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The present study was undertaken to determine distribution of thrips species from major tomato growing regions in South India (Tamil Nadu, Karnataka, Maharashtra, Telangana, Andhra Pradesh). The thrips species were identified using molecular techniques employing universal barcoding primer (mt-COI). These revealed the presence of six species viz., Thrips palmi Karny, Scirtothrips dorsalis Hood, Thrips tabaci Lindeman, Frankliniella schultzei (Trybom), Thrips apicatus Priesner and Tusothrips sumatrensis (Karny). Of these, T. palmi was found to be predominant in all the states surveyed followed by S. dorsalis, F. schultzei and T. tabaci. [ABSTRACT FROM AUTHOR]

Several termite species are significant economic pests, causing damage to wood in both man-made structures and also in forest ecosystem. The species belongs to genus Coptotermes (Rhinotermitidae: Isoptera: Blattodea) are widespread and few of them are among the world's most dangerous wood pests. Two species of Coptotermes were collected, identified and described from yemene, mora and tali logs imported from Columbia, Suriname and Equitorial Guinea. These two intercepted species are non-native to India which are Coptotermes testaceus (Linnaeus) and Coptotermes sjöstedti Holmgren. Identification was initially made with morphological characters and then with molecular DNA barcoding for a 348 bp fragment of 16S rRNA gene. Maximum likelihood Phylogenetic analysis results showed that data recovered as monophyletic which confirms the species identity. Coptotermes testaceus and C. sjöstedti are in single clade. Coptotermes testaceus is neotropical in origin and C. sjöstedti is native to Africa. Both the species are known to be serious pests in human habitats and forest ecosystem in the regions of their distributions. This first interception suggests possible chances of entry and establishment in India and provides an important alert for authorities concerned to take the necessary steps in monitoring and preventing its possible introduction. The importance of quarantine and potential infliction of damage they may cause if unnoticed and future measures to be taken are discussed. [ABSTRACT FROM AUTHOR]

Tospoviruses (Bunyavirales) which are exclusively transmitted by thrips cause server yield loss on vegetables. In this regard, out of 6000 species of thrips, only 16 species have been reported to be the vectors of different tospovirues worldwide. In this regard, a member of the tospovirus called groundnut bud necrosis virus (GBNV) is known to infect groundnut has become one of the production constraint on tomato in India since for few years. In this regard there is no definitive information available on the species of thrips involved in transmission of GBNV to tomato in India. Therefore, a survey was carried out to determine different species of thrips available in the tomato ecosystem at the ICAR - IIHR experimental farm, Bengaluru during 2019. Species diagnosis of the thrips specimens was carried out using ITS2 and mtCOI markers. Results revealed the prevalence of four thrips species viz., Thrips palmi, Scirtothrips dorsalis, Frankliniella occidentalis and T. hawaiiensis of which T. palmi was predominant. [ABSTRACT FROM AUTHOR]

The fall armyworm (FAW) was discovered in India after leaving a path of ruined plants in Africa and the Americas. The present work aimed to isolate and identify Bacillus thuringiensis (Bt) isolates active against FAW. A total of 10 putative Bt isolates were acquired. FAW Bt isolates were Gram-positive and crystalliferous as examined under light and scanning electron microscopy. Bipyramidal crystals were predominantly observed. Molecular characterization of Bt cry gene was done by polymerase chain reaction analysis that revealed the presence of cry1, cry1B, and cry1I genes. SDS-PAGE analysis of FAW Bt isolates showed the presence of bands 130, 73, 34, 25, and 13 kDa, among which 50-66 kDa were abundantly present. We also assessed the insecticidal activity for the effective FAW management. Toxicity of isolates was determined against first to fourth instar larvae of FAW. Mortality after treatment recorded was 88.88-100% compared to controls where no mortality was observed and larvae completed the lifecycle successfully. The present studies provide the FAW specific Bt isolates with potential impact and control of this insect pest. [ABSTRACT FROM AUTHOR]

South American tomato moth, Tuta absoluta is one of the major destructive invasive pest globally. The pest was reported from India during 2014 and is spreading to various states very rapidly causing extensive damage on solanaceous crops, particularly on tomato. Natural incidence of green muscardine fungus, Metarhizium anisopliae infecting T. absoluta larva on tomato was observed for the first time in India causing up to 35% mortality. A laboratory study was carried out to assess the pathogenicity and effectiveness of M. anisopliae against T. absoluta during 2016-17, using the leaf immersion method. Hundred per cent mortality was recorded at a concentration of 1x109spores/ml at 120 hours after treatment with LC50 of 9.03×105 spores/ml. [ABSTRACT FROM AUTHOR]

