Automated Brain Tumor Detection using Ideal Shallow Neural Network with Artificial Jellyfish Optimization.

INTRODUCTION: Brain tumors are predicted from Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) scan images. In recent years, image processing-based automated tools are developed to predict tumor areas with less human interference. However, such automated tools are suffering from computational complexity and reduced accuracy in certain critical images. In the proposed work, an Ideal Shallow Neural Network (ISNN) is utilized to improve the prediction accuracy, and the computational complexity is reduced by implementing an Artificial Jellyfish Optimization (AJO) algorithm for minimizing the feature dimensionality. METHOD: The proposed method utilizes MRI images for the verification process as they are more informative than the CT scan image. The BRATS and the Kaggle datasets are used in this work and a Gabor filtering technique is used for noise reduction and a histogram equalization is used for enhancing the tumor boundary regions. The classification results observed from the AJO-ISNN are further forwarded towards the segmentation process and which uses the Centroid Weighted Segmentation (WCS) along with a Grasshopper Optimization Algorithm (GOA) for improving the segmentation over the boundary regions of the brain tumor. RESULT: The experimental result indicates a classification accuracy of 95.14% on the proposed AJO-ISNN model and AJO-ISNN is comparatively better than the Convolutional Neural Network (CNN) model accuracy of 85.41% and VGG 19 model accuracy of 93.75% while implemented with the AJO optimization model. Similarly, the Dice Similarity Coefficient of the proposed CWS-GOA also reaches 93.15% when performed with both BRATS and Kaggle datasets. CONCLUSION: Apart from the accuracy attainments the proposed work classifies and segments the tumor region in around 65 seconds on average of 200 image verifications and that is comparatively better than the previous multi-cascaded CNN and the InceptionV3 models.

Molecular characterization of the Indian isolate (Ka-To) of tomato spotted wilt virus (TSWV) infecting tomato (Solanum lycopersicum L.).

Tomato spotted wilt virus (TSWV) infecting tomato has been identified as an emerging constraint for tomato cultivation in the southern Indian states of Karnataka and Tamil Nadu. Infection of TSWV produces circular necrotic ring spots on leaves, stem and floral necrosis and necrotic ringspots on fruits of tomato. In this study, we describe the characterization of TSWV isolate (Ka-To) infecting tomato from India based on biological, serological and molecular assay. Pathogenicity of TSWV (Ka-To) isolate was established by mechanical inoculation of sap from infected leaves on tomato, cowpea and datura which expressed necrotic or chlorotic local lesions. Samples were tested positive in the serological assay performed with TSWV-specific immunostrips. Further, reverse transcription polymerase chain reaction (RT-PCR) amplification of coat protein gene followed by sequencing, unequivocally confirmed the identity of TSWV. The obtained full-length nucleotide sequences of Ka-To isolate [L RNA-MK977648; M RNA-MK977649; and S RNA-MK977650] had greater similarity to the TSWV isolates of Spain and Hungary infecting tomato and pepper. The phylogenetic and recombination analysis showed the evidence for reassortment and recombination in the genome of Ka-To isolate. To the best of our knowledge, this is the first confirmed evidence for the occurrence of TSWV on tomato in India. Information obtained in this study issues a forewarning on the emergence of TSWV on vegetable ecosystem in the Indian subcontinent, requiring urgent management strategies to curtail its pestilence. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03579-y.

Evidence-based insecticide resistance in South American tomato leaf miner, Phthorimaea absoluta (Meyrick) under laboratory selection.

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.

The evolutionary process of invasion in the fall armyworm (Spodoptera frugiperda).

The fall armyworm (FAW; Spodoptera frugiperda) is one of the major agricultural pest insects. FAW is native to the Americas, and its invasion was first reported in West Africa in 2016. Then it quickly spread through Africa, Asia, and Oceania, becoming one of the main threats to corn production. We analyzed whole genome sequences of 177 FAW individuals from 12 locations on four continents to infer evolutionary processes of invasion. Principal component analysis from the TPI gene and whole genome sequences shows that invasive FAW populations originated from the corn strain. Ancestry coefficient and phylogenetic analyses from the nuclear genome indicate that invasive populations are derived from a single ancestry, distinct from native populations, while the mitochondrial phylogenetic tree supports the hypothesis of multiple introductions. Adaptive evolution specific to invasive populations was observed in detoxification, chemosensory, and digestion genes. We concluded that extant invasive FAW populations originated from the corn strain with potential contributions of adaptive evolution.

