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The influence of environmental parameters on the development of powdery mildew caused by Oidium mangiferae Berthet on mango inflorescence was studied for seven consecutive years (2012-18) in humid tropics climatic conditions of South Gujarat. The disease incidence and severity (DIS), area under disease progress curve-AUDPC (A-value) and apparent infection rate (r-value) were recorded at panicle and fruit setting stages of the tree at weekly intervals. The correlation studies showed that incidence and severity of powdery mildew significantly negative relationship with morning relative humidity (r = -0.631; p

Maximum entropy (MaxEnt) modeling was used to predict impact of climate change on habitat suitability of guava fruit fly, Bactrocera correcta in India. It is a polyphagus pest on a wide variety of fruit crops. Future prediction of potential habitat of B.correcta was done for the year 2050 and 2070 with RCP 2.6, RCP 4.5, RCP 6.0 and RCP 8.5 climate scenarios. The model preformed better than random with an average test AUC value of 0.75 of 100 replicate tests run. Under the present and future climatic conditions, the model predicted high habitat suitable category for B. correcta in the areas of south-western coastal (Kerala, Karnataka, Tamilnadu, Maharashtra and Gujarat) part of India by 2050 and 2070. Presently absolute unsuitable areas of Indian sub-continent are projected to be slightly suitable for B. correcta by 2070 due to increase in temperature coupled with decrease in cold stress. The predictive modeling approach presented here provides an outline for future risk of B.correcta in India under climate change scenarios, which can be used for its better management strategies.

Mango hopper, Idioscopus nitidulus is the most destructive pest of mango in the India. Thus, aim of the study was to develop precise and easy early population prediction model of mango hopper for tropical mansoon climate conditions. Weekly occurrence data of mango hopper, I. nitidulus during five consecutive years (2014 to 2018) was used for developing hybrid of multiplicative seasonal autoregressive integrated moving average (SARIMA) and artificial neural network (ANN) model. The population of I. nitidulus increases in the month of January-February on flower panicles and October-November on new vegetative shoots in the region. The linearity in the time series data was best fitted with SARIMA (0, 0, 2) × (0, 1, 1)52 model as their correlation values are not outside the confidence intervals (CI) limits. Further ANN modeling was done for fitting the SARIMA residuals. The fitted values of model prediction and the actual values of year 2017-2018 flowering season (SMW36-52 of 2017 and SMW 1-13 of 2018) were used for testing of prediction efficiency. The performance of the two models in respect to model fitting and effectiveness of SARIMA and hybrid SARIMA-ANN model was compared by evaluating diagnostic statistics of MSE, RMSE, MAE and MAPE. The best fitted developed hybrid model in present study and the data predicted by model was matched with actual data of mango hopper incidence during the year 2017-18. Hybrid model developed in this study will help to predict hoppers population in advance, thus provide a direction for planning of timely prevention and development of effective management strategies which will help to minimize the use of hazardous pesticides.

Fall armyworm,Spodoptera frugiperda(J. E. Smith) is a polyphagous and highly destructive invasive insect pest of many crops. It was recently introduced into India and widely reported in almost all parts of India. Development of a temperature-based phenology model for predicting its rate of development and distribution will help in understanding the establishment and further spread of introduced invasive insect pests. Development, survival and reproduction parameters ofS. frugiperdaat six constant temperature conditions (15, 20, 25, 27, 30 and 35°C) were investigated and further validated with data generated under fluctuating temperature conditions. The estimated lower developmental threshold temperatures were 12.1°C for eggs, 11°C for larvae, 12.2°C for pupae, 15.13°C for males and 12.66°C for females. Degree-day (DD) requirements for the development of the different stages ofS. frugiperdawere 50, 250 and 200 DD for egg, larva and pupa, respectively. The best-fitted functions were compiled for each life stage to yield a phenology model, which was stochastically simulated to estimate the life table parameters. The developed phenology model predicted temperature ranges between 27 and 30°C as favourable forS. frugiperdadevelopment, survival and reproduction. The results revealed that maximum net reproductive rate (215.66 females/female/generation) and total fecundity (981.08 individuals/female/generation) were attained at 30°C constant temperature. The mean length of generations decreased from 74.29 days at 15°C to 38.74 days at 30°C. The maximum intrinsic rate of increase (0.138 females/female/day) and shortest doubling time (4.9 days) were also observed at 30°C. Results of simulated life table parameters showed high temperature-dependent development ofS. frugiperdaand complete development within all the tested constant temperature ranges (15–35°C). Simulated life table parameters for predicting risk indices ofS. frugiperdain India indicated a significant increase in activity indices and establishment risk indices with a higher number of generations during future (2050 and 2070) climatic change scenarios compared to present conditions. Our results indicate that India will be highly suitable for the establishment and survival ofS. frugiperdain future time periods.