South American tomato moth, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is an invasive pest on tomato and other solanaceous crops. In general, 20 to 30 % yield loss is caused by this pest and sometimes it may result in 100% damage, if timely management interventions are not followed. Though the pest was reported in India during 2014, presently it has spread to several tomato growing states. In the present study various IPM tools have been evaluated against this pest. As a long-term strategy of resistance breeding, genotype screening was carried out for identification of resistance sources from wild and cultivated tomato genotypes showing resistance/tolerance against T. absoluta. Among the evaluated wild and cultivated tomato genotypes, Solanum pennellii (Accession, LA 1940) was identified as a resistant source against T. absoluta both under choice and no-choice bioassays and is being used for resistance breeding. Various entomopathogens (Bacillus thuringiensis, Metarhizium anisopliae, Beauveria bassiana and M. rileyi), egg parasitoids (Trichogramma chilonis, T. pretiosum and Trichogrammatoidea bactrae), light traps, pheromone traps, synthetic insecticides, botanical origin insecticides were also evaluated for their relative efficacy. Among the egg parasitoids T. pretiosum and among synthetic chemicals, spinetoram 12 SC@ 1.25ml/l were found very effective for the management of T. absoluta. Yellow light traps were found as an effective component for integrated management of T. absoluta. Azadirachtin 5% EC at the tested concentrations showed highest mean radial growth (24.67 mm) with relatively less inhibition (16.51%) of M. anisopliae indicating these combinations can be effectively utilised in the eco-friendly management of T. absoluta. We reported natural incidence of M. anisopliae on T. absoluta larvae, causing up to 35 per cent mortality during 2016-17. [ABSTRACT FROM AUTHOR]

The invasion of the Western Hemisphere native fall armyworm (Spodoptera frugiperda; J. E. Smith) (Lepidoptera: Noctuidae) into the Eastern Hemisphere has been notable for the rapidity and geographical breadth of new detections. In the year following the first discovery in western sub-Saharan Africa in 2016, infestations have been documented in most sub-Saharan maize growing regions and has now expanded beyond Africa with populations recently reported in India. These observations could indicate a remarkable capacity for rapid establishment and long-distance dissemination. However, while fall armyworm does exhibit extended migration in North America where it annually traverses thousands of kilometers, this behavior is known to be dependent on highly favorable wind patterns and so can’t be assumed to occur in all locations. An alternative possibility is that the species has long been present in Africa, and perhaps the rest of the hemisphere, but was undetected until the enhanced monitoring that resulted after its initial discovery. Determining whether the fall armyworm in the Eastern Hemisphere is newly arrived or long pre-existing is important for assessing the risks of significant economic impacts, as the former indicates a change in pest composition while the latter does not. This study examined this issue by comparing collections from two geographically distant locations, South Africa and India. Sequence comparisons were used to quantify differences between the South Africa and India collections, assess the likelihood of their sharing a common source population, and their possible relationship with previously characterized fall armyworm from other regions of Africa. The results indicate genetic homogeneity between the South African and Indian fall armyworm populations tested and substantial similarities between these and collections from eastern Africa. The implications of these findings on fall armyworm population behavior and composition are discussed. [ABSTRACT FROM AUTHOR]

Kidney diseases are silent killers, which largely affect the quality of life. As the kidney function slows the symptoms of uremia are experienced includes feeling of tired or weak, shortness of breath, loss of appetite, nausea, vomiting, etc. Fatigue is a debilitating symptom experienced by CRF patients. Fatigue has a considerable effect on patients health related quality of life. A study is conducted to evaluate the effectiveness of warm footbath on fatigue among patient with chronic renal failure. A one-group pretest posttest design is used for the present study. The study is conducted at the Pradyumna Bal Memorial Hospital (KIMS) in Nephrology unit (both male and female) ward. Sample size consists of 30 hospitalized CRF patients who met the inclusion criteria by using the purposive Sampling technique. Structured interview schedule of Piper fatigue Scale is used to assess the fatigue. The study started with pre assessment and followed by warm footbath given. Footbath procedure is held for 30 minutes upto 7 days. The mean posttest score (y=2.76) is lower than the mean pretest score (x=7.19). The paired t test is found to be highly significant and the P less than 0.001. Based on the chi-square values and the P values obtained in the following demographic variables has the significance such as age, sex, education, occupation and years of suffering with CRF. The study concluded that the warm footbath is effective in reducing the fatigue of patients with CRF. [ABSTRACT FROM AUTHOR]

Rapid, precise and timely identification of invasive pest insects such as aphids is important and a challenge worldwide due to their complex life cycles, parthenogenetic reproduction, sex and colour morphs. In this respect, DNA barcoding employing a 658 bp fragment of 5′ region of the mitochondrial cytochrome oxidase I (CO-I) gene is an effective tool in addressing the above. In the present study, we employed CO-I for discriminating 142 individuals representing 32 species of aphids from India. Sequence analyses revealed that the intraspecific and interspecific distances ranged from zero to 3.8% and 2.31 to 18.9%, respectively. In addition, the study also showed for the first time the prevalence of three cryptic species, namely Brevicoryne brassicae (Linnaeus), Hyperomyzus carduellinus (Theobald) and Brachycaudus helichrysi (Kaltenbach) from India. Our work has clearly demonstrated that DNA barcoding is an efficient and accurate method for identification of aphid species (including cryptic species), an approach that potentially could play an important role in formulating viable pest management strategies, more especially biocontrol. [ABSTRACT FROM PUBLISHER]

