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Journal Cover Proceedings of the Zoological Society
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   Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 0974-6919 - ISSN (Online) 0373-5893
     Published by Springer-Verlag Homepage  [2209 journals]
  • Stimulation of Murine Immune Response by the Tubers of        class="a-plus-plus">Dioscorea alata L. of
           North-Eastern Region of India
    • Abstract: Abstract Dioscorea alata is a staple food in south-eastern Asia and Africa and also widely consumed in the North-eastern region of India. Its medicinal value is well established, but the immunomodulatory property has never been studied on animal model. Therefore, we have investigated the immunomodulatory activity of D. alata by performing plaque forming cell assay, haemagglutination titer, stimulation of phagocytosis assay, inhibition of lipopolysaccharide (LPS) induced nitric oxide (NO) synthesis, carbon-clearance test, in vitro cell adhesions assay and various cell counts. Effect of D. alata on various organ weight and total serum protein, albumin and globulin levels were also determined. At 100 mg/kg dose the macrophages were highly stimulated (P < 0.001) to proliferate and the plaque forming cell number was also found to be optimum (P < 0.001) at the same dose. Elimination of foreign material from the system was found to be highest at 250 mg/kg dose. Both at 100 and 250 mg/kg doses, the phagocytic activity of the macrophages was increased significantly (P < 0.001). Anti-inflammatory activity of D. alata was proved by the inhibition of LPS induced NO synthesis by macrophages. Therefore, it can be concluded that 70 % hydro-methanolic extract of D. alata has profound immunostimulating potential in the murine model, stimulating both humoral and innate arms of the immune system.
      PubDate: 2014-12-01
       
  • Factors Affecting Distribution of Earthworms in Kashmir Valley: A
           Multivariate Statistical Approach
    • Abstract: Abstract Soil characteristics influence earthworm population dynamics, species distribution and community structure. According in the present study an attempt was made to determine the soil physiochemical factors influencing earthworms of Kashmir valley with a view to improve the soil productivity by enhancing earthworm diversity under different pedoecosystems. Data collection on 15 soil parameters from 20 earthworm inhabiting sites revealed significant variation within and among the sites in soil temperature (F23, 19 = 148.83, 9.71; P < 0.05), moisture (F23, 19 = 16.91, 46.20; P < 0.05), pH (F19 = 47.21; P < 0.05), electrical conductivity (F23, 19 = 11.67, 87.13; P < 0.05), sodium (F23, 19 = 2.46, 211.25; P < 0.05), potassium (F19 = 22.91; P < 0.05), calcium (F19 = 15.90; P < 0.05), magnesium (F23, 19 = 1.76, 104.51; P < 0.05), organic carbon (F23, 19 = 64.60, 222.50; P < 0.05), organic nitrogen (F23, 19 = 4.59, 3.81; P < 0.05) and phosphorous (F23, 19 = 5.11, 137.87; P < 0.05). Aporrectodea caliginosa trapezoides and A. rosea rosea exhibited wide range of distribution whereas Octolasion cyaneum, A. c. trapezoides and A. parva showed restricted distribution. Hierarchical cluster analysis grouped 20 earthworm collection sites into three clusters—earthworm absent sites, low earthworm diversity sites and moderate earthworm diversity sites. Principal component analysis assisted from the data set of 20 sites, resulting into four latent factors accounting for 77.95 % of total variance, identified the factors affecting earthworm communities are mainly related to physical habitat factor, chemical factor, soil texture factor and growth factor, each accounting for 26.41, 20.16, 18.25 and 13.13 % of total variance respectively.
      PubDate: 2014-12-01
       
  • Habitat Attributes and Waterbird-Use of Four Wetlands in Manas National
           Park, Assam, India
    • Abstract: Abstract We studied the relationship between habitat characteristics and the use of wetlands by the waterbirds over 5 years in Manas National Park, Assam. Patterns of temporal and spatial variation in waterbird diversity, abundance and community composition were quantified in relation to eight wetland attributes. There were significant declines in majority of the waterbird species during the course of this study; carnivorous and omnivorous birds being the major sufferers. The waterbird communities exhibited both spatial and temporal shifts in distribution and community composition along with the shifts in their major food resources, and primary productivity of the wetlands did not appear to play a major role in these shifts. Our study also demonstrates that the observed declines in waterbird abundances were associated with declines in zooplankton and macroinvertebrate densities. Temporal changes in wetland size also played some roles in the waterbird decline and community composition.
      PubDate: 2014-12-01
       