The next generation sequencing (NGS) approach has facilitated the investigations of gut microbiota with high throughput and resolution. The present study was focused on the taxonomic and functional characterization of bacterial community associated with different developmental stages of melon fly, Zeugodacus cucurbitae using 16S ribosomal RNA (rRNA) gene amplicons metagenomics. Z. cucurbitae is considered an invasive and most staid polyphagous pest of cucurbitaceous and other related crops. The taxonomic analysis of highly variable V3–V4 region of bacterial 16S rRNA gene sequencing indicated that the bacterial community associated with Z. cucurbitae consists of a total of 23 bacterial phyla (including unclassified and unassigned bacteria), comprising 32 classes, 69 orders, 99 families and 130 genera. Proteobacteria, Firmicutes, Actinobacteria and Tenericutes were dominant phyla of which family, Enterobacteriaceae was the most abundant in the larval and adult female stages, whereas Mycoplasmataceae was the dominant in the pupal stage. In larval stages of Z. cucurbitae, genus Providencia and Comamonas were the most abundant. However, genus Candidatus-Bacilloplasma and Klebsiella were the most dominant in pupae and adult females of Z. cucurbitae, respectively. PICRUSt analysis conducted for prediction of metabolic activities revealed that associated microbiota were involved in membrane transport, carbohydrate metabolism, amino acid metabolism, energy metabolism, replication and repair processes as well as cellular processes and signalling. The higher number of OTUs was annotated for phosphoglycerate mutase and transketolase in adult females followed by larval stages, which may support the digestive function of the microbiota in larvae and adult females. Our findings provide insights about the high variation in microbiota across developmental stages and basis for microbiota-based management strategies of fruit flies.

Onion is the most important crop challenged by a diverse group of insect pests in the agricultural ecosystem. The green semilooper (Chrysodeixis acuta Walker), a widespread tomato and soybean pest, has lately been described as an emergent onion crop pest in India. C. acuta whole mitochondrial genome was sequenced in this work. The circular genome of C. acuta measured 15,743 base pairs (bp) in length. Thirteen protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and one control region were found in the 37 sequence elements. With an average 395 bp gene length, the maximum and minimum gene length observed was 1749 bp and 63 bp of nad5 and trnR, respectively. Nine of the thirteen PCGs have (ATN) as a stop codon, while the other four have a single (T) as a stop codon. Except for trnS1, all of the tRNAs were capable of producing a conventional clover leaf structure. Conserved ATAGA motif sequences and poly-T stretch were identified at the start of the control region. Six overlapping areas and 18 intergenic spacer regions were found, with sizes ranged from 1 to 20 bp and 1 to 111 bp correspondingly. Phylogenetically, C. acuta belongs to the Plusiinae subfamily of the Noctuidae superfamily, and is closely linked to Trichoplusia ni species from the same subfamily. In the present study, the emerging onion pest C. acuta has its complete mitochondrial genome sequenced for the first time.

Mexican beetle, Zygogramma bicolorata Pallister (Coleptera: Chrysomelidae) is a potential weed control biocontrol agent in Australia, India and other countries. Its grubs and adults feed on the leaves of parthenium weed, Parthenium hysterophorus and check the further growth of the plant. Experiments were conducted to understand host plant-mediated effects of elevated temperature and elevated CO2 on biocontrol agent Z. bicolorata. Food consumption, utilization, ecological efficiency and life-table parameters of Z. bicolorata were studied in grubs and adults stage up to diapause. Reduction of leaf nitrogen in parthenium weed foliage with a significant increase in carbon and C:N ratio was recorded at elevated CO2. Elevated CO2 and temperature had no effect on adult longevity before diapausing. Duration of egg's hatching, specific stages of grub and pupa of Z. bicolorata were significantly longer when beetles fed on leaves grown under elevated CO2 but these parameters decreased significantly on leaves grown under elevated temperature. Significantly high consumption rates with low growth and digestion conversions were observed under elevated CO2 and/or in coupled with elevated temperature. Elevated CO2 and temperature-grown parthenium weed foliage also had a significant effect on Z. bicolorata intrinsic rate of increase (R), finite rate of increase (λ), mean generation time (T), and gross reproductive rate. Changed quality of parthenium weed leaves in elevated CO2 and temperature levels resulted in the increase of consumption, slower food conversion rates, increase in developmental period with reduced reproduction efficiency of Z. bicolorata. Our results indicate that the reproduction efficiency of Z. bicolorata is likely to be reduced as the climate changes, despite increased feeding rates exhibited by grubs and adult beetles on parthenium weed foliage.