Rapid, accurate, and timely identification of insects as a group is important and challenging worldwide, as they outnumber all other animals in number and diversity. DNA barcoding is a method for the identification of species in a wide range of animal taxa, which uses the 5' region of the mitochondrial cytochrome c oxidase-I (CO-I). Yet another easy, accurate, and economical method of species discrimination is by developing species-specific markers, which produce specific amplicon for the species in question. The method is handy because it is not limited by life stages, sex, polymorphism, and other factors. Herein, we measured the usefulness of CO-I for the species discrimination of mirids in India viz. Helopeltis antonii Signoret, H. thievora Waterhouse, H. bradyi Waterhouse, and Pachypeltis maesarum Kirkaldy in their various life stages. Furthermore, our study showed the utility of species-specific markers in differentiating H. antonii (295) and H. bradyi (514) regardless of their life stages. Analysis of CO-I gene revealed <1% intraspecific divergence for all four species examined, whereas the interspecific distances ranged from 7 to 13%. This study showed that the DNA barcode and species-specific markers will aid the identification of mirids in India and will stand as a decisive tool in formulating integrated pest management (IPM) strategy, quick identification of invasive and cryptic species, haplotypes, biotypes, and other factors, if any. [ABSTRACT FROM AUTHOR]

Nearly 6000 species of thrips have been described and only 12 species are reported to be vectors of tospoviruses (Bunyaviridae) globally In this regard, Thrips palmi and Scirtothrips dorsalis are two important vectors of Watermelon Bud Necrosis Virus (WBNV) and Peanut Yellow Spot Virus (PYSV) to watermelon and groundnut respectively in India. Accurate and timely identification of thrips vectors in the early developmental stages is important for understanding the epidemiology of tospoviruses, their management and also in quarantine. Morphological identification of thrips often has been a stumbling block in the absence of trained personnel. Using the tools of molecular biology, morphological identification is further strengthened by developing species-specific markers, which can differentiate the above two species of thrips based on the PCR amplicon size. Molecular studies can elucidate the occurrence of biotypes or cryptic species, if any. In this study, we examined genetic differences in COI among 21 populations of T. palmi collected from Karnataka, India, along with the sequences from other countries which were acquired from GenBank. The phylogenetic analysis showed that there are two major groups: one is clearly associated with Indian population of T. palmi and the second is associated with the remaining countries (Japan, Thailand, Dominican Republic, China, and U.K.). Our studies clearly refute the general belief that T. palmi is a single cosmopolitan and polyphagous species. On the contrary, by the standards of genetic and ecological differentiation in other species groups, the recognition of geographically associated and distinct T. palmi subspecies may be considered, similar to what has been observed in T. tabaci. Such similar results have been observed for S. dorsalis, where Indian and Chinese population of S. dorsalis form separate groups. [ABSTRACT FROM AUTHOR]

Some species of mirids are major pests of cashew damaging tender shoots, inflorescence, immature nuts, and apples at various stages of development. In India, crop loss is often more than 40% in cashew alone, and the genus Helopeltis closely resembles the genus Pachypeltis. Using molecular biology tools, morphological identification is further strengthened by DNA barcoding (using COX-1) and development of species-specific markers, which helps a non-specialist to identify a species. The molecular identification of Helopeltis and Pachypeltis spp. has been corroborated with morphological identification. The investigation results help in quick, accurate, and timely identification of Helopeltis antonii and Pachypeltis maesarum, a critical factor in understanding the epidemiology of the crop losses in cashew, their management and also in quarantine. [ABSTRACT FROM AUTHOR]

Bt strains were isolated from soils of Andaman and Nicobar Islands and characterized by microscopic and molecular methods. Diversity was observed both in protein and cry gene profiles, where majority of the isolates showed presence of 65 kDa protein band on SDS-PAGE while rest of them showed 130, 72, 44, and 29 kDa bands. PCR analysis revealed predominance of cry1I and cry7, 8 genes in these isolates. The PCR screening strategy presented here led us to identify putative novel cry genes which could be active against Coleoptera insects. Variation in the nucleotide sequences of cry genes from the isolates suggests that the genetic diversity of Bt isolates results from the influence of different ecological factors and spatial separation between strains generated by the conquest of different habitats in the soils of Andaman and Nicobar islands. The implications of our studies are important from the point of view of identifying novel cry genes that could be toxic to insects other than lepidoptera. [ABSTRACT FROM AUTHOR]

Mealybugs are major factors limiting the productivity of papaya in India. In June 2012 during a survey for the papaya mealybug, Paracoccus marginatus, and its parasitoid Acerophagus papayae, in Satyamangalam, Tamilnadu, India, a short tailed mealybug was found together with P. marginatus colonizing papaya in 2 plantations. This mealybug was identified as the Jack Beardsley mealybug, P. jackbeardsleyi Gimpel and Miller (Hemiptera: Pseudococcidae), by an integrated taxonomic approach. This work appears to be the first report of P. jackbeardsleyi in India and of papaya as a host of this pest. [ABSTRACT FROM AUTHOR]