  • Pathological Changes in Mermithid Nematode Infected        class="a-plus-plus">Stictochironomus polystictus
           (Kieffer) (Diptera, Chironomidae, Chironominae)
    • Abstract: Abstract Mermithid nematodes cause morphological and sexual anomalies in the pupae and adults of Stictochironomus polystictus (Kieffer). The parasite-induced changes resulted in the development of three types of intersexes. Structural alterations of adult males were variation of antennal length, appearance of antenna and number of flagellomeres, VIIIth abdominal segment, genitalia and associated appendages while in pupae, the length of antennal sheath and genital sac. However, the midge larvae infected with nematodes did not show any abnormality in morphological features. These entomopathogenic worms infecting male chironomids can feminize them and induce them to adopt a female behavior and return to water. So the worms apparently benefit from behavioral changes of the infected host, thereby reaching their abode where new hosts for its juveniles may be encountered. Since parasitized insects are usually castrated by worms before the beginning of the morphological changes, the behavioral alterations do not make additional fitness to the host.
      PubDate: 2014-12-01
       
  • Visceral Dracunculiasis: A Case Report from East Medinipore District, West
           Bengal, India
    • Abstract: A case of visceral dracunculiasis in a female patient is reported from east Medinipur district, West Bengal, India. It is the first report from the eastern India. The patient from rural West Bengal underwent laparoscopic cholecystectomy on 13th March 2002 and after 3 days the patient was released with a drain in the upper abdomen because of persistence of fluid of about 50 ml per day. The patient was to readmit after 8 days with a history of expulsion of one worm through the drain tube and next day another four living worms were expelled through the tube. Subsequently the drain dried up and the patient was released after removing the tube. The worms are identified as Dracunculus medinensis, possibly remaining within the abscess developing adjacent to the gall bladder and it is a case of visceral dracunculiasis reported first time from eastern India.
      PubDate: 2014-12-01
       
  • Evaluation of Acute Toxicity Levels and Ethological Responses Under
           Tetrachlorocatechol Exposure in Common Carp,        class="a-plus-plus">Cyprinus carpio (Linnaeus)
    • Abstract: Tetrachlorocatechol (TCC) is one of the most toxic chlorinated catechol produced by the chlorobleaching of pulp and frequently found in the kraft pulp mill effluents. Toxicity of TCC to common carp, Cyprinus carpio and their ethological changes were evaluated in the present study. The 24, 48, 72 and 96 h LC50 values of TCC to C. carpio were 4.73, 3.95, 3.20 and 2.43 mg/l respectively. The mortality rate of C. carpio showed significant relationship (p < 0.05) at different exposure times (24, 48, 72 and 96 h) in different treatments of TCC (2, 3, 4, 5 and 7 mg/l). On the other hand, a significant correlation (p < 0.01) was observed between the mortality rate of fish with all the concentrations of TCC. Mean opercular movement in the fish increased significantly with the increasing dose and time of exposure to TCC indicating acute respiratory distress. The jerky movement, somersaulting, circular movement and mucus secretion of fish increased gradually with the increasing concentrations and exposure times of TCC for adapting a compensatory mechanism to derive energy in order to avoid stress due to toxicity.
      PubDate: 2014-12-01
       
  • Post Bleaching Assessment of Corals in Andaman and Nicobar Islands
    • Abstract: Reefs of Andaman and Nicobar Islands harbour 418 species of scleractinian corals spread over an area of 2,000 km2. In April to May, 2010, due to the delayed onset of the southwest monsoon the sea surface temperature of the coastal and oceanic region increased to 31.7 °C in respect to the earlier record of maximum 29.0 °C during the said period. This resulted in mass bleaching of hermatypic corals during May, 2010. Rapid under water surveys have been conducted in reefs of Andaman and Nicobar Islands to assess the health of corals between May 2010 and August 2011. It is estimated that 76.62 ± (SD) 10.83 % of coral species are bleached up to a water depth of 10–15 m. Species from the genus Acropora appeared more susceptible to bleaching than those belong to the genus Porites. During the month of June 2010 the sea surface temperature was reduced to 29 °C perhaps due to the rainfall which stimulated rebuilding of zooxanthellae population in bleached corals. Recovery of 85.54 ± (SD) 6.33 % of bleached corals was seen during the study period of 11 months after the bleaching event. Porites spp. showed a high recovery rate, while Acropora spp. had the highest mortality rate. Coral mortality can have profound ecological and socio-economical implications and highlights the need for sustained monitoring for coral reef conservation in India. Hence, steps must be taken to improve management tools to protect these resources of global significance.
      PubDate: 2014-12-01
       