Presently, rice-fallows are targeted for cropping intensification in South Asia. Rice-fallows a rainfed mono-cropping system remain fallow after rice due to lack of irrigation facilities and poor socio-economic condition of the farmers. Nevertheless, there is the scope of including ecologically adaptable winter crops in water-limited rice-fallow conditions with effective moisture conservation practices. The study aimed to identify the winter-crops that are adaptable and productive in rice-fallow conditions and to evaluate the different tillage-based crop establishment practices for soil moisture conservation, grain yield, economics, and sustainability parameters. Six different crop establishment and residue management (CERM) practices viz., zero-tillage direct seeded rice (ZTDSR), zero-tillage transplanted rice (ZTTPR), puddled transplanted rice (PTR), ZTDSR with rice residue retention (ZTDSRR+), ZTTPR with rice residue retention (ZTTPRR+), PTR with rice residue retention (PTRR+) as main-plot treatment and five winter crops (chickpea, lentil, safflower, linseed, and mustard) as sub-plot treatment were evaluated in a split-plot design. The productivity of grain legumes (chickpea and lentil) was higher over oilseed crops in rice-fallow conditions with an order of chickpea > lentil > safflower > mustard > linseed. Among the CERM practices, ZTDSRR+ and ZTDSR treatments increased the grain yield of all the winter crops over PTR treatment, which was primarily attributed to higher soil moisture retention for an extended period. Grain yield increment with conservation tillage practices was highly prominent in safflower (190%) followed by lentil (93%) and chickpea (70%). Rice grain yield was higher (7–35%) under PTR treatment followed by ZTDSR treatment. Conservation tillage practices (ZTDSR, ZTTPR) reduced energy use (11–20%) and increased the energy ratio over conventional tillage practice (PTR), higher in rice-safflower, rice-lentil and rice-chickpea rotations. Higher net return was attained in rice-safflower and rice-chickpea rotations with ZTDSRR+ treatment. Predicted emission of greenhouse gases was markedly reduced in ZTDSR treatment (30%) compared to ZTTPR and PTR treatments. Hence, the study suggests that cropping intensification of rice-fallows with the inclusion of winter crops like chickpea, lentil, and safflower following conservation tillage practices (ZTDSRR+ in particular) could be the strategic options for achieving the higher system productivity, economic returns, and energy use efficiency with the reduced emission of greenhouse gases.

Bactrocera zonata (Saunders), a serious polyphagous pest of horticultural crops, was studied for temperature based growth potential at ecologically relevant constant temperatures (15, 20, 25, 30 and 35 °C; relative humidity of 60 ± 10% and a photoperiod of 12:12 h L:D) and simulated growth potential parameters were validated with fluctuating temperatures life cycle data under laboratory conditions on artificial diet. Rate summation and cohort updating approaches were used for simulating development and estimating life-table parameters of B. zonata. The results revealed that lower development thresholds as 11.9, 12.7, and 13.6 °C and optimum temperature for survival as 26.01 °C, 26.2 °C and 25.5 °C determined for eggs, larvae and pupae, respectively. Reduction in mean development time of all immature stages occurred with increase in temperature. The highest net reproductive rate (77.64 ± 2.59 females/female/generation), total fecundity (260.20 ± 6.37 individuals/female/generation), intrinsic rate of increase (0.10 ± 0.000 females/female/day) and finite rate of increase (1.10 ± 0.000 females/female/day) were obtained maximum at 30 °C. At lowest extreme temperature (15 °C) tested in present study, females were not able to lay eggs. The temperature between 25 and 28 °C was the most suitable range for B. zonata reproduction and development. This shows that temperature has significant role in determining the climatic suitability for B. zonata in reproduction.

