Determination of malathion and diazinon resistance by sequencing the Md alpha E7 gene from Guatemala, Colombia, Manhattan, and Thailand housefly (Musca domestica L.) strains

Organophosphate (OP) insecticides (parathion/diazinon) resistance in housefly (Musca domestica L.) is associated with the change in carboxylesterase activity. The product of alphaE7 gene, which is a member of alpha-esterase gene cluster, is probably playing a role in detoxyfication of the xenobiotic esters. In parathion/diazinon resistant M. domestica species Gly(137) to Asp substitution was found in the active center of the product of alphaE7 gene. In malathion (an OP) resistant M. domestica strains Trp(251) to Ser substitution was identified in the active center of the MdalphaE7. In our research, to understand the allelic diversity of the MdalphaE7, the gene was partially sequenced from four different housefly strains from different localities (Guatemala, Manhattan (USA), Colombia (USA), and Thailand). It was found out that; in Thailand strain one allele has Cys residue at the position of 251, the other allele contains a Trp for the same site. In Colombia strain, one allele has Asp(137), the other allele contains a Gly residue at this point. The Manhattan and Guatemala strains have Asp(137) and Trp(251) residues on their both alleles at these two different positions

Development of Random Amplified Polymorphic DNA (RAPD) markers in 150 F-6-inbred durum wheat (Triticum durum) lines derived from Kunduru-1149 x Cham-1 cross

Random Amplified Polymorphic DNA (RAPD) markers were developed in a specific durum wheat population (150 lines) derived from Kunduru-1149 x Chain-1 cross. Of 284 RAPD primers screened against parent DNAs, 83 revealed at least one polymorphic locus. The most polymorphic and clear bands producing 13 primers were selected and screened with the DNAs of 150 lines. These 13 primers revealed a total number of 33 segregating loci. The preliminary results of this study could be used as a base for mapping economically important character loci of durum wheat by the development of other RAPDs

Response of 150 F6 inbred durum wheat lines derived from Kunduru-1149×Cham-1 cross to yellow rust (Puccinia striiformis)

One hundred and fifty F6 inbred durum wheat lines derived from Kunduru-1149 x Cham-1 cross were characterised in terms of their response to yellow rust (Puccinia striiformis) race population including Yr2, Yr6, Yr7 and Yr9 virulence genes. The results revealed that there is a considerable amount of genetic variation among these lines and yellow rust resistance in durum wheat is highly heritable (92%). Twenty-five of 150 lines (16.67%) were found totally immune, 104 of them (69.33%) were found to be resistant or moderately resistant while only 21 of them (14%) were found to be susceptible. Hence, 86% of the lines tested in this study could be used as a source of yellow rust resistance in breeding programmes