  • Immunolocalization of Glucagon and Insulin Cells in Endocrine Pancreas and
           Cyclic Disparity of Plasma Glucose in the Lizard        class="a-plus-plus">Psammophilus dorsalis
    • Abstract: Reptiles are an interesting group to study the physiology of reproduction. As information on mobilisation of glucose and associated endocrine alterations in the pancreas are not known, a study on the lizard Psammophilus dorsalis was undertaken using immunohistochemistry. Glucagon-immunoreactive (IR) and insulin-IR cells never formed islets instead spread throughout the pancreas in P. dorsalis. Glucagon-IR cells appeared to release the secretory granules from all over the surface, insulin-IR cells are unidirectional in their secretion. Both cell types often have no direct contact with capillaries. The morphometric analysis showed that the glucagon-IR cells were the most abundant amounting approximately 63 % as against insulin-IR cells, amounting approximately to 37 % of the endocrine pancreatic mass in the present study. On an average P. dorsalis exhibited 288.3 ± 25.28 mg% of plasma glucose, the abdominal fat underwent clearance as there was energy demand during reproductive and recrudescent periods. Glycogen granules were evident in liver and this was inversely related with plasma glucose.
      PubDate: 2014-12-01
       
  • Macrozoobenthic Community and Assessment of Aquatic Ecosystem Health of
           three Waterbodies of East Calcutta Wetlands, India
    • Abstract: The present study was aimed to understand the diversity, abundance and distribution of macrozoobenthic community of three selected fishponds differing in sewage intake and culture practices of East Calcutta Wetlands of Kolkata, India, as well as the aquatic ecosystem health of these waterbodies considering benthos as the best indicator of pollution. One year seasonal samplings were done to study the diversity and distribution of macrozoobenthos along with 12 water quality parameters to reflect the ecological conditions and aquatic ecosystem health of these waterbodies through biodiversity indices and statistical analysis (SPSS 10). A total of 27 species of macrozoobenthic organisms belonging to 18 families under four phyla comprising eight major groups viz. Polychaeta, Oligochaeta, Hirudinea, Diptera, Odonata, Gastropoda, Bivalvia and Pisces have been recorded. The diversity of macrozoobenthic fauna of these three waterbodies revealed that Ruby wetland had the highest representation of 24 species followed by Sukantanagar pond (17 species) and Sukantanagar bheri (16 species). The result of Pearson’s correlation coefficient showed that amongst the collected macrozoobenthos the gastropod species, Bellamya bengalensis and Lymnaea acuminata were wetland site-wise significant. The total benthic population and biomass have positive correlation with water transparency and organic enrichment of the waterbody. Shannon Weiner and Margalef’s indices have revealed higher values for Ruby wetland. Biodiversity indices and BMWP Score System designated to benthic organisms, suggested Ruby wetland is healthier than the other two waterbodies, differing in sewage intake and culture practices.
      PubDate: 2014-12-01
       
  • On the Record of a Spot-Fin Porcupine Fish,        class="a-plus-plus">Diodon hystrix (Linnaeus,
           1758) from Mandarmani, Bay of Bengal Coast of West Bengal, India
    • Abstract: A dead specimen of a spot-fin porcupine fish Diodon hystrix was observed on the sea shore in Mandarmani, West Bengal, India. The fish weighed 2.7 kg, 76.5 cm in length and 2.54 cm in eye diameter. Although distributed circumtropically and recorded from Indian coastal waters, D. hystrix is not harvested at present, as a part of commercial capture fishery. Scars and symptoms ensuring trawler net trap caused death of the specimen. This incident warrants for a strict vigil on fishing gear used in this part of Bay of Bengal so as to ensure death escape of non-target marine resources.
      PubDate: 2014-12-01
       