Purpose: Environmental and genetic factors are associated with development of Pseudoexfoliation syndrome (XFS). Here we intended to elucidate the association of candidate genes in relevance to UV exposure in these patients., Methods: This is a case-control study of 309 subjects ( N  = 219 controls and 90 XFS cases) from India. PCR based direct sequencing was performed for candidate genes ( LOXL1, POMP and TMEM136 ) followed by genotype and haplotype analysis. The promoter methylation status was assessed by Methylation specific PCR based direct sequencing of genomic DNA for all samples. The methylation status was compared with that of primary fibroblasts cultures established from patient's Tenon's tissue samples in subset of these patients., Results: SNPs rs3825942, rs41435250, rs8818 ( LOXL1 ) and rs3737528 ( POMP ) showed significant association with XFS. LOXL1 gene haplotype GAGC (rs1048661- rs3825942- rs41435250-rs8818) was associated with lower risk for XFS with a p value 4.1961 × 10 -6 (OR =0; 95%CI, 0.000-0.003). POMP gene haplotypes for intronic SNPs (rs1340815- rs3737528- rs913797) TCC and TTC were associated with increased risk for the disease (OR > 1.0). Significant correlation for SNPs rs3825942 of LOXL1 (ρ= -0.132) and rs3737528 of POMP (ρ = 0.12) was observed with measure of lifetime UV exposure (CUVAF value). Reduced LOXL1 gene expression was observed in cultured tenon fibroblasts from the patients that correlated with differential methylation of the Sp-1 binding sites at -253, -243bp upstream to the transcription start site of LOXL1 promoter region., Conclusion: Our results suggest a possible interaction for LOXL1 gene haplotype (GAGC) with the measure of ocular UV exposure in pseudoexfoliation syndrome.

The South American tomato moth, Phthorimaea absoluta (Meyrick), is one of the key pests of tomato in India. Since its report in 2014, chemical control has been the main means of tackling this pest, both in the open field and protected cultivation. Despite regular insecticidal sprays, many outbreaks were reported from major tomato-growing regions of South India during 2019-2020. A study was conducted to investigate the effect of insecticide resistance on biology, biochemical enzymes, and gene expression in various P. absoluta field populations viz ., Bangalore, Kolar, Madurai, Salem, and Anantapur to commonly used insecticides such as flubendiamide, cyantraniliprole, and indoxacarb. Increased levels of insecticide resistance ratios (RR) were recorded in P. absoluta populations of different locations. A significant increase in cytochrome P450 monooxygenase (CYP/MFO) and esterase levels was noticed in the resistant population compared to susceptible one. Through molecular studies, we identified four new CYP genes viz ., CYP248f (flubendiamide), CYP272c, CYP724c (cyantraniliprole), and CYP648i (indoxacarb). The expression levels of these genes significantly increased as the folds of resistance increased from G1 to G20 (generation), indicating involvement of the identified genes in insecticide resistance development in P. absoluta . In addition, the resistant populations showed decreased fecundity, increased larval development period, and adult longevity, resulting in more crop damage. The information generated in the present study thus helps in understanding the development of insecticide resistance by P. absoluta and suggests the farmers and researchers to use insecticides wisely by adopting insecticide resistance management as a strategy under integrated pest management.

Purpose: Studies have reported the usage of metformin being associated with the reduced risk of progression of glaucoma. The current study aims to determine the association of metformin usage among subjects with diabetes mellitus and the six-year incidence of primary open-angle glaucoma (POAG)., Methods: In this prospective cohort study, subjects who did not have glaucoma at the baseline and had a follow-up after a six-year interval were included. Details such as medical and drug history, applanation tonometry, gonioscopy, pachymetry, optic disc evaluation, and automated perimetry were collected. Incident POAG was defined as subjects who do not have glaucoma at baseline and developed glaucoma as classified International Society of Geographical and Epidemiological Ophthalmology Classification at the follow-up. The association between the subjects who were on metformin for treatment of diabetes mellitus and development of incident POAG was assessed., Results: Among the 4302 eligible participants, 128 (3%) had incident POAG. There were 905 (21.0%) subjects who had diabetes mellitus of which 142 (15.7%) were using metformin. Of the subjects with POAG, 92 (71.9%) were nondiabetics and 36 were diabetics (28.1%). Among the diabetics, the incidence of POAG among those on metformin was 5.6% (8 participants) and those not on metformin was 3.6% (28 participants). There was no difference in the incidence of POAG in subjects with diabetes mellitus, with and without metformin use (P = 0.25). Logistic regression showed no association of metformin use with the incidence of POAG (OR: 1.33, 95 CI: 0.58-3.04, P = 0.49) after adjusting for age, gender, and place of residence., Conclusion: The current study did not find any association between the effects of metformin on the incidence of POAG., Competing Interests: None

The gut microbial community structure of adult Thrips tabaci collected from 10 different agro-climatically diverse locations of India was characterized by using the Illumina MiSeq platform to amplify the V3 region of the 16S rRNA gene of bacteria present in the sampled insects. Analyses were performed to study the bacterial communities associated with Thrips tabaci in India. The complete bacterial metagenome of T. tabaci was comprised of 1662 OTUs of which 62.25% belong to known and 37.7% of unidentified/unknown bacteria. These OTUs constituted 21 bacterial phyla of 276 identified genera. Phylum Proteobacteria was predominant, followed by Actinobacteria, Firmicutes, Bacteroidetes and Cyanobacteria. Additionally, the occurrence of the reproductive endosymbiont, Wolbachia was detected at two locations (0.56%) of the total known OTUs. There is high variation in diversity and species richness among the different locations. Alpha-diversity metrics indicated the higher gut bacterial diversity at Bangalore and lowest at Rahuri whereas higher bacterial species richness at T. tabaci samples from Imphal and lowest at Jhalawar. Beta diversity analyses comparing bacterial communities between the samples showed distinct differences in bacterial community composition of T. tabaci samples from different locations. This paper also constitutes the first record of detailed bacterial communities associated with T. tabaci. The location-wise variation in microbial metagenome profile of T. tabaci suggests that bacterial diversity might be governed by its population genetic structure, environment and habitat., Competing Interests: The authors have declared that no competing interests exist.

