Asiatic cotton (Gossypium arboreum L.) cultivars, possessing short staple length, superior water ... more Asiatic cotton (Gossypium arboreum L.) cultivars, possessing short staple length, superior water holding capacity and high micronaire values are considered fit for manufacturing absorbent cotton. Such cultivars are cultivated in north and northeast India. Field studies were conducted at the experimental farm of the ICAR-Central Institute for Cotton Research, Nagpur, from 2013–14 to 2015–16, to evaluate productivity and fibre properties of Asiatic cotton cultivars from north (race bengalense) and northeast (race cernuum) India vis-à -vis the cultivars of central and south India (race indicum). In 2013, RG8 produced the highest seed cotton yield (1759 kg/ha), but did not differ from Phule Dhanwantary (1599 kg/ha) and BG-II hybrid H6 (1518 kg/ha). Averaged over 2014–15 and 2015–16, AKA8, CNA418, CNA375, CNA423, Phule Dhanwantary and MDLABB (1489 to 1989 kg/ha) gave significantly higher seed cotton yield than BGII hybrid Mallika (953 kg/ha). In general, cultivars from north and ...
Zenodo (CERN European Organization for Nuclear Research), 2012
A location specific Insecticide Resistance Management (IRM) strategies module developed for pest ... more A location specific Insecticide Resistance Management (IRM) strategies module developed for pest management in Bt and Non Bt cotton was implemented and evaluated in cotton (Gossypium hirsutum) growing villages of Haryana .Large scale field evaluation of the technology indicated the reduction in number of insecticidal sprays (30.65%, 24.29% in 2007-08 and 2008-09, respectively) and shift in pesticide use pattern in adopted villages. Though the populations of sucking pests were not significantly different in IRM and Non IRM fields but total consumption of insecticides was 26.79% and 31.24% higher during 2007-08 and 2008-09, respectively in Non-IRM over IRM villages. Moreover, IRM adopted villages of Sirsa, Fatehabad and Hisar harboured higher number of natural enemies as compared to non IRM villages. The yield was found significantly higher in fields where IRM strategies were adopted (21.60 and 23.79 q/ha) over field that adopted farmers practices (i e non IRM) (20.74 and 21.61 q/ha) during 2007-08 and 2008-09.
Background: Helicoverpa armigera and H. zea are amongst the most significant polyphagous pest lep... more Background: Helicoverpa armigera and H. zea are amongst the most significant polyphagous pest lepidopteran species in the Old and New Worlds respectively. Separation of H. armigera and H. zea is difficult and is usually only achieved through morphological differences in the genitalia. They are capable of interbreeding to produce fertile offspring. The single species status of H. armigera has been doubted, due to its wide distribution and plant host range across the Old World. This study explores the global genetic diversity of H. armigera and its evolutionary relationship to H zea. Results: We obtained partial (511 bp) mitochondrial DNA (mtDNA) Cytochrome Oxidase-I (COI) sequences for 249 individuals of H. armigera sampled from Australia, Burkina Faso, Uganda, China, India and Pakistan which were associated with various host plants. Single nucleotide polymorphisms (SNPs) within the partial COI gene differentiated H. armigera populations into 33 mtDNA haplotypes. Shared haplotypes between continents, low F-statistic values and low nucleotide diversity between countries (0.0017-0.0038) suggests high mobility in this pest. Phylogenetic analysis of four major Helicoverpa pest species indicates that H. punctigera is basal to H. assulta, which is in turn basal to H. armigera and H. zea. Samples from North and South America suggest that H. zea is also a single species across its distribution. Our data reveal short genetic distances between H. armigera and H. zea which seem to have been established via a founder event from H. armigera stock at around 1.5 million years ago. Conclusion: Our mitochondrial DNA sequence data supports the single species status of H. armigera across Africa, Asia and Australia. The evidence for inter-continental gene flow observed in this study is consistent with published evidence of the capacity of this species to migrate over long distances. The finding of high genetic similarity between Old World H. armigera and New World H. zea emphasises the need to consider work on both pests when building pest management strategies for either.