Fruit flies are the most serious economic insect pests of mango in India and other parts of the world. Under future climate change, shifts in temperature will be a key driver of ecosystem function especially in terms of insect pest dynamics. In this study, we predicted the voltinism of the three economically important fruit fly species viz., Bactrocera dorsalis (Hendel), Bactrocera correcta (Bezzi) and Bactrocera zonata (Saunders) of mango from 10 geographical locations in India using well established degree day approaches. Daily minimum and maximum temperature data were generated by using seven General Circulation Models (GCMs) along with their ensemble, in conjunction with the four representative concentration pathways (RCPs) scenarios (RCP 2.6, RCP 4.5, RCP 6.0 and RCP 8.5) and three time periods (2020, 2050 and 2080) generated from MarkSim® DSSAT weather file generator. Historical data from 1969–2005 of these 10 locations were considered as baseline period. Under future predicted climates, model outputs indicates that all three fruit fly species will produce higher number of generations (1–2 additional generations) with 15–24% reduced generation time over the baseline period. The increased voltinism of fruit fly species due to increased temperature may lead to ≃5% higher infestation of mango fruits in India by the year 2050. Analysis of variance revealed that ‘geographical locations’ explained 77% of the total variation in voltinism followed by ‘time periods’ (11%). Such increase in the voltinism of fruit flies and the consequent increases in the infestation of mango fruits are likely to have significant negative impacts on mango protection and production.

The mango leafhopper, Amritodus atkinsoni is a serious and an endemic insect pest of mango in India. We analyzed mtCOI gene sequences from six Indian populations of A. atkinsoni for genetic...

The peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae) is a poylphagous and serious insect pest of horticultural crops. The purpose of study was to understand the spatial and temporal variations in population abundance and distribution of B. zonata in response to climate change-based variations in temperature across the India. To examine the likely possibilities of changes in abundance and distribution of B. zonata, temperature driven process based phenology models were linked with climatic data of multiple General Circulation Model (eight models) and climate change scenarios (RCP 2.6, 4.5, 6.0 and 8.5) using the Insect Life Cycle Modeling (ILCYM) software. The risk indices (establishment, generation, and activity index) were mapped and quantified the changes in respect to locations, scenarios, models and times (2050 & 2070). The risk indices results revealed that, 1.73 (0.8–1.0 establishment risk), 14.15 (>16 high abundance) and 59.69% (>8.0 generation per year) area is projected to be highly suitable for B. zonata regarding establishment, abundance and generation indices, respectively in India under current climatic conditions. In spite of decreased permanent establishment (Establishment Risk Index > 0.6) in future climatic conditions, it is predicted that abundance and generation indices would increase in all the locations of the country. The variation in the results due to use of multiple GCM-scenario combinations suggested that choice of GCM and scenario combinations have impact on future prediction of the species. Overall, results indicate that B. zonata would be significant threat to horticultural crops in India. Therefore, present findings are of immensly useful to provide important information to design integrated pest management strategies and phytosanitary measurements for local, regional and national level to restrain the insect pest activity across different layers.

The different developmental stage-associated microbiota of the peach fruit fly, Bactrocera zonata (Diptera: Tephritidae), was characterized using 16S rRNA gene (V3–V4 region) metabarcoding on the Illumina HiSeq platform. Taxonomically, at 97% similarity, there were total 16 bacterial phyla, comprising of 24 classes, 55 orders, 90 families and 134 genera. Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes were the most abundant phyla with Gammaproteobacteria, Alphaproteobacteria, Actinobacteria, Bacteroidia and Bacilli being the most abundant classes. The bacterial genus Enterobacter was dominant in the larval and adult stages and Pseudomonas in the pupal stage. A total of 2645 operational taxonomic units (OTUs) were identified, out of which 151 OTUs (core microbiota) were common among all the developmental stages of B. zonata. The genus Enterobacter, Klebsiella and Pantoea were dominant among the core microbiota. PICURSt analysis predicted that microbiota associated with B. zonata may be involved in membrane transport, carbohydrate metabolism, amino acid metabolism, replication and repair processes as well as in cellular processes and signalling. The microbiota that was shared by all the developmental stages of B. zonata in the present study could be targeted and the foundation for research on microbiota-based management of fruit flies. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13205-020-02381-4) contains supplementary material, which is available to authorized users.