Purpose: To determine the prevalence of congenitally abnormal disc (all anomalies) in an adult population in southern India., Methods: Subjects aged ≥40 years (n=6013) underwent a complete ophthalmic examination. Optic disc anomalies were diagnosed according to the definitions given in the article., Results: Optic disc anomalies were found in 81 eyes of 66 (1.1%, 95% CIs 0.00834 to 0.01361) patients. The prevalence of each anomaly in the descending order was peripapillary myelinated nerve fibre (0.28%), epipapillary glial tissue on the optic disc (0.28%), peripapillary vascular loops (0.16%), tilted disc (0.09%), optic disc coloboma (0.08%), optic nerve hypoplasia (0.04%), optic disc pit (0.04%), optic disc pigmentation (0.03%), optic nerve head drusen (0.03%), Bergmeister's papilla (0.03%), optic disc pit and coloboma (0.01%)., Conclusions: The prevalence of optic disc anomalies is 1.1% in the adult South Indian population., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2019. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Purpose: To identify genetic risk factors contributing to central corneal thickness (CCT) in individuals from South India, a population with a high prevalence of ocular disorders., Methods: One hundred ninety-five individuals from 15 large South Indian pedigrees were genotyped using the Omni2.5 bead array. Family-based association for CCT was conducted using the score test in MERLIN., Results: Genome-wide association study (GWAS) identified strongest association for single nucleotide polymorphisms (SNPs) in the first intron of WNT7B and CCT (top SNP rs9330813; β = -0.57, 95% confidence interval [CI]: -0.78 to -0.36; P = 1.7 × 10-7). We further investigated rs9330813 in a Latino cohort and four independent European cohorts. A meta-analysis of these data sets demonstrated statistically significant association between rs9330813 and CCT (β = -3.94, 95% CI: -5.23 to -2.66; P = 1.7 × 10-9). WNT7B SNPs located in the same genomic region that includes rs9330813 have previously been associated with CCT in Latinos but with other ocular quantitative traits related to myopia (corneal curvature and axial length) in a Japanese population (rs10453441 and rs200329677). To evaluate the specificity of the observed WNT7B association with CCT in the South Indian families, we completed an ocular phenome-wide association study (PheWAS) for the top WNT7B SNPs using 45 ocular traits measured in these same families including corneal curvature and axial length. The ocular PheWAS results indicate that in the South Indian families WNT7B SNPs are primarily associated with CCT., Conclusions: The results indicate robust evidence for association between WNT7B SNPs and CCT in South Indian pedigrees, and suggest that WNT7B SNPs can have population-specific effects on ocular quantitative traits.

Background: Eye Movement Perimetry (EMP) uses Saccadic Eye Movement (SEM) responses for visual field evaluation. Previous studies have demonstrated significant delay in initiation of SEMs among glaucoma patients in comparison with healthy subjects. The aim of the current study was to develop an EMP-based screening grid to identify glaucomatous visual field defects., Methods: An interactive test consisting of 36 locations and two stimulus contrasts (162 cd/m 2 and 190 cd/m 2 on a background of 140 cd/m 2 ) was evaluated in 54 healthy subjects and 50 primary glaucoma patients. Each subject was presented a central fixation target combined with the random projection of Goldmann size III peripheral targets. Instructions were given to look at each peripheral target on detection and then re-fixate at the central fixation target while the saccades were assessed using an eye tracker. From each seen peripheral target, the Saccadic Reaction Time (SRT) was calculated for contrast level 162 cd/ m 2 . These values were used to plot Receiver Operating Characteristic (ROC) curves for each test locations and the Area Under the Curve (AUC) values were used to identify the locations with highest susceptibility to glaucomatous damage. Each stimulus location with an AUC less than 0.75 along with its mirrored test location around the horizontal axis were eliminated from the grid., Results: The mean age was 48.1 ± 16.6 years and 50.0 ± 14.5 years for healthy subjects and glaucoma patients respectively. A significant increase of SRT values by 76.5% (p < 0.001) was found in glaucoma patients in comparison with the healthy subjects. From the ROC analysis, ten out of 36 locations meeting the cut-off criteria of AUC were eliminated resulting in a new grid containing 26 test locations. SRT values were significantly different (p < 0.05) between the healthy subjects and glaucoma irrespective of the grids used., Conclusions: The present study resulted in a screening grid consisting of 26 locations predominantly testing nasal, superior and inferior areas of the visual field. An internal validation of the modified grid showed 90.4% of screening accuracy which makes it a potential approach for population based glaucoma screening.

The whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a phloem-feeding, economically important pest of crops worldwide. In addition to direct damage, it also vectors a number of plant viruses belonging to the family Geminiviridae. Its populations differ biologically with respect to insecticide resistance, virus transmission and host range. Therefore, understanding genetic variation among populations is important for management. We sequenced 850 bp of the mitochondrial COI (mtCOI) gene from B. tabaci populations surveyed across India. BLAST analysis of the mtCOI sequences generated in this study with sequences from the mtCOI dataset showed the presence of one invasive group, MEAM1, and eight other groups of B. tabaci in India. mtCOI sequence analyses showed the presence of Asia I, Asia I-India, Asia II-1, Asia II-5, Asia II-7, Asia II-8, and Asia II-11 genetic groups. We also found China-3 in a field in Birbhum district, West Bengal, India, suggesting a role of anthropogenic activities in the distribution of B. tabaci. Interestingly, more than one genetic group was found coexisting in the same field., (© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Objective: To estimate the 6-year incidence of pseudoexfoliation and its risk factors in a South Indian population., Design: Longitudinal population-based study., Participants: Subjects 40 years of age or older without pseudoexfoliation at baseline., Methods: Participants were examined at baseline and after a 6-year interval. The presence of pseudoexfoliation was looked for after pupillary dilation in either or both eyes at 1 or more locations. Glaucoma was defined using the International Society of Geographical and Epidemiological Ophthalmology Classification. Logistic regression was performed to identify the baseline risk factors that could predict the incident pseudoexfoliation., Main Outcome Measures: Six-year incidence, associated risk factors, and rural-versus-urban differences., Results: From the study cohort of 4228 subjects, 87 subjects (male-to-female ratio, 48:39; rural-to-urban ratio, 69:18) demonstrated incident pseudoexfoliation (2.03%; 95% confidence interval [CI], 1.6-2.5; rural: -2.86%; 95% CI, 1.6-2.5; urban: 0.96%; 95% CI, 0.5-1.4). Pseudoexfoliation was associated with glaucoma in 1 subject (1.1%), with primary angle-closure suspicion in 10 subjects (11.5%), and with ocular hypertension in 2 subjects (2.2%). Significant predictive baseline risk factors were older age (P < 0.001), rural residence (P < 0.001), illiteracy (P = 0.02), pseudophakia (P = 0.04), and nuclear cataract (P = 0.05). With reference to the 40-to-49-year age group, the risk of incidence increased from 4.7 (95% CI, 2.4-9.4) for the 50-to-59-year age group to 12.9 (95% CI, 6.1-27.2) for 70 years of age and older group., Conclusions: In 6 years, pseudoexfoliation developed in 2.03% of the population. Rural and urban incidence was significantly different., (Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Aims: To report the 6-year incidence and risk factors for ocular hypertension (OHT) in a population-based study in southern India., Methods: 6 years after baseline evaluation, 56.9% subjects (participants:non-participants, 4421:3353) were re-examined at the base hospital. Incident OHT was defined as an intraocular pressure above the 97.5th centile for the population with no evidence of glaucoma in the 2852 phakic subjects, 40 years or older. Subjects with trauma, laser or incisional surgery at baseline or follow-up were excluded (total exclusions: 1569)., Results: Incidence of OHT at 6 years was 62/2852 subjects (2.17% (95% CI 1.64% to 2.71%, men:women, 36:26)). Incidence was higher in the rural cohort as compared with the urban cohort (80.6% vs 19.4%, p<0.001). A higher baseline intraocular pressure (with increasing OR: 16-18 mm Hg (OR 4.0, 95% CI 2.1 to 7.9), 19-21 mm Hg (OR 11.4, 95% CI 5.7 to 22.9), 22-24 mm Hg (OR 42.6, 95% CI 11.0 to 164.8, in the urban cohort)) and increasing age (50-59 years (OR 1.9, 95% CI 1.1 to 3.3), 70 years and above (OR 3.6, 95% CI 1.2 to 10.6)) were significantly associated risk factors for incident OHT., Conclusions: A significant proportion of this normal population converted to OHT. A higher incidence of conversion was seen in the rural population., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Primary open angle glaucoma (POAG) belonging to a group of optic neuropathies, result from interaction between genetic and environmental factors. Study of associations with quantitative traits (QTs) is one of the successful strategies to understand the complex genetics of POAG. The current study attempts to explore the association of variations near/in genes like ATOH7, SIX1/SIX6 complex, CDKN2B, CARD10, and CDC7 with POAG and its QTs including vertical cup to disc ratio (VCDR), central corneal thickness (CCT), intra ocular pressure (IOP), and axial length (AL). Case-control study design was carried out in a sample size of 97 POAG cases and 371 controls from South India. Model-based (additive, recessive, dominant) association of the genotypes and their interaction was carried out between cases and controls using chi-square, linear and logistic regression methods. Nominal significance (P<0.05) was observed for QTs like i) VCDR with SNPs rs1900004 (ATOH7); rs1192415 (CDC7); rs10483727 (SIX1/SIX6), rs9607469 (CARD10); ii) CCT with rs1192415; iii) IOP with rs1900004 and iv) AL with rs1900004 and rs1063192 (CDKN2B). We were able to replicate previously known interactions between ATOH7-SIX6 and SIX6-CDKN2B along with few novel interactions between ATOH7-CDC7 and SIX6 with genes including CARD10 and CDC7. In summary, our results suggest that a probable interaction among the candidate genes for QTs, play a major role in determining the individual's susceptibility to POAG.