Genome Mining and Expression Analysis of Carboxylesterase and Glutathione S-Transferase Genes Involved in Insecticide Resistance in Eggplant Shoot and Fruit Borer, Leucinodes orbonalis (Lepidoptera: Crambidae).

The shoot and fruit borer, Leucinodes orbonalis (Lepidoptera: Crambidae) is the major cause of low productivity in eggplant and insecticides being the mainstay of management of L. orbonalis. However, field control failures are widespread due to the evolution of insecticide resistance. Taking advantage of the whole genome sequence information, the present study investigated the level of insecticide resistance and the expression pattern of individual carboxylesterase (CE) and glutathione S-transferases (GSTs) genes in various field collected populations of L. orbonalis. Dose-mortality bioassays revealed a very high level of resistance development against fenvalerate (48.2-160-fold), phosalone (94-534.6-fold), emamectin benzoate (7.2-55-fold), thiodicarb (9.64-22.7-fold), flubendiamide (187.4-303.0-fold), and chlorantraniliprole (1.6-8.6-fold) in field populations as compared to laboratory-reared susceptible iso-female colony (Lo-S). Over-production of detoxification enzymes viz., CE and GST were evident upon enzyme assays. Mining of the draft genome of L. orbonalis yielded large number of genes potentially belonging to the CE and GST gene families with known history of insecticide resistance in other insects. Subsequent RT-qPCR studies on relative contribution of individual genes revealed over-expression of numerous GSTs and few CEs in field populations, indicating their possible involvement of metabolic enzymes in insecticide resistance. The genomic information will facilitate the development of novel resistance management strategies against this pest.

Modeling Commodity Flow in the Context of Invasive Species Spread: Study of Tuta absoluta in Nepal.

Trade and transport of goods is widely accepted as a primary pathway for the introduction and dispersal of invasive species. However, understanding commodity flows remains a challenge owing to its complex nature, unavailability of quality data, and lack of systematic modeling methods. A robust network-based approach is proposed to model seasonal flow of agricultural produce and examine its role in pest spread. It is applied to study the spread of Tuta absoluta, a devastating pest of tomato in Nepal. Further, the long-term establishment potential of the pest and its economic impact on the country are assessed. Our analysis indicates that regional trade plays an important role in the spread of T. absoluta. The economic impact of this invasion could range from USD 17-25 million. The proposed approach is generic and particularly suited for data-poor scenarios.

Screening of a multi-virus resistant RNAi construct in cowpea through transient vacuum infiltration method.

Plant viruses are the most devastating pathogens causing substantial economic losses in many crops. Current viral disease management relies on prophylactics, roguing and insect vector control, since in most crops resistant gene pools for resistance breeding are unavailable. RNA interference, a sequence dependent gene silencing mechanism holds great potential in imparting virus resistance. In this study, the efficacy of a RNAi gene construct developed against four viruses commonly infesting tomato and chilli viz., capsicum chlorosis virus, groundnut bud necrosis virus, cucumber mosaic virus and chilli veinal mottle virus was evaluated. A 3546 bp dsRNA-forming construct comprising sense-intron-antisense fragments in binary vector pBI121 (hpRNAi-MVR) was mobilized into Agrobacterium tumefaciens. Cowpea (Vigna unguiculata) was used as an indicator plant for GBNV agroinfiltration to evaluate the efficacy of hpRNAi-MVR construct in conferring GBNV resistance. The type of agroinfiltration, bacterial concentration and incubation-temperatures were optimized. Vacuum infiltration of three pulses of 20-30 s at 66.66 kPa were effective than syringe infiltration. Of the five Agrobacterial concentrations, OD600 0.5 was more efficient. Incubation temperature of 31 ± 1 °C was favorable for development of disease symptoms than 20 ± 1 °C and 26 ± 1 °C. ELISA revealed a 35% decline in viral load in hpRNAi-MVR infiltrated plants compared to vector control plants. Quantitative real time PCR results have shown a viral gene silencing to the extent of 930-990 folds in hpRNAi-MVR infiltrated plants compared to vector control. This approach is simple, rapid and efficient to screen the efficacy of RNAi constructs developed for the RNAi mediated plant virus management.

