Bacillus thuringiensis (Ishiwata, 1901; Berliner, 1915) has been extensively utilized as a microbial insecticide because it has potent insecticidal characteristics. A classification based on the H serotype of B. thuringiensis has been used for a long time. Some of the associations between H serotyping and insecticidal activity have come to be understood, while the correlations of H serotyping with specific DNA sequences have not been clarified. In this study, the correlations between H serotyping and the genome of B. thuringiensis were examined using a genome profiling (GP) method, which was a simple method of comparing two different genomes.
As a result of the phylogenetic analysis of B. thuringiensis by the GP method, all strains were clearly distinguished, and broadly divided into two groups. In addition, through comparing it with profiles of the same serotype in the H3 serotype it was shown that similar serotype strains shared some common species identification dots (Spiddos). Therefore, this study suggested not only differences between each strain but also similarities within the same H serotype strains.

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We have developed a fast and efficient PCR-based technique to sex all developmental stages of the ladybird beetle Harmonia axyridis. Previously, we established a male-specific fluorescent expressing strain of H. axyridis with the piggyBac vector. FISH analyses revealed that the transgene inserted into the H. axyridis genome in the male Y-chromosome. Because only males expressed the fluorescent signal, we were able to differentiate between the sexes of this transgenic strain even in newly hatched larvae. We took advantage of this insertion and designed an inverse PCR reaction and genome walking surrounding the inserted region to identify 3,781 bp of the male Y-chromosome genomic sequence. From this male specific region, we designed a PCR-based protocol to identify sexes from all H. axyridis developmental stages.

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Assam is well known for the production of golden-coloured silk from muga (Antheraea assama = assamensis) silkworm. Muga culture has a long tradition amongst the rural community of North-East India and the people of the district of Dhemaji in Assam are no exception in this regard. The process of culturing muga involves three successive phases, which are distinguished as pre-rearing, rearing and post rearing. The traditional rearers follow a variety of indigenous practices that were passed on from generation to generation by word of mouth. In recent years, however, these age-old, religiously followed and highly respected practices involving every step and stage of muga culture are often no longer adhered to by the younger generation of culturists. This disregard and/or ignorance of the traditional ways can compromise the quality of the muga silk product. The present study has been undertaken to record and publicize the traditions associated with muga rearing still being followed by the rural inhabitants of the Dhemaji district of Assam.

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