Purpose: To report the baseline risk factors and causes for incident blindness., Methods: Six years after the baseline study, 4419 subjects from the cohort underwent a detailed examination at the base hospital. Incident blindness was defined by World Health Organization criteria as visual acuity of less than 6/120 (3/60) and/or a visual field of less than 10° in the better-seeing eye at the 6-year follow-up, provided that the eye had a visual acuity of better than or equal to 6/120 (3/60) and visual field greater than 10° at baseline. For incident monocular blindness, both eyes should have visual acuity of more than 6/120 (3/60) at baseline and developed visual acuity of less than 6/120 (3/60) in one eye at 6-year follow-up., Results: For incident blindness, 21 participants (0.48%, 95% confidence interval [CI], 0.3-0.7) became blind; significant baseline risk factors were increasing age (P = 0.001), smokeless tobacco use (P < 0.001), and no history of cataract surgery (P = 0.02). Incident monocular blindness was found in 132 participants (3.8%, 95% CI, 3.7-3.8); it was significantly more (P < 0.001) in the rural population (5.4%, 95% CI, 5.4-5.5) than in the urban population (1.9%, 95% CI, 1.8-1.9). Baseline risk factors (P < 0.001) were increasing age and rural residence, and no history of cataract surgery was a protective factor (P = 0.03)., Conclusions: Increasing age was a significant risk factor for blindness and monocular blindness. No history of cataract surgery was a risk factor for blindness and a protective factor for monocular blindness., (Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.)

Aim: To evaluate the prevalence and causes of low vision and blindness in an urban south Indian population., Settings and Design: Population-based cross-sectional study. Exactly 3850 subjects aged 40 years and above from Chennai city were examined at a dedicated facility in the base hospital., Materials and Methods: All subjects had a complete ophthalmic examination that included best-corrected visual acuity. Low vision and blindness were defined using World Health Organization (WHO) criteria. The influence of age, gender, literacy, and occupation was assessed using multiple logistic regression., Statistical Analysis: Chi-square test, t-test, and multivariate analysis were used., Results: Of the 4800 enumerated subjects, 3850 subjects (1710 males, 2140 females) were examined (response rate, 80.2%). The prevalence of blindness was 0.85% (95% CI 0.6-1.1%) and was positively associated with age and illiteracy. Cataract was the leading cause (57.6%) and glaucoma was the second cause (16.7%) for blindness. The prevalence of low vision was 2.9% (95% CI 2.4-3.4%) and visual impairment (blindness + low vision) was 3.8% (95% CI 3.2-4.4%). The primary causes for low vision were refractive errors (68%) and cataract (22%)., Conclusions: In this urban population based study, cataract was the leading cause for blindness and refractive error was the main reason for low vision.

Purpose: To estimate the 6-year incidence of primary angle-closure (PAC) disease among adult population aged 40 years and older from rural and urban south India., Design: Population-based longitudinal study., Methods: A complete ophthalmologic examination, including applanation tonometry, gonioscopy, biometry, stereoscopic fundus examination, and automated perimetry was performed at both baseline and at the 6-year follow up at base hospital. Incident PAC disease was defined as the development of PAC disease during the 6-year follow-up in phakic subjects without PAC disease at baseline. Diagnosis was made using the International Society Geographical and Epidemiological Ophthalmology classification., Results: The data were analyzed for 3350 subjects (mean age, 56.4 ± 8.9 years; 1547 males, 1803 females) for a diagnosis of PAC disease at baseline and at follow-up examinations. The incidence of PAC disease was identified in 134 subjects (6-year incidence rate, 4.0%; 95% confidence interval (CI), 3.3-4.7). Among the 134 subjects, 88 subjects (2.6%, 95% CI, 2.1-3.2) were primary angle-closure suspects; 37 subjects (1.1%, 95% CI, 0.7-1.5) had primary angle closure, and 9 subjects (0.3%, 95% CI, 0.1-0.4) had primary angle-closure glaucoma. There was an inverse relationship between the incidence of PAC disease and the cataract surgery rates. Significant risk factors for PAC disease on logistic regressions were higher intraocular pressure, increased lens thickness, shorter axial length, shallow anterior chamber depth, anteriorly positioned lens, and hyperopia., Conclusions: The average incidence of PAC disease per year was 0.7%. All biometric parameters were found to be strong predictors for the incidence of PAC disease., (Copyright © 2013 Elsevier Inc. All rights reserved.)

The Western Ghats of Karnataka natural ecosystem are among the most diverse and is one of the eight hottest hotspots of biological diversity in the world, that runs along the western part of India through four states including Karnataka. Bacillus thuringiensis (Bt) strains were isolated from soils of Western Ghats of Karnataka and characterized by molecular and analytical methods as a result of which 28 new Bt-like isolates were identified. Bt strains were isolated from soil samples using sodium acetate selection method. The morphology of crystals was studied using light and phase contrast microscopy. Isolates were further characterized for insecticidal cry gene by PCR, composition of toxins in bacterial crystals by SDS-PAGE cloning, sequencing and evaluation of toxicity was done. As a result 28 new Bt-like isolates were identified. Majority of the isolates showed the presence of a 55 kDa protein bands on SDS-PAGE while the rest showed 130, 73, 34, and 25 kDa bands. PCR analysis revealed predominance of Coleopteran-active cry genes in these isolates. The variations in the nucleotide sequences, crystal morphology, and mass of crystal protein(s) purified from the Bt isolates revealed genetic and molecular diversity. Three strains containing Coleopteran-active cry genes showed higher activity against larvae Myllocerus undecimpustulatus undatus Marshall (Coleoptera: Curculionidae) than B. thuringiensis subsp. Morrisoni. Results indicated that Bt isolates could be utilized for bioinsecticide production, aiming to reduce the use of chemical insecticide which could be useful to use in integrated pest management to control agriculturally important pests for sustainable crop production.