Genetic characterization of fall armyworm infesting South Africa and India indicate recent introduction from a common source population.

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.

Double-Stranded RNA-Mediated Suppression of Trypsin-Like Serine Protease (t-SP) Triggers Over-Expression of Another t-SP Isoform in Helicoverpa armigera.

High diversity of digestive proteases is considered to be the key factor in the evolution of polyphagy in Helicoverpa armigera. Serine proteases (SPs) contribute ~85% of the dietary protein digestion in H. armigera. We investigated the dynamics of SP regulation in the polyphagous pest, H. armigera using RNA interference (RNAi). HaTry1, an isoform of SP, expressed irrespective of the composition of the diet, and its expression levels were directly proportional to the larval growth rate. Therefore, HaTry1 was silenced by delivering 10 and 20 µg concentrations of double-stranded RNA through semi-synthetic diet. This led to a drastic reduction in the target gene transcript levels that manifested in a significant reduction in the larval weight initially, but the larvae recovered in later stages despite continuous dsRNA treatment. This was probably due to the compensatory effect by over-expression of HaTry13 (31-folds), another isoform of SP. Phylogenetic analysis of H. armigera SPs revealed that the over-expressed isoform was closely related to the target gene as compared to the other tested isoforms. Further, silencing of both the isoforms (HaTry1 and HaTry13) caused the highest reduction in the larval weight and there was no larval growth recovery. These findings provide a new evidence of the existence of compensatory effect to overcome the effect of silencing individual gene with RNAi. Hence, the study emphasizes the need for simultaneous silencing of multiple isoforms.

Development of a test grid using Eye Movement Perimetry for screening glaucomatous visual field defects.

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/m2 and 190 cd/m2 on a background of 140 cd/m2) 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/ m2. 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.

Heteroplasmy due to coexistence of mtCOI haplotypes from different lineages of the Thrips tabaci cryptic species group.

Heteroplasmy is the existence of multiple mitochondrial DNA haplotypes within the cell. Although the number of reports of heteroplasmy is increasing for arthropods, the occurrence, number of variants, and origins are not well studied. In this research, the occurrence of heteroplasmy was investigated in Thrips tabaci, a putative species complex whose lineages can be distinguished by their mitochondrial DNA haplotypes. The results from this study showed that heteroplasmy was due to the occurrence of mitochondrial cytochrome oxydase I (mtCOI) haplotypes from two different T. tabaci lineages. An assay using flow cytometry and quantitative real-time PCR was then used to quantify the per cell copy number of the two mtCOI haplotypes present in individuals exhibiting heteroplasmy from nine geographically distant populations in India. All of the T. tabaci individuals in this study were found to exhibit heteroplasmy, and in every individual the per cell copy number of mtCOI from lineage 3 comprised 75-98% of the haplotypes detected and was variable among individuals tested. There was no evidence to suggest that the presense of lineage-specific haplotypes was due to nuclear introgression; however, further studies are needed to investigate nuclear introgression and paternal leakage during rare interbreeding between individuals from lineages 2 and 3.

TB management by private practitioners - Is it bad everywhere?

