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Not AvailablePink mealybug Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae) is a destructive pest of agricultural and horticultural crops. Insecticides are the major tool used to control M. hirsutus. The present study was conducted to evaluate resistance to the commonly used insecticides acephate, dichlorvos, imidacloprid and buprofezin in M. hirsutus collected from seven different geographical locations of mulberry and vineyards in India. Detoxifying enzymes, namely esterase, glutathione S transferase (GST) and cytochrome P-450 (cyt-P450), were quantified in populations. One population from Erode showed a low level of resistance to acephate (resistance ratio [RR] 10.3-fold), one from Salem showed a low level of resistance to dichlorvos (resistance ratio [RR] 13.7-fold), one from Sangli showed a very low level of resistance to imidacloprid (RR 10.2-fold), and one from Chikkaballapur showed a low level of resistance to buprofezin (RR 14.8-fold). Activity ratios for detoxifying enzymes ranged from 1.8- to 4.9-fold for GST, 1.8- to 3.7-fold for esterase and 1.9- to 2.4-fold for cyt-P450. Furthermore, organophosphate resistance and activity of enzymes (esterase, GST and cyt-P450) were positively correlated. To contain the evolution of resistance to M. hirsutus infestation, buprofezin and imidacloprid could be used, supplemented with biointensive integrated management strategies and regular resistance monitoring programs.Not Availabl

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Not AvailableDNA barcoding has been widely used in species identification and biodiversity research because it has been shown that in many groups, including insects, interspecific variation in DNA sequences of some genes is much higher than intraspecific and this provided an opportunity to use DNA sequences for species identification. Cytochrome oxidase I (COI) barcoding sequences can be used to discover cryptic, closely related and morphologically similar species. DNA barcoding has gained increased recognition as a molecular tool for species identification in various groups of organisms. A study was, therefore, undertaken to barcode five fly species prevalent in poultry farms in and around Bengaluru districts in Karnataka state. The barcoding of COI gene of Musca domestica, Chrysomya megacephala, Hydrotaea capensis, Hermetia illucens and Sarcophaga ruficornis yielded an amplified fragment of 658 bp sequence. Barcode for all 5 species was generated using Bold_Systems v3 and submitted to GenBank and accession numbers were obtained. In the present study, identification of five different fly species based on morphology was also confirmed by DNA barcoding to prove their correct identity.Not Availabl

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Not AvailableThe whole genome of Helicoverpa armigera nucleopolyhedrovirus (HearNPV) from India, HearNPV-L1, was sequenced and analyzed, with a view to look for genes and/or nucleotide sequences that might be involved in the differences and virulence among other HearNPVs sequenced from other countries like SP1A (Spain), NNg1 (Kenya) and G4 (China). The entire nucleotide sequence of the HearNPV-L1 genome was 136,740 bp in length having GC content of 39.19% and contained 113 ORFs that could encode polypeptides with more than 50 amino acids (GenBank accession number KT013224). Two ORFs, viz., ORF 18 (300 bp) and ORF 19 (401 bp) identified were unique in HearNPV-L1 genome. Most of the HearNPV-L1 ORFs showed high similarity to NNg1, SP1A and G4 genomes. HearNPV-L1 genome contains 5 h (hr1-hr5), these regions were found 84–100% similar to hr region of NNg1, SP1A and G4 genomes. A total of four bro genes were observed in HearNPV-L1 genome, of which bro-a gene was 12 and 351 bp bigger than SP1A and G4 bro-a, respectively, while bro-b was 15 bp bigger SP1A and NNg1 bro-b, whereas 593 bp shorter than G4 bro-b, while bro-c was 12 bp shorter than NNg1, however bro-c was absent in G4 genome. HearNPV-L1 bro-d was 100% homologous to bro-d of SP1A, NNg1 and G4 genomes, respectively. The comparative analysis of HearNPV-L1 genome indicated that there are several other putative genes and nucleotide sequences that may be responsible for insecticidal activity in HearNPV-L1 isolate, however, further functional analysis of the hypothetical (putative) genes may help identifying the genes that are crucial for the virulence and insecticidal activityNot Availabl

