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The effects of selective logging on the diversity and species composition of moths were investigated by sampling from multiple sites in primary forest, both understorey and canopy, and logged forest at Danum Valley, Sabah, Malaysia. The diversity of individual sites was similar, although rarefied species richness of logged forest was 17% lower than for primary forest (understorey and canopy combined). There was significant heterogeneity in faunal composition and measures of similarity (NESS index) among primary forest understorey sites which may be as great as those between primary understorey and logged forest. The lowest similarity values were between primary forest understorey and canopy, indicating a distinct canopy fauna. A number of species encountered in the logged forest were confined to, or more abundant in, the canopy of primary forest. Approximately 10% of species were confined to primary forest across a range of species' abundances, suggesting this is a minimum estimate for the number of species lost following logging. The importance of accounting for heterogeneity within primary forest and sampling in the canopy when measuring the effects of disturbance on tropical forest communities are emphasized.

Agricultural pest insects have been controlled primarily through the use of chemical insecticides. Bacillus thuringiensis (Bt) bacterium is an alternative for biological control since it synthesizes entomopathogenic protoxins which are codified by different cry genes. This study evaluated the insecticidal activity and the histopathological effects of bacterial suspension and purified Cry1Ba protein from B. thuringiensis thuringiensis strain 4412 in the midgut epithelial cells of S. frugiperda larvae. To accomplish that, bioassays were done with bacteriological suspension of the Bt strain, which was applied to the Poitout diet, and the toxicity of this strain was also determined by the LC₅₀, using purified protein, where the diet was substituted by disks of corn leaf. In the control group the protein and bacterial culture were replaced by sterile distilled water. S. frugiperda larvae of 2^nd instar were prepared through the inclusion paraffin techniques to evaluate the histopathology. Our results showed that the tested B. thuringiensis thuringiensis 4412, was highly toxic in the bioassays with 100% of corrected mortality to S. frugiperda larvae. In addition, the LC₅₀ results indicated that the expressed Cry1Ba protein was toxic too, with a LC₅₀ of 10.88 μg/ml. The histopathological analysis of S. frugiperda midgut showed a progressive loss of epithelial cell definition after 3h, in both treatments. At 24h post treatment, their midgut changes included vacuolization of the cytoplasm, hypertrophy of the epithelial cells, and vesicle formation in the apical region of both goblet and columnar cells. Also, the brush border membrane was damaged, especially in goblet cells.