INTRODUCTION: Poor prescribing practice is alleged to be one of the major factors fuelling the drug-resistant tuberculosis (DR TB) emergence. A study in Mumbai revealed the extent of inappropriate tuberculosis (TB) management practices of private practitioners and discussed that with the context of high DR TB. Kerala is rated among the well performing States in India as far as TB control is concerned with evidences for a lower level of TB transmission and DR TB. The current study was done in Kerala State to assess the prescribing practices of private sector doctors in the treatment of TB. METHODS: Survey questionnaire to write a standard prescription for treating TB was administered to private practitioners dealing with TB, who attended continuing medical education programme on TB at two major cities in Kerala. RESULTS: Responses from a total of 124 questionnaires were studied. None of them prescribed anti-TB regimen for less than 6 months. Only 7 (5.6%) prescribed a regimen without complete four drugs (H, R, Z, E) in the intensive phase. Out of the 81 doctors who prescribed private anti-TB regimen, 67 (82.7%) had of the opinion that not less than 80% of their patients complete the treatment for the prescribed duration. CONCLUSION: The current study reports a reasonable TB management practice among the private sector doctors from a State with a low prevalence of DR TB and compliments the argument that effective treatment of TB following the principles of standards for TB care can prevent the emergence of DR TB.

The First Report of miRNAs from a Thysanopteran Insect, Thrips palmi Karny Using High-Throughput Sequencing.

Thrips palmi Karny (Thysanoptera: Thripidae) is the sole vector of Watermelon bud necrosis tospovirus, where the crop loss has been estimated to be around USD 50 million annually. Chemical insecticides are of limited use in the management of T. palmi due to the thigmokinetic behaviour and development of high levels of resistance to insecticides. There is an urgent need to find out an effective futuristic management strategy, where the small RNAs especially microRNAs hold great promise as a key player in the growth and development. miRNAs are a class of short non-coding RNAs involved in regulation of gene expression either by mRNA cleavage or by translational repression. We identified and characterized a total of 77 miRNAs from T. palmi using high-throughput deep sequencing. Functional classifications of the targets for these miRNAs revealed that majority of them are involved in the regulation of transcription and translation, nucleotide binding and signal transduction. We have also validated few of these miRNAs employing stem-loop RT-PCR, qRT-PCR and Northern blot. The present study not only provides an in-depth understanding of the biological and physiological roles of miRNAs in governing gene expression but may also lead as an invaluable tool for the management of thysanopteran insects in the future.

Insilco Prediction and Characterization of microRNAs from Oncopeltus fasciatus (Hemiptera: Lygaeidae) Genome.

For studies on functional genomics, small RNAs, especially microRNAs (miRNAs), have emerged as a hot topic due to their importance in cellular and developmental processes. Identification of insect miRNAs largely depends on the availability of genomic sequences in the public domain. The large milkweed bug, Oncopeltus fasciatus (Dallas) is a hemimetabolous insect which has become a model hemipteran system for various molecular studies. In this study, we identified 96 candidate mature miRNAs from O. fasciatus genome using a blast search with the previously reported animal miRNAs. The secondary structure of predicted miRNA sequences was determined online using "mfold" web server and verified by calculating the minimal free energy index (MFEI). Six miRNAs let-7e, miR-133c, miR-219b, mir-466d, mir-669f, and mir-669l are reported for the first time in Insecta. Comparison of O. fasciatus mir-2 and mir-71 family clusters to those of diverse insect species showed that they are highly conserved. The phylogenetic analysis of miRNAs revealed the evolutionary relationship of conserved miRNAs of O. fasciatus with other insect species. Using a classical rule-based algorithm method, we predicted the possible targets of the new miRNAs. Our study not only identified the list of miRNAs in O. fasciatus but also provides a basic platform for developing novel pest management strategies based on artificial miRNAs.

Diet-delivered RNAi in Helicoverpa armigera--Progresses and challenges.

Helicoverpa armigera (the cotton bollworm) is a significant agricultural pest endemic to Afro-Eurasia and Oceania. Gene suppression via RNA interference (RNAi) presents a potential avenue for management of the pest, which is highly resistant to traditional insecticide sprays. This article reviews current understanding on the fate of ingested double-stranded RNA in H. armigera. Existing in vivo studies on diet-delivered RNAi and their effects are summarized and followed by a discussion on the factors and hurdles affecting the efficacy of diet-delivered RNAi in H. armigera.

RNA Interference of Odorant-Binding Protein 2 (OBP2) of the Cotton Aphid, Aphis gossypii (Glover), Resulted in Altered Electrophysiological Responses.