The next generation sequencing (NGS) approach has facilitated the investigations of gut microbiota with high throughput and resolution. The present study was focused on the taxonomic and functional characterization of bacterial community associated with different developmental stages of melon fly, Zeugodacus cucurbitae using 16S ribosomal RNA (rRNA) gene amplicons metagenomics. Z. cucurbitae is considered an invasive and most staid polyphagous pest of cucurbitaceous and other related crops. The taxonomic analysis of highly variable V3-V4 region of bacterial 16S rRNA gene sequencing indicated that the bacterial community associated with Z. cucurbitae consists of a total of 23 bacterial phyla (including unclassified and unassigned bacteria), comprising 32 classes, 69 orders, 99 families and 130 genera. Proteobacteria, Firmicutes, Actinobacteria and Tenericutes were dominant phyla of which family, Enterobacteriaceae was the most abundant in the larval and adult female stages, whereas Mycoplasmataceae was the dominant in the pupal stage. In larval stages of Z. cucurbitae, genus Providencia and Comamonas were the most abundant. However, genus Candidatus-Bacilloplasma and Klebsiella were the most dominant in pupae and adult females of Z. cucurbitae, respectively. PICRUSt analysis conducted for prediction of metabolic activities revealed that associated microbiota were involved in membrane transport, carbohydrate metabolism, amino acid metabolism, energy metabolism, replication and repair processes as well as cellular processes and signalling. The higher number of OTUs was annotated for phosphoglycerate mutase and transketolase in adult females followed by larval stages, which may support the digestive function of the microbiota in larvae and adult females. Our findings provide insights about the high variation in microbiota across developmental stages and basis for microbiota-based management strategies of fruit flies.

Tomato production is limited by many biotic stresses of which root knot nematode (RKN, Meloidogyne incognita) is a major pest. The present study aimed to identify resistance sources in controlled conditions and compare molecular markers for efficient and rapid screening of M. incognita resistance. Among the ten genotypes evaluated, HAT-310 and HAT-311 were found immune to M. incognita infestation. Further, six crosses with these two resistant sources, (HAT-311 x Swarna Lalima, HAT-296 x HAT-311, EC-596747 x HAT-311, Swarna Lalima x HAT-310, EC-596743 x HAT-310 and Swarna Lalima x HAT-311), exhibited immune responses against M. incognita. Four molecular markers viz. JB-1, REX-1, PMi12 and Mi23 were employed in eighteen germplasm to characterise resistance and susceptibility of the genotypes against infestation by M. incognita. JB-1 yielded 420 bp in all the genotypes after digestion and hence could not be used to differentiate between nematode resistance and susceptibility. Marker PMi12 yielded additional DNA fragments in addition to the expected bands and did not give consistent results. REX-1 and Mi23 markers successfully differentiated between nematode resistant and susceptible genotypes. Moreover, Mi23 separated the homozygous and heterozygous resistance sources since the restriction enzyme analysis was not needed. The resistant genotypes identified from the present study may be used further in nematode resistance breeding programmes of tomato and the Mi23 marker can be used for rapid screening of the germplasm.

Trichoderma asperellum (NAIMCC-F-03167) and Hypocrea nigricans (NAIMCC-F-03168) were isolated from the acidic soil of the vicinity of Litchi orchard, Ranchi, Jharkhand and were characterized on the basis of morphological, molecular and biochemical features. Both strains are fast growing, light to dark green, highly sporulative and have ability to cover 90 mm Petri dish within 96 h of inoculation. Biochemcial estimation of both isolates indicated significant cellulase and phosphate solubilisation activity. Highest cellulase activity was observed in T. asperellum (5.63 cm) followed by H. nigricans (5.10 cm) and phosphate solubilisation index was observed maximum in T. asperellum (1.93) followed by H. nigricans (1.39). Moreover, these isolates were molecularly identified on the basis of ribosomal DNA based sequences database and phylogenetic analysis in NCBI GenBank as T. asperellum (NCBI-KM 438015) and H. nigricans (NCBI-KJ910335). Negetive effect on sporulation of Lead (Pb) and Cadmium (Cd) was observed while in heavy metal scavenging potential, T. asperellum (88.9% Cd) showed highest scavenging potential followed by H. nigricans (87.2% Cd) while in Pb scavenging potential, H. nigricans (88% Pb) followed highest scavenging potential followed by T. asperellum (81.30% Pb) after 21 days of inoculation from 30 µg/ml heavy metals concentrated broth medium. If both potential bioagents can apply in Cd and Pb affected soil/water will be helpful in scavenging of heavy metals as well as management of phosphorus deficiency and soilborne fungal diseases.