Cotton leaf curl virus is a devastating pest in the North India and in small pockets of Southern ... more Cotton leaf curl virus is a devastating pest in the North India and in small pockets of Southern states. Cotton leaf curl disease (CLCuD) is caused by a Geminivirus, transmitted by whitefly Bemisia tabaci vector. This is a serious problem in the northern region and leads to yield losses up to 58% and 69% (ICAC recorder, 1999). Genetic engineering for cotton transgenics resistant to leaf curl disease (CLCuD) through antisense RNA approach is potential to tackle the disease in cotton. Cotton transgenics resistant to leaf curl disease (CLCuD) using Antisense (rep) (Replicase protein) gene was developed via Agrobacterium mediated transformation. A binary vector carrying the Antisense rep gene along with the npt II (neomycin phospho transferase) gene driven by CaMV-35S promoter and NOS (nopaline synthase) terminator was used for transformation. The confirmation of the rep and npt II genes in the transgenic plants were verified by PCR and integration of T-DNA into the plant genome was con...
Pyrethroid, organophosphate, carbamate and cyclodiene resistance levels for the cotton bollworm (... more Pyrethroid, organophosphate, carbamate and cyclodiene resistance levels for the cotton bollworm (Helicoverpa armigera) have been monitored routinely at sites throughout India since 1993 using discriminating dose assays. Resistance by H. armigera and other pests to commonly used insecticides is a severe constraint to cotton production in India. An integrated crop management strategy was developed aimed at maximising profit while minimising insecticide use and the impact of insecticide resistance. Appropriate varieties and agronomy, plus seed treatment where necessary, allow the first foliar insecticides to be delayed until at least 70 days from planting. Insecticides for fruit and leaf feeders are then rotated, taking account of seasonal shifts in their efficacy and the pest spectrum faced; with endosulfan first, followed by particular organophosphates, leaving one to two pyrethroid sprays until the late season when pink bollworm is also present. This system (customised for the diffe...
Cotton seed based artificial diet has been standardized for continuous rearing of pink bollworm P... more Cotton seed based artificial diet has been standardized for continuous rearing of pink bollworm Pectinophora gossypiella (Saunders) at the Central Institute for Cotton Research, Regional Station, Coimbatore. The ingredients of the diet are easily available and are cost effective. Basic ingredients of the diet are cotton seed flour (processed) and chick pea flour, Carbohydrate, Protein, Fat sources, multi vitamin, antimicrobial agents and agar as thickening agent are used as other ingredients. Micro centrifuge tubes with lid were used as rearing containers. Individual neonate larvae were released on each piece of the diet inside the micro centrifuge tube and the lids were closed. This prevented larval escape, retaining them inside the tubes and also prevented diet dehydration. The recovery of insect reared on diet was recorded as 95.56%. Egg hatchability and adult emergence were 100% while pupal malformation was nil. Eggs, larval and pupal periods were recorded as 4.8 ± 0.632, 25.10 ± 0.994 and 7.9 ± 0.88 days, respectively. Larval and pupal weights were recorded as 21.40 mg ± 3.63, 18.00 mg ± 2.73, respectively.
India, Pakistan and China produce over 50% of the world's cotton. About 44% of the cost of produc... more India, Pakistan and China produce over 50% of the world's cotton. About 44% of the cost of production (US $1500M annum) is accounted for by the purchase of insecticides mainly for the control of cotton bollworms Helicoverpa armigera. Resistance by Helicoverpa armigera to commonly used insecticides is severe constrain to cotton production in these countries. It also results in escalation of pest control measures across the region and causes significant environmental and human health problems. Under the Collaborative, (CFC/ ICAC/ 14
The mode of inheritance of resistance to Cry1Ac toxin of Bacillus thuringiensis in the cotton bol... more The mode of inheritance of resistance to Cry1Ac toxin of Bacillus thuringiensis in the cotton bollworm, Helicoverpa armigera (Hu¨bner), was elucidated through bioassay analysis of the response of resistant, susceptible, F 1 hybrid and backcross H. armigera progeny to Cry1Ac using semi-synthetic diet and transgenic Bt cotton plants. The dominance value estimates ranged between 0.42 and 0.57. Resistance was found to be monogenic, autosomal and inherited as a semi-dominant trait. Genetic studies of response of H. armigera to transgenic Bt cotton showed that the effective resistance on transgenic Bt cotton plants was also inherited as a semidominant trait.
