced high mortality in adult mites. Eggs and immature states were similarly affected. Greenhouse studies demonstrated that the test material was toxic for at least 45 days after application.

Protozoan parasites of species of Trogoderma in California

Abstract Diagnoses of diseases and/or parasite-host associations in populations of species of Trogoderma collected from locations throughout California were conducted between 1965 and 1968. The four species of parasites found associated with eight species of Trogoderma were members of the Protozoa, including the highly pathogenic Mattesia trogodermae, which was the most prevalent; an Adelina sp.; a cephaline eugregarine belonging to the genus Pyxinia; and an unidentified microsporidan. Data on host range of each parasite, distribution, and annual rates of parasitization over the 4-year period of the survey are presented.

The susceptibility of the eye gnat Hippelates collusor to entomogenous bacteria and fungi

Abstract A number of entomogenous bacteria and fungi were tested for their pathogenicity to the eye gnat Hippelates collusor. None of the bacteria at the concentrations used caused high mortality when tried against larvae. Those that were relatively more pathogenic, producing mortalities in the range of 40 to 60%, included Bacillus thuringiensis var. alesti, B. thuringiensis var. entomocidus, B. thuringiensis var. thuringiensis, a Bacterium sp. originally isolated from the house fly, and several pigmented strains of Serratia marcescens. The only fungus that possessed pathogenicity against the eye gnat was Beauveria bassiana. It caused up to 100% mortality in both adults and larvae and, therefore, appeared to the much more effective than the best of the bacteria that were tested.