The oriental fruit fly, Bactrocera dorsalis (Hendel) is a major pest of mango crop in India and the present studies conducted to estimate the number of generations in relation to changing temperature on mango fruits across eight different geographically isolated major mango growing locations of India. The prediction of insect pest generations and generation time was done for baseline (1961 to 1990),present (1969 to 2005), near future (2021 to 2050) and distant future (2071 to 2098) periods using A1B emission scenario data from the regional circulation model (RCM), Providing Regional Climates for Impacts Studies (PRECIS) model. The degree days models using minimum and maximum temperature were used to obtain cumulative degree days (DD) for each generation of B. dorsalis using a temperature threshold of 13°C. It was estimated that faster accumulation of degree days would make possible for occurrence of one or two additional generations with shortened mean life cycle (5 to 7 days less) in near and distant future climate change periods compared to baseline and present periods at majority of locations. Increased number of generations and reduction of generation time at majority of mango growing locations of India suggest that the incidence of B. dorsalis may likely to increase due to projectedincrease in temperatures during future climate change scenarios.

The peach fruit fly, Bactrocera zonata, is among the most serious and polyphagous insect pest of fruit crops in many parts of the world under genus Bactrocera. In the present study, the genetic structure, diversity and demographic history of B. zonata in India were inferred from mitochondrial cytochrome oxidase 1 (cox1) and NADH dehydrogenase 1 (nad1) sequences. The efficiency of DNA barcodes for identification of B. zonata was also tested. Genetic diversity indices [number of haplotypes (H), haplotype diversity (Hd), nucleotide diversity (π) and average number of nucleotide differences (k)] of B. zonata populations across India maintain high level of genetic diversity without isolation by distance among the geographic regions. Non-significant negative correlation between pairwise Fst and geographic distance suggests a high level of gene flow among studied populations of B. zonata. The possibility of sudden expansion of B. zonata revealed through mismatch distribution analysis as well as negative Tajima's D and Fu's Fs values further supported by star-like network of haplotypes. DNA barcoding analysis suggests that B. zonata specimens can be clearly differentiated from other species with 100% accuracy of identification. Therefore, cytochrome oxidase 1 (cox1) barcode sequences generated in the present study could be a valuable source for the rapid identification and global population genetic study of B. zonata.

The study examined the genetic diversity and demographic history of Bactrocera dorsalis, a destructive and polyphagous insect pest of fruit crops in diverse geographic regions of India. 19 widely dispersed populations of the fly from India and other Asian countries were analysed using partial sequences of mitochondrial cytochrome oxidase I (cox1) and NADH dehydrogenase 1 (nad1) genes to investigate genetic diversity, genetic structure, and demographic history in the region. Genetic diversity indices [number of haplotypes (H), haloptype diversity (Hd), nucleotide diversity (π) and average number of nucleotide difference (k)] of populations revealed that B. dorsalis maintains fairly high level of genetic diversity without isolation by distance among the geographic regions. Demographic analysis showed significant (negative) Tajimas’ D and Fu’s F S with non significant sum of squared deviations (SSD) values, which indicate the possibility of recent sudden expansion of species and is further supported through distinctively star-like distribution structure of haplotypes among populations. Thus, the results indicate that both ongoing and historical factors have played important role in determining the genetic structure and diversity of the species in India. Consequently, sterile insect technique (SIT) could be a possible management strategy of species in the regions.