Archives Of Phytopathology And Plant Protection, 2012
Cotton leaf curl disease (CLCuD) is caused by begomovirus, transmitted by whitefly Bemisia tabaci... more Cotton leaf curl disease (CLCuD) is caused by begomovirus, transmitted by whitefly Bemisia tabaci vector is a serious pest in North India. Cotton leaf Curl Virus Disease is one of the major threats for cotton production and has emerged as serious disease of cotton in North India. Genetic engineering of cotton transgenics resistant to CLCuD through antisense RNA approach is
The quantitative levels of Cry1Ac and the seasonal decline in expression differed significantly a... more The quantitative levels of Cry1Ac and the seasonal decline in expression differed significantly among the eight commercial Bollgard hybrids tested. The Cry1Ac expression was found to be variable among the hybrids and also between different plant parts. The leaves of Bt-cotton plants were found to have the highest levels of Cry1Ac expression followed by squares, bolls and flowers. The toxin expression in the boll-rind, square bud and ovary of flowers was clearly inadequate to confer full protection to the fruiting parts. Increasing levels of Helicoverpa armigera survival were correlated with the toxin levels decreasing below 1.8 µ µg/g in the plant parts. Genotype-independent seasonal decline of the Cry1Ac toxin levels was observed in all the hybrids. Cry1Ac expression decreased consistently as the plant aged. The decline in Cry1Ac was more rapid in some hybrids compared to others. The choice of parental background appeared to be crucial for sustainable expression of the cry1Ac transgene. The implications of variability in Cry1Ac expression and the seasonal decline on bollworm management are discussed.
Asiatic cotton (Gossypium arboreum L.) cultivars, possessing short staple length, superior water ... more Asiatic cotton (Gossypium arboreum L.) cultivars, possessing short staple length, superior water holding capacity and high micronaire values are considered fit for manufacturing absorbent cotton. Such cultivars are cultivated in north and northeast India. Field studies were conducted at the experimental farm of the ICAR-Central Institute for Cotton Research, Nagpur, from 2013–14 to 2015–16, to evaluate productivity and fibre properties of Asiatic cotton cultivars from north (race bengalense) and northeast (race cernuum) India vis-à -vis the cultivars of central and south India (race indicum). In 2013, RG8 produced the highest seed cotton yield (1759 kg/ha), but did not differ from Phule Dhanwantary (1599 kg/ha) and BG-II hybrid H6 (1518 kg/ha). Averaged over 2014–15 and 2015–16, AKA8, CNA418, CNA375, CNA423, Phule Dhanwantary and MDLABB (1489 to 1989 kg/ha) gave significantly higher seed cotton yield than BGII hybrid Mallika (953 kg/ha). In general, cultivars from north and ...
Zenodo (CERN European Organization for Nuclear Research), 2012
A location specific Insecticide Resistance Management (IRM) strategies module developed for pest ... more A location specific Insecticide Resistance Management (IRM) strategies module developed for pest management in Bt and Non Bt cotton was implemented and evaluated in cotton (Gossypium hirsutum) growing villages of Haryana .Large scale field evaluation of the technology indicated the reduction in number of insecticidal sprays (30.65%, 24.29% in 2007-08 and 2008-09, respectively) and shift in pesticide use pattern in adopted villages. Though the populations of sucking pests were not significantly different in IRM and Non IRM fields but total consumption of insecticides was 26.79% and 31.24% higher during 2007-08 and 2008-09, respectively in Non-IRM over IRM villages. Moreover, IRM adopted villages of Sirsa, Fatehabad and Hisar harboured higher number of natural enemies as compared to non IRM villages. The yield was found significantly higher in fields where IRM strategies were adopted (21.60 and 23.79 q/ha) over field that adopted farmers practices (i e non IRM) (20.74 and 21.61 q/ha) during 2007-08 and 2008-09.