Bemisia tabaci is the major vector pest of agricultural crops all over the world. In this study we report the different bacterial endosymbionts associated with B. tabaci sampled from 14 different locations in North India. Using 16S rDNA clone library sequences we were able to identify Portiera, the primary endosymbiont of B. tabaci, and other secondary endosymbionts like Cardinium, Wolbachia, Rickettsia and Arsenophonus. Along with these we also detected Bacillus, Enterobacter, Paracoccus and Acinetobacter. These secondary endosymbionts were not uniformly distributed in all the locations. Phylogenetic analysis of 16S rDNA sequences of Cardinium, Wolbachia, Rickettsia and Arsenophonus showed that each of these bacteria form a separate cluster when compared to their respective counterparts from other parts of the world. MtCO1 gene based phylogenetic analysis showed the presence of Asia I and Asia II genetic groups of B. tabaci in N. India. The multiple correspondence analyses showed no correlation between the host genetic group and the endosymbiont diversity. These results suggest that the bacterial endosymbiont diversity of B. tabaci is much larger and complex than previously perceived and probably N. Indian strains of the bacterial symbionts could have evolved from some other ancestor., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Purpose: To describe the prevalence and factors associated with pterygium and pinguecula in a south Indian population., Methods: The Chennai Glaucoma Study examined 7774 (Urban 3850, Rural 3924) subjects aged above 40 years. All subjects underwent a comprehensive ophthalmic evaluation. Personal history, occupation and lifetime ultraviolet exposure were documented. The presence of pterygium and pinguecula on slit-lamp examination was recorded. The prevalence of pterygium and pinguecula, differences in the rural and urban populations and their association with age, gender, residence, nature of occupation, lifetime ultraviolet radiation exposure, tobacco use (smoking/smokeless), alcohol use, diabetes mellitus and hypertension were analyzed., Results: The mean age of the subjects was 54.6 (SD: 10.6) years. Pterygium was present in either eye of 740 subjects (9.5%, 95% CI: 8.6-10.4%), of which 329 subjects were male and 411 subjects were female. The prevalence of pterygium differed significantly (OR: 4.60 95% CI: 3.82-5.56, p < 0.0001) between the urban (144, 3.7%, 95% CI: 3.1-4.3%) and the rural population (596, 15.2%, 95% CI: 14.1-16.3%). Pinguecula was present in either eye of 875 subjects (11.3%, 95% CI: 10.5-12.0%), of which 368 subjects were male and 507 subjects were female. The prevalence of pinguecula differed significantly (OR: 2.94, 95% CI: 2.51-3.43, p < 0.0001) between the urban (238, 6.2%, 95% CI: 5.4-6.9%) and the rural population (637, 16.2%, 95% CI: 15.1-17.4%). Pinguecula and pterygium were significantly associated with rural residence (p < 0.0001). We found rural residence and exposure to higher lifetime UV exposure to be significantly associated with the presence of pterygium (p < 0.0001). Non-use of spectacles was found to be associated with both pterygium (OR: 1.41, 95% CI: 1.12-1.79) and pinguecula (OR: 1.69, 95% CI: 1.38-2.08). The presence of pterygium and pinguecula was not associated with smoking, use of alcohol, nature of work, diabetes and hypertension., Conclusion: The prevalence of pterygium and pinguecula a South Indian population were 9.5% and 11.3% respectively. Rural residence were associated with presence of both pterygium and pinguecula. Higher lifetime UV exposure was associated with the presence of pterygia., (Ophthalmic & Physiological Optics © 2011 The College of Optometrists.)

In the last decade, there have been reports on the prevalence of glaucoma from the Vellore Eye Survey, Andhra Pradesh Eye Diseases Survey, Aravind Comprehensive Eye Survey, Chennai Glaucoma Study and West Bengal Glaucoma Study. Population-based studies provide important information regarding the prevalence and risk factors for glaucoma. They also highlight regional differences in the prevalence of various types of glaucoma. It is possible to gather important insights regarding the number of persons affected with glaucoma and the proportion with undiagnosed disease. We reviewed the different population-based studies from India and compare their findings. The lacunae in ophthalmic care that can be inferred from these studies are identified and possible reasons and solutions are discussed. We also discuss the clinical relevance of the various findings, and how it reflects on clinical practice in the country. Since India has a significantly high disease burden, we examine the possibility of population-based screening for disease in the Indian context.

Dengue fever and dengue haemorrhagic fever (DF/DHF) have become a serious public health problem in many parts of India in recent years. Several vertical national programmes for communicable diseases, which include vector-borne diseases such as malaria and filariasis have been in operation for over five decades in India. The remarkable increase in dengue fever and DHF related deaths during the last decade has necessitated an effective surveillance system to detect the cases and adopt appropriate control measures against dengue vectors. Although the existence of all the four serotypes of dengue virus was proved as early as in 1960s, it was only after 1990, several outbreaks of DF/DHF were reported in Tamil Nadu. Further, dengue, once considered as urban problem has now penetrated into rural areas also, due to various changes in the environment. The geographic spread, increase in number of cases, reporting system, laboratory diagnosis, monitoring of vector density and investigation of outbreaks in Tamil Nadu during the last decade are comprehensively documented and discussed here to further strengthen the surveillance network to prevent possible major outbreaks of DF/DHF.