Insecticidal potential of traditionally important plant, Zanthoxylum armatum DC (Rutaceae) against cabbage butterfly, Pieris brassicae (Linnaeus)

304-311Cabbage butterfly, Pieris brassicae (Linnaeus) is one of the most destructive pests of brassicaceous crops. Zanthoxylum armatum DC (Rutaceae) is versatile, traditionally important and edible medicinal plant, known to have insect repellent and larvicidal properties against many pests. Thus, the insecticidal potential of Z. armatum was evaluated against P. brassicae. N-hexane fraction of different plant parts of Z. armatum was extracted by using standard Soxhlet extraction method. Median lethal concentrations and time (LC50 and LT50) were determined by contact and oral toxicity tests by using Probit analysis. Pericarp and leaf extracts were found toxic to the caterpillars by contact. LC50’s of pericarp and leaf extract (by contact) was found to be 0.15% and 0.22%, respectively at 72 h. The relative toxicity of pericarp extract was recorded to be 1.50, when Azadirachtin 0.15 EC was considered as a unit. With sub-lethal concentrations, the developmental time was delayed; while percentage of pupation and adult emergence was significantly affected in treated caterpillars. In semi-field study, egg-laying of the female butterfly was significantly reduced and larval mortality was considerably higher (up to 53.33%) within 72 h after treatment in plants treated with Z. armatum extracts. In field trial, significant reduction (67.92%) in larval population was observed within 5 days of spraying of Z. armatum extracts

Not Available

Not AvailableSynonymous codons are randomly distributed among genes, a phenomenon termed as codon usage bias. Understanding the extent and pattern of codon bias; the forces affecting codon usage are the key steps towards elucidating the adaptive choice of codon at the level of individual genes. Herein, trends in codon usage bias in a set of 1450 genes in Salinibacter ruber, an extremely halophilic bacterium have been evaluated. Notably, synonymous codon usage varies considerably among genes of this bacterium. Base composition (mutational bias) particularly Cand G-ending codons predominate with greater preference of ‘C’ at synonymously variable sites. The effect of natural selection acting at the level of translation has been observed. Certain genes with a high codon bias have been identified by multivariate statistical approach and investigations through various codon bias indices. These genes appear to be highly expressed, and their codon usage seems to have been shaped by selection favouring a limited number of translationally optimal codons. A subset of 27 optimal codons seems to be preferentially used in highly expressed genes. The frequency of these codons appears to be correlated with the level of gene expression, and may be a useful indicator in the case of genes (or open reading frames) whose expression levels are unknown.Not Availabl

Not Available

Not AvailableSanjukta RK, Farooqi MS, Sharma N, Rai N, Mishra DC, Rai A, Singh DP, Chaturvedi KK., Statistical Analysis of codon usage in extremely halophilic bacterium, Salinibacter ruber DSM 13855, Online J Bioinform., 14(1): 15-31, 2013. Synonymous codons are randomly distributed among genes, a phenomenon termed as codon usage bias. Understanding the extent and pattern of codon bias; the forces affecting codon usage are the key steps towards elucidating the adaptive choice of codon at the level of individual genes. Herein, trends in codon usage bias in a set of 1450 genes in Salinibacter ruber, an extremely halophilic bacterium have been evaluated. Notably, synonymous codon usage varies considerably among genes of this bacterium. Base composition (mutational bias) particularly C- and G-ending codons predominate with greater preference of ‘C’ at synonymously variable sites. The effect of natural selection acting at the level of translation has been observed. Certain genes with a high codon bias have been identified by multivariate statistical approach and investigations through various codon bias indices. These genes appearto be highly expressed, and their codon usage seems to have been shaped by selection favouring a limited number of translationally optimal codons. A subset of 27 optimal codons seems to be preferentially used in highly expressed genes. The frequency of these codons appears to be correlated with the level of gene expression, and may be a useful indicator in the case of genes (or open reading frames) whose expression levels are unknown.Not Availabl