  • Annual Cyclical Changes in the Histological Features and Surface
           Ultrastructure in Ovaries of the Freshwater Featherback        class="a-plus-plus">Notopterus notopterus (Pallas,
           1769)
    • Abstract: The feather back, Notopterus notopterus is an important food fish. Its ovary is an extremely dynamic organ and the oocytes present an asynchronous development. Variations in ovary weight, GSI, diameter of oocytes were studied in different months of the year in this fish. Different developmental stages of female germ cells were identified on the basis of histological and ultrastructural characteristics in the ovary of N. notopterus (Pallas). In the present investigation the oocyte development of N. notopterus was divided into five stages (oogonia, perinucleolar oocyte, cortical alveolus, yolk granules stage and mature oocyte). The cytophysiological features like vitellogenesis, chorion formation and atresia of some follicles were also studied in the present investigation. The seasonal changes in the ovary have been described according to the variations in gonadosomatic index and the cytological changes of the female germ line cells.
      PubDate: 2014-12-01
       
  • Induction of Apoptosis in G       class="a-plus-plus">1/S Blocked HeLa Cells by
           R-Roscovitine: A Preliminary Study
    • Abstract: HeLa cells are human cervical cancer cells with HR HPV-18 genes integrated in the genome. The functions of tumor suppressor proteins p53 and pRB are abrogated and cell cycle regulation becomes nonfunctional. The aim of the present study was to investigate whether the CDK inhibitor R-Roscovitine would allow the G1/S blocked HeLa cells to enter into mitosis prematurely and induce apoptosis. HeLa cells blocked in G1/S border were treated with different concentrations of Roscovitine for 4 and 18 h respectively. Induction of apoptosis was studied by FACS and DNA fragmentation. Presence of γH2AX in the treated cells was studied by confocal microscopy. Expression levels of CASP3, CDKN1A i.e. p21 (Cip1/Waf1) and Bcl2 were studied by semi-quantitative RT-PCR to analyze the role played by these proteins in Roscovitine induced apoptosis in G1/S blocked HeLa cells. Results indicate that the Roscovitine allowed the thymidine blocked HeLa cells to enter into mitosis prematurely. Presence of γH2AX loci in treated cells indicates DNA damage in prematurely mitotic cells. Analysis of DNA fragmentation and chromatin condensation confirmed apoptosis as the possible mechanism of Roscovitine induced cell death. Our results also reveal that Roscovitine induced apoptosis is associated with the overexpression of CASP3, p21 (cip1/waf1) and Bcl2.
      PubDate: 2014-12-01
       
  • Photoperiod as Cues for Determining Optimal Foraging in Developmental
           Stages in Chitala
           chitala
    Hamilton, 1822
    • Abstract: Photoperiod plays an important role in controlling the feeding rhythmicity of juvenile fishes. Studies on feeding and spatial distribution pattern were made on wild populations of different juvenile stages of Chitala chitala, a threatened species in India. Results indicated that the prey preference of the fish increased with advancement of developmental stages. Moreover, nocturnal feeding was found to be more significant in the juveniles. Thus, feeding pattern of the different juvenile stages of Chitala is characterized by voracious predatory activity at dark condition. The vector controlling potential of the juvenile stages of Chitala specifically on mosquito and chironomid larvae was also significant. Studies on the distribution pattern of juvenile fishes were made with various combinations, viz. with or without food, in open surface and structured environments and observed during day as well as in dark regime. The juvenile distribution was clumped in open and closed environment during day time to minimize the chances of predation and juvenile mortality irrespective of food availability. A random distribution of juvenile fishes seemed to be advantageous for increasing feeding activity as observed in the experiment. This study is a pointer to the survival strategy of the larvae of C. chitala in their natural habitat which may be important from the perspective of conservation.
      PubDate: 2014-12-01
       
  • Polysaccharides as Constituents in Chromosome Organization: A Study on
           Meiotic Chromosomes of Grasshopper and Polytene Chromosomes of Dipterous
           Flies
    • Abstract: Study on meiotic chromosomes of grasshopper, Gesonula punctifrons and interphase polytene chromosomes from Dipteran larvae as of Chironomus striatipennis and Drosophila melanogaster following staining by periodic acid-Schiff technique revealed that chromosomes contained polysaccharides as an integral part of their organization. PAS +ve nature of the chromosomes both at highly condensed state as available during meiotic cell division and at extended state as in polytene chromosomes supports the idea that chromosomes contain polysaccharides as one of the constituent biological macromolecules. PAS +ve chromosomes appeared to be fluorescent under fluorescence microscope and fluorescence was found to be more or less uniform along the whole length of the meiotic chromosomes, while in case of polytene chromosomes intense fluorescence could be noticed along the band regions of the chromosomes.
      PubDate: 2014-10-15
       