Aphis gossypii (Glover) (Hemiptera: Aphididae) is a highly invasive pest that feeds primarily on phloem resulting in severe economic loss to growers. A. gossypii has cosmopolitan distribution with broad host range, polyphenism, parthenogenetic mode of reproduction, vectoring abilities, and host alteration which has profound influence on its management. Odorant-binding proteins (OBPs) in insects are involved in olfaction, playing a key role in orienting the insect for feeding or oviposition. Recent studies revealed that OBP2 is found in both sensilla trichodea and sensilla basiconica and is preferentially binds to plant volatiles, thus playing crucial roles in host-seeking, detection of oviposition attractants, etc., However, information about the role of OBP2 in A. gossypii (AgOBP2) is still unavailable. In this study, we cloned and characterized OBP2, ortholog from A. gossypii, and the full-length AgOBP2 complementary DNA (cDNA) consisted of 859 bp with an open reading frame of 732 bp. Phylogenetic analysis resulted in grouping of AgOBP2 protein with members of the tribe Aphidini. Further, diet-mediated delivery of double-stranded RNA for AgOBP2 induced silencing, which was evaluated at 48 and 96 h. The reverse transcriptase real-time quantitative polymerase chain reaction (RTq-PCR) results revealed that the level of AgOBP2 messenger RNA (mRNA) was significantly reduced (55-77 %) in dsAgOBP2 treatment after 96 h as compared to the untreated control. The same was reiterated by the electrophysiological responses in the aphids which was reduced (>50 % at 0.25 µg/µl concentration) as compared to the untreated control. Thus, our results showed the potential of gene silencing, possibly to interfere with the odorant perception of A. gossypii for RNAi-mediated pest management. The results from our study provided the first evidence that AgOBP2 play crucial roles in host-seeking, detection of oviposition attractants, etc.; as a result, we suggests that OBP2 could potentially serve as a practicable target for RNAi-mediated gene silencing in hemipteran insect pest control.

Diet-Delivered dsRNAs for Juvenile Hormone-Binding Protein and Vacuolar ATPase-H Implied Their Potential in the Management of the Melon Aphid (Hemiptera: Aphididae).

RNA interference is a sequence-specific gene silencing mechanism mediated by double-stranded RNA (dsRNA), which has been harnessed as a useful tool in devising novel insect pest management strategies for various pests such as melon aphid, Aphis gossypii (Glover). In the current study, we cloned and sequenced juvenile hormone-binding protein (JHBP) and vacuolar ATPase subunit H (V-ATPase-H) from A. gossypii. We also showed the effectiveness of diet-mediated delivery of dsRNA for JHBP and V-ATPase-H, which silenced the above genes and resulted in mortality. The extent of silencing and mortality were similar for both genes up until 96 h. Bioassay results revealed that the target genes were silenced variably, 1.0 µg/µl concentration having a more profound effect than 0.5 and 0.25 µg/µl concentration in reducing the cognate mRNA transcript level. Results indicated a 9.56­73.21% down regulation (across time and concentrations for both the genes) that resulted in the mortality of A. gossypii. Mortality was in the range of 10­63% for both these genes. Thus, the current study demonstrated the potentiality of both JHBP and V-ATPase-H as excellent targets for the management of A. gossypii.

Distribution of Bemisia tabaci Genetic Groups in India.

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.

Sequence analysis of Indian iris yellow spot virus ambisense genome segments: evidence of interspecies RNA recombination.

The nucleotide sequence of M- and S-RNA segments of an Indian iris yellow spot virus (IYSV) were determined. Sequence comparisons showed that both of these sequences shared less than 95 % identity with those other known IYSV isolates. Phylogenetic analysis revealed that the S- and M-RNA sequences of known IYSV isolates clustered with those of the tospoviruses, tomato yellow ring virus, polygonum ringspot virus and hippeastrum chlorotic ringspot virus. Further, multiple recombination detection methods detected inter- and intra-species recombination events that clustered primarily within the intergenic regions of S- and M-RNA, suggesting that these are possibly recombination hotspots in IYSV and closely related tospoviruses.