Pink bollworm (PBW), Pectinophora gossypiella is one of the most destructive pest's globally inflicting huge economic losses in cotton even during later stages of crop growth. In the present investigation, the population genetic structure, distribution, and genetic diversity of P. gossypiella in cotton growing zones of India using partial mitochondrial DNA cytochrome oxidase-I (COI) gene was addressed. The overall haplotype (Hd), number of nucleotide differences (K), and nucleotide diversity (π) were 0.3028, 0.327, and 0.00047, respectively which suggest that entire population exhibited low level of genetic diversity. Zone-wise clustering of population revealed that central zone recorded low level of Hd (0.2730) as compared to north (0.3619) and south (0.3028) zones. The most common haplotype (H1) reported in all 19 locations could be proposed as ancestral/original haplotype. This haplotype with one mutational step formed star-like phylogeny connected with 11 other haplotypes. The phylogenetic relationship studies revealed that most haplotypes of populations are closely related to each other. Haplotype 5 was exclusively present in Dharwad (South zone) shared with populations of Hanumangarh and Bathinda (North zone). The result indicated that there is no isolation by distance effect among the Indian populations of PBW. The present study reports a low genetic diversity among PBW populations of India and H1, as ancestral haplotype from which other haplotypes have evolved suggests that the migration and dispersal over long distance and invasiveness are major factors.

The aim of the present study was to identify the cultivable gut bacteria associated with peach fruit fly, Bactrocera zonata, and evaluate their potential to attract adults of B. zonata. Based on culture-dependent characterization methods and 16S rRNA gene sequence analysis, bacteria were identified as members of family Enterobacteriaceae (BZM1, Klebsiella oxytoca), Microbacteriacea (BZM2, Microbacterium spp.) and Nocardiaceae (BZM4, Rhodococcus spp.). Molecular phylogeny placed Klebsiella oxytoca within gram negative γ-proteobacteria whereas, Microbacterium spp. and Rhodococcus spp. were clustered under gram positive Actinobacteria group in family Microbacteriacea and Nocardiaceae, respectively. 16S rRNA gene sequence comparison with the available NCBI database sequences further confirmed the characterizations of bacterial symbionts. Population of these bacterial species increased significantly up to the 11th day after emergence of adults and thereafter it remains constant. Among 3 bacterial symbionts, metabolites produced from K. oxytoca had the highest attraction to the B. zonata adult females over metabolites produced from other bacteria and their combinations in field bioassay. The B. zonata adult male flies attracted to metabolites produced from each bacterial symbionts alone and their combinations were less in number with comparison to the B. zonata adult females. The present study provides the first description of the attractancy potential of metabolites produced by gut microbial community of B. zonata in open field condition. This study results may prompt the development of a female-targeted population control strategy for this fly.

Mitochondrial genome can provide information for genomic structure as well as for phylogenetic analysis and evolutionary biology. The complete 15,935 bp mitochondrial genome of Bactrocera zonata (Diptera: Tephritidae), is assembled from Illumina MiSeq read data. The mitogenome information for B. zonata was compared to the homologous sequences of other tephritids. Annotation indicated that the structure and orientation of 13 protein coding genes (PCGs), 22 tRNA and 2 rRNA sequences were typical of, and similar to, the ten closely related tephritid species. The nucleotide composition shows heavily biased toward As and Ts accounting 73.34% and exhibits a slightly positive AT skew, which is similar to other known tephritid species. All PCGs are initiated by ATN codons, except for cox1 with TCG and atp8 with GTG. Nine PCGs use a common stop codon of TAA or TAG, whereas the remaining four use an incomplete termination codon T or TA likely to be completed by adenylation. All tRNAs have the typical clover-leaf structure, with an exception for trnS((AGN)). Four short intergenic spacers showed high degree of conservation among B. zonata and other ten tephritids. A poly(T) stretch at the 5' end followed by [TA(A)]n-like stretch and a tandem repeats of 39 bp has been observed in CR. The analysis of gene evolutionary rate revealed that the cox1 and atp6 exhibits lowest and highest gene substitution rates, respectively than other genes. The phylogenetic relationships based on Maximum Likelihood method using all protein-coding genes and two ribosomal RNA genes confirmed that B. zonata is closely related to Bactrocera correcta, Bactrocera carambolae, Bactrocera papayae, and Bactrocera philippinensis and Bactrocera dorsalis belonging to B. dorsalis species complex forms a monophyletic clade, which is in accordance with the traditional morphological classification and recent molecular works.