  • Alterations in Digestive Enzymes of Three Freshwater Teleostean Fishes by
           Almix Herbicide: A Comparative Study
    • Abstract: Abstract Three freshwater teleostean fishes viz., Anabas testudineus (Bloch), Heteropneustes fossilis (Bloch) and Oreochromis niloticus (Linnaeus) were exposed to almix (66.67 mg/l) herbicide for 30 days to investigate the activity of digestive enzymes (amylase, lipase and protease) in stomach, intestine and liver. Amylase activity showed significantly high (p < 0.05) in all the fishes compared to control value and highest activity was observed in liver of A. testudineus (721.99 %) and minimum in intestine of H. fossilis (195.37 %). Lipase activity was also significantly increased (p < 0.05) in all the tissues; but highest in intestine of O. niloticus (235.51 %) and minimum in intestine of A. testudineus (130.51 %). Protease activity also showed similar trends of enhancement; it was maximum in stomach of O. niloticus (362.69 %), whereas in liver of H. fossilis it was rather less (173.72 %). Increased activity of digestive enzymes resulting from tissue damage ultimately affected the fish health due to impairment of digestive physiology confirming the herbicidal contamination on fish species. The sensitivity to the almix herbicide was pronounced in the order of O. niloticus > A. testudineus > H. fossilis.
      PubDate: 2014-10-02
       
  • Allozyme polymorphism in        class="a-plus-plus">Drosophila
    • Abstract: Abstract Every population possesses genetic variations which are achieved through gene mutation, genetic recombination, hybridization, gene duplication etc. These genetic variations provide raw materials for evolutionary forces to create a better surviving species. Genetic polymorphism is reflected at every level in the populations, for example, at phenotypic, chromosomal, protein and DNA levels. Protein or enzyme polymorphisms have been well studied in various organisms including Drosophila and humans. Drosophila has proven to be a good model organism for carrying out polymorphism studies. Among the different species of Drosophila, there is a wide variation in the levels of allozyme polymorphisms and heterozygosities which depends upon species, geographical regions, number and nature of loci in question etc. In Drosophila, the average polymorphic enzyme loci and average heterozygosity ranges from 35 to 70 percent and 10 to 20 percent respectively. The genetic differentiation as observed through allozyme or isozyme variation affords an important parameter in evaluating the phylogenetic relationships between different species of Drosophila and also for discussing the adaptive significance of allozyme polymorphisms. Therefore, this review attempts to compile all studies on allozyme polymorphism in Drosophila that have been undertaken so far.
      PubDate: 2014-09-27
       
  • Effects of Probiotics on Survival, Growth and Digestive Enzymes Activities
           in Freshwater Prawn Macrobrachium
           rosenbergii
    (De Man 1879)
    • Abstract: Abstract A study was conducted to examine the effects of three probiotics, Lactobacillus sporogenes, Bacillus subtilis and Saccharomyces cerevisiae on the survival, growth and digestive enzymes activities of the freshwater prawn Macrobrachium rosenbergii post larvae (PL). The probiotics, L. sporogenes (4 %), B. subtilis (3 %) and S. cerevisiae (4 %) were taken and mixed with basal diet. Diet without probiotics served as control. These probiotics diets were fed to M. rosenbergii PL for a period of 60 days. After the feeding trail, the growth parameters such as survival, weight gain, specific growth rate and protein efficiency rate were found to be significantly (P < 0.05) higher in 4 % S. cerevisiae incorporated diet fed PL when compared with control. In the case of feed conversion rate just the reverse was seen (P < 0.05) at this concentration. This indicates its superior quality among different concentrations of probiotics tested. Activities of digestive enzymes, such as protease, amylase and lipase were significantly (P < 0.05) higher at this concentration (4 % S. cerevisiae). Some of essential and non-essential amino acids also significantly elevated in probiotics supplemented diet fed prawns. This study indicated that probiotics, S. cerevisiae incorporated diets were beneficial for M. rosenbergii in terms of increasing growth, enzyme and amino acid production.
      PubDate: 2014-09-27
       