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Not AvailableInheritance of monocrotophos resistance was studied in the laboratory population of T. chilonis. After 10 cycles of selection pressure under laboratory condition, the resistant strain acquired LC50 value of 0.346mL compared toLC50 value of 0.114 mL in the susceptible strain. Evidence from bioassay of F1 reciprocal hybrid crosses backcrossed with respective resistant 'R' and susceptible 'S'parentalstrains of T. chilonis, aimed to determine mode of inheritance of insecticide tolerance indicated that F1 crosses exhibited a complete dominant response to monocrotophos, with degree of dominance value (D) of 1.62. The resistance factor (Rf) of resistant strain was 3.04 folds and of F1 crosses were 3.675 folds over susceptible strain. Result of this study suggests resistance to the insecticide was probably controlled by a single gene. These results provide the basic information for designing successful management programmes for the control of Lepidopteran pests using resistant strain as a component of IPM.Not Availabl

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Not AvailableNearly 5 000 aphid species damage crops, either by sucking plant sap or as disease-transmitting vectors. Microsatellites are used for understanding molecular diversity and eco-geographical relationships among aphid species. Expressed sequence tag (EST)-microsatellite motifs were identified through an in silico approach using inbuilt simple sequence repeat mining tools in aphid EST dataset. Microsatellite mining revealed one in every five aphid genes as containing a repeat motif, and out of 9 290 EST microsatellites mined from Aphis gossypii Glover and Acyrthosiphon pisum (Harris) (both Hemiptera: Aphididae), 80% were of A and/or T (AT, ATA, AAT, AATA, and ATTT) motifs, and the rest contained G and/or C motifs. All microsatellite sequences were annotated using BLAST. Primers for EST microsatellites were designed using the Primer 3.0 tool. 106 primer pairs of both dinucleotide repeats (DNRs) and trinucleotide repeats (TNRs), representing open reading frames (ORFs) and untranslated regions (UTRs), were synthesized to amplify 15 aphid species belonging to the subfamily Aphidinae, collected from diverse hosts. Four hundred forty-five polymorphic alleles were amplified. Fifty TNR and 23 DNR microsatellites amplified across the species studied. Polymorphism information content values of microsatellites ranged from 0.23 to 0.91, amplifying 2–16 alleles.Genetic similarity indices were estimated using the ‘NTSYS-pc’ software package. Unweighted pair group with arithmetic mean and principal component analysis resolved taxonomic relationships of the aphid species studied. The new aphid microsatellites developed will provide valuable information to researchers to study Indian aphid species diversity and genetic relationships.Not Availabl

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Not AvailableAmong the major pests of maize in India are two stem borers, Chilo partellus (Swinhoe) and Sesamia inferens (Walker), and an earworm, Helicoverpa armigera (Hübner). As a pest control strategy, transgenic Bacillus thuringiensis (Bt) maize hybrids are undergoing regulatory trials in India. We have determined the sensitivity of the target lepidopterans to the insecticidal Bt proteins expressed in Bt maize, as this determines product efficacy and the resistance management strategy to be adopted. Maize hybrids with event MON89034 express two insecticidal Bt proteins, Cry1A.105 and Cry2Ab2.Not Availabl

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Not AvailableCotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), is a serious pest of several crops throughout the world, representing millions of United States of America dollars worth of damage. This pest can adapt to various cropping systems in a wide geographical range and has high migratory potential. It features high fecundity and can develop resistance to almost all insecticides used for its management. Several investigations to develop microsatellite markers for H. armigera have not been successful because of the paucity of microsatellites in the lepidopteran genome. As well, collections of H. armigera from cotton fields of southern and western India were not yet studied for molecular genetic diversity. The current study aimed to screen publicly available expressed sequence tag resources for simple sequence repeats and assess their potential as DNA markers for assessment of gene flow between collections of southern and western India. We identified 30 polymorphic microsatellites for potential use in diversity analysis of H. armigera collections. Genetic diversity analysis revealed that the collections were widely diverse with population differentiation index (Fst) of 0.17. Furthermore, gene flow analysis revealed a mean frequency of private alleles of 11% within the collections. The microsatellite resources we developed could be widely used for molecular diversity or population genetic research involving this important pest of cotton and food crops.Not Availabl