Background: Helicoverpa armigera and H. zea are amongst the most significant polyphagous pest lep... more Background: Helicoverpa armigera and H. zea are amongst the most significant polyphagous pest lepidopteran species in the Old and New Worlds respectively. Separation of H. armigera and H. zea is difficult and is usually only achieved through morphological differences in the genitalia. They are capable of interbreeding to produce fertile offspring. The single species status of H. armigera has been doubted, due to its wide distribution and plant host range across the Old World. This study explores the global genetic diversity of H. armigera and its evolutionary relationship to H zea. Results: We obtained partial (511 bp) mitochondrial DNA (mtDNA) Cytochrome Oxidase-I (COI) sequences for 249 individuals of H. armigera sampled from Australia, Burkina Faso, Uganda, China, India and Pakistan which were associated with various host plants. Single nucleotide polymorphisms (SNPs) within the partial COI gene differentiated H. armigera populations into 33 mtDNA haplotypes. Shared haplotypes between continents, low F-statistic values and low nucleotide diversity between countries (0.0017-0.0038) suggests high mobility in this pest. Phylogenetic analysis of four major Helicoverpa pest species indicates that H. punctigera is basal to H. assulta, which is in turn basal to H. armigera and H. zea. Samples from North and South America suggest that H. zea is also a single species across its distribution. Our data reveal short genetic distances between H. armigera and H. zea which seem to have been established via a founder event from H. armigera stock at around 1.5 million years ago. Conclusion: Our mitochondrial DNA sequence data supports the single species status of H. armigera across Africa, Asia and Australia. The evidence for inter-continental gene flow observed in this study is consistent with published evidence of the capacity of this species to migrate over long distances. The finding of high genetic similarity between Old World H. armigera and New World H. zea emphasises the need to consider work on both pests when building pest management strategies for either.
Cotton leaf curl virus is a devastating pest in the North India and in small pockets of Southern ... more Cotton leaf curl virus is a devastating pest in the North India and in small pockets of Southern states. Cotton leaf curl disease (CLCuD) is caused by a Geminivirus, transmitted by whitefly Bemisia tabaci vector. This is a serious problem in the northern region and leads to yield losses up to 58% and 69% (ICAC recorder, 1999). Genetic engineering for cotton transgenics resistant to leaf curl disease (CLCuD) through antisense RNA approach is potential to tackle the disease in cotton. Cotton transgenics resistant to leaf curl disease (CLCuD) using Antisense (rep) (Replicase protein) gene was developed via Agrobacterium mediated transformation. A binary vector carrying the Antisense rep gene along with the npt II (neomycin phospho transferase) gene driven by CaMV-35S promoter and NOS (nopaline synthase) terminator was used for transformation. The confirmation of the rep and npt II genes in the transgenic plants were verified by PCR and integration of T-DNA into the plant genome was con...
Pyrethroid, organophosphate, carbamate and cyclodiene resistance levels for the cotton bollworm (... more Pyrethroid, organophosphate, carbamate and cyclodiene resistance levels for the cotton bollworm (Helicoverpa armigera) have been monitored routinely at sites throughout India since 1993 using discriminating dose assays. Resistance by H. armigera and other pests to commonly used insecticides is a severe constraint to cotton production in India. An integrated crop management strategy was developed aimed at maximising profit while minimising insecticide use and the impact of insecticide resistance. Appropriate varieties and agronomy, plus seed treatment where necessary, allow the first foliar insecticides to be delayed until at least 70 days from planting. Insecticides for fruit and leaf feeders are then rotated, taking account of seasonal shifts in their efficacy and the pest spectrum faced; with endosulfan first, followed by particular organophosphates, leaving one to two pyrethroid sprays until the late season when pink bollworm is also present. This system (customised for the diffe...