  • Avian Diversity in Agricultural Landscape: Records from Burdwan, West
           Bengal, India
    • Abstract: Abstract Avian species assemblages are potential indicators of integrity and stability of ecosystem structure and functions. Characteristic avian fauna in landscapes enable predictions about the environmental state and possible deviations in the ecosystem functions. Documentation of avian species assemblages in different landscapes are therefore being emphasized from environmental monitoring perspective. As a primary effort, the present commentary depicts the avian species assemblage of agricultural landscapes, using Burdwan, West Bengal, India, as a study area. Employing line-transect method of continuous survey and opportunistic encounter, a total of 144 bird species under 51 families and 19 orders were recorded from the study area. The avian species richness was highest for the order Passeriformes followed by Charadriidae and rest 17 orders. Resident, local migrant and migrant species constituted 61.15, 31.65 and 7.20 % of the bird community, respectively. Most of the bird species (51.85 %) were associated consistently with the agricultural fields as their habitat followed by aquatic systems (29.20 %) and human habitat (18.98 %). The study records the presence of three species under IUCN Near Threatened category and many species exhibiting sparse population based on the encounter rate and number of individuals in the habitat. The observed richness of bird species in the study area calls for further studies on habitat preference, census and breeding biology to highlight species specific roles in ecosystem functions and sustenance of ecosystem services.
      PubDate: 2014-09-26
       
  • Ethno Veterinary Practices Prevalent Among Livestock Rearers at Arbe Gona
           And Loka Abaya Woredas of Sidama Zone of Southern Ethiopia
    • Abstract: The use of ethno veterinary medicine as practiced among the residents of Arbe Gona and Loka Abaya woredas has been discussed. The study was conducted using semi structured questioner, focus group discussion and personal interviews. The respondents were identified by stepwise purposive sampling procedures. The study indicates that ethno veterinary medicine has been practiced among the agrarian community in the region since time immemorial. The results indicate that the practice is mostly a family affair with the knowledge transferred from the elders to the youngsters within a family. Thirty seven different types of medicinal herbs/plants used in ethno veterinary drug preparation were identified, the most commonly used plant part was the leaf followed by other plant parts viz. xylem, roots, barks etc. Mostly the drugs were used through oral route. Though topical application, fumigation and intravenous route of administration of the drugs too are on record. Twenty two commonly occurring diseases were identified by the respondents and their treatments too have been discussed. Use of different parts of several plants in unison is the common practice. The results also indicated that the medicinal plants are mostly collected from the wild and are under threat due to both ecological and anthropogenic factors and hence need conservation. The study also revealed that the millennia old practice is under threat due to lack of enthusiasm from the younger generations to take up the baton from the elder generation.
      PubDate: 2014-09-17
       
  • Enhancement of Resistance vis-à-vis Defence-Enzyme Activity in Tea
           Mosquito Bug, Helopeltis
           theivora
    Waterhouse (Hemiptera: Miridae) Selected Through
           Exposure to Sub-lethal Dose of Monochrotophos
    • Abstract: Tea industry is the back bone of agro-economy of the tea producing regions. Tea mosquito bug, Helopeltis theivora Waterhouse is one of the most devastating sucking pests of tea and is a menace to tea plantations of North Bengal and other states of NE India. Insecticide forms the mainstay of pest management programme in tea plantations. Insecticide stress and selection have led to the development of high tolerance or resistance in many pests including the sucking bug H. theivora. LC50 value of an organophosphate insecticide, monochrotophos (SL 36 %) to this species increased about 105 fold when selected by exposure to sub-lethal dose for three generations. Generation-wise relative tolerance level when selected by sub-lethal dose of monochrotophos showed a significant increase in 1st and 2nd filial generations as compared to the parental generation (P < F1 < F2). General esterases (GE) activity got enhanced by 5.32 and 16.4 fold, and the activity of cytochrome P450 monooxygenases (CYP) increased by 1.96 and 9.50 fold in F1 and F2 generations respectively as compared to parental generation. The generation-wise increase in relative resistance and the activity of defence enzymes were found to have high positive correlation; r = 0.999 for GE and r = 0.994 for CYP. The study suggests that the titres of GE and CYP in H. theivora can be used as the markers of relative tolerance to insecticides in general, with mode of action similar to monochrotophos. Such defence-enzyme based detection technique for tolerance levels may help early identification of resistant population of H. theivora; hence its management.
      PubDate: 2014-09-11
       
 
 
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