Cotton seed based artificial diet has been standardized for continuous rearing of pink bollworm P... more Cotton seed based artificial diet has been standardized for continuous rearing of pink bollworm Pectinophora gossypiella (Saunders) at the Central Institute for Cotton Research, Regional Station, Coimbatore. The ingredients of the diet are easily available and are cost effective. Basic ingredients of the diet are cotton seed flour (processed) and chick pea flour, Carbohydrate, Protein, Fat sources, multi vitamin, antimicrobial agents and agar as thickening agent are used as other ingredients. Micro centrifuge tubes with lid were used as rearing containers. Individual neonate larvae were released on each piece of the diet inside the micro centrifuge tube and the lids were closed. This prevented larval escape, retaining them inside the tubes and also prevented diet dehydration. The recovery of insect reared on diet was recorded as 95.56%. Egg hatchability and adult emergence were 100% while pupal malformation was nil. Eggs, larval and pupal periods were recorded as 4.8 ± 0.632, 25.10 ± 0.994 and 7.9 ± 0.88 days, respectively. Larval and pupal weights were recorded as 21.40 mg ± 3.63, 18.00 mg ± 2.73, respectively.
India, Pakistan and China produce over 50% of the world's cotton. About 44% of the cost of produc... more India, Pakistan and China produce over 50% of the world's cotton. About 44% of the cost of production (US $1500M annum) is accounted for by the purchase of insecticides mainly for the control of cotton bollworms Helicoverpa armigera. Resistance by Helicoverpa armigera to commonly used insecticides is severe constrain to cotton production in these countries. It also results in escalation of pest control measures across the region and causes significant environmental and human health problems. Under the Collaborative, (CFC/ ICAC/ 14
The mode of inheritance of resistance to Cry1Ac toxin of Bacillus thuringiensis in the cotton bol... more The mode of inheritance of resistance to Cry1Ac toxin of Bacillus thuringiensis in the cotton bollworm, Helicoverpa armigera (Hu¨bner), was elucidated through bioassay analysis of the response of resistant, susceptible, F 1 hybrid and backcross H. armigera progeny to Cry1Ac using semi-synthetic diet and transgenic Bt cotton plants. The dominance value estimates ranged between 0.42 and 0.57. Resistance was found to be monogenic, autosomal and inherited as a semi-dominant trait. Genetic studies of response of H. armigera to transgenic Bt cotton showed that the effective resistance on transgenic Bt cotton plants was also inherited as a semidominant trait.
Archives Of Phytopathology And Plant Protection, 2012
Cotton leaf curl disease (CLCuD) is caused by begomovirus, transmitted by whitefly Bemisia tabaci... more Cotton leaf curl disease (CLCuD) is caused by begomovirus, transmitted by whitefly Bemisia tabaci vector is a serious pest in North India. Cotton leaf Curl Virus Disease is one of the major threats for cotton production and has emerged as serious disease of cotton in North India. Genetic engineering of cotton transgenics resistant to CLCuD through antisense RNA approach is
The quantitative levels of Cry1Ac and the seasonal decline in expression differed significantly a... more The quantitative levels of Cry1Ac and the seasonal decline in expression differed significantly among the eight commercial Bollgard hybrids tested. The Cry1Ac expression was found to be variable among the hybrids and also between different plant parts. The leaves of Bt-cotton plants were found to have the highest levels of Cry1Ac expression followed by squares, bolls and flowers. The toxin expression in the boll-rind, square bud and ovary of flowers was clearly inadequate to confer full protection to the fruiting parts. Increasing levels of Helicoverpa armigera survival were correlated with the toxin levels decreasing below 1.8 µ µg/g in the plant parts. Genotype-independent seasonal decline of the Cry1Ac toxin levels was observed in all the hybrids. Cry1Ac expression decreased consistently as the plant aged. The decline in Cry1Ac was more rapid in some hybrids compared to others. The choice of parental background appeared to be crucial for sustainable expression of the cry1Ac transgene. The implications of variability in Cry1Ac expression and the seasonal decline on bollworm management are discussed.
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