The peach fruit fly, Bactrocera zonata, is among the most serious and polyphagous insect pest of fruit crops in many parts of the world under genus Bactrocera. In the present study, the genetic structure, diversity and demographic history of B. zonata in India were inferred from mitochondrial cytochrome oxidase 1 (cox1) and NADH dehydrogenase 1 (nad1) sequences. The efficiency of DNA barcodes for identification of B. zonata was also tested. Genetic diversity indices [number of haplotypes (H), haplotype diversity (Hd), nucleotide diversity (π) and average number of nucleotide differences (k)] of B. zonata populations across India maintain high level of genetic diversity without isolation by distance among the geographic regions. Non-significant negative correlation between pairwise Fst and geographic distance suggests a high level of gene flow among studied populations of B. zonata. The possibility of sudden expansion of B. zonata revealed through mismatch distribution analysis as well as negative Tajima’s D and Fu’s Fs values further supported by star-like network of haplotypes. DNA barcoding analysis suggests that B. zonata specimens can be clearly differentiated from other species with 100% accuracy of identification. Therefore, cytochrome oxidase 1 (cox1) barcode sequences generated in the present study could be a valuable source for the rapid identification and global population genetic study of B. zonata.

The complete mitogenome of Idioscopus nitidulus (Cicadellidae) was sequenced. It comprises 15,287 base pairs (bp), including 13 protein-coding genes (PCGs), 2 rRNA genes, 22 tRNA genes and a control region. The phylogenetic analyses based on concatenated thirteen protein-coding genes of mitogenomes recover the monophyly of Auchenorrhyncha (Fulgoromorpha + Cicadomorpha) and Sternorrhyncha as a sister group to Auchenorrhyncha. The complete mitogenome sequence of Idioscopus nitidulusis available in the GenBank with accession number: KR024406.

Zeugodacus caudatus (Fabricius) is a pest of cucurbit plants. The present study was conducted to draw the relationship among Indian Z. caudatus populations with the other defined genetic lineage of the species. A total of 18 individuals’ mtCOI gene sequences from 3 populations of India were analysed along with 34 individuals’ mtCOI gene sequences from Malaysia, Indonesia, Thailand and China and generated 14 haplotypes. Phylogenetic study revealed the presence of distinct genetic lineage in Z. caudatus populations collected from India. The genetic distance between three distinct lineages of Z. caudatus was 0.057, 0.055 and 0.018 between Indonesia and Malaysia, India and Indonesia, and India and Malaysia, respectively and also evident from phylogenetic analysis. Further, the mitochondrial cytochrome oxidase I (COI) gene sequences developed in this study will help detection and geographical distribution of new haplotypes and lineages of the species in future.

The mango fruit borer, Citripestis eutraphera (Meyrick), originally confined to the Andaman Islands, is a recent invasion in mainland India. With changes in climatic conditions, the pest is likely to spread in other major mango-growing regions of the country and can pose serious threats to mango production. In this backdrop, the present study examines the impact of climate change to develop spatio-temporal distribution of invasive C. eutraphera in India using the maximum entropy (MaxEnt) modelling approach. Integration of point data on current occurrence of pest and corresponding bioclimatic variables in MaxEnt were used to define the potential distribution in India and mapped using spatial analysis tool in ArcGIS. The model framework performed well as indicated by high area under the curve (0.97) value. Jackknife test for estimating predictive power of the variables indicated that ‘isothermality’ and ‘temperature seasonality’ significantly affected C. eutraphera distribution. It was found that mango-growing pockets in the southwestern parts of Gujarat, as well as parts of Kerala and Tamil Nadu were moderately to highly suitable for C. eutraphera distribution in 2050 and 2070. The results of this study could be an important guide for selecting monitoring and surveillance sites and designing integrated pest management policies in the context of climate change against this invasive pest of mango.

Torrubeilla pruinosa, a teliomorph of an anamorphic entomopathogenic fungus Hirsutella versicolor on mango hopper (Idioscopus clypealis) was observed. On the infected mango hopper, tiny pin head signs of ascomata were observed. Ascomata of T. pruinosa is pale brown or tawny brown, crowded, immersed in stroma, wall dark golden brown, 260–320 × 230–260 μm, asci clavate, hyaline and thin walled. The ascospores of T. pruinosa are fusiform, distoseptate with a faint tint of pigmentation, 17.5–25.0 × 5.0–7.5 μm. The anamorph stage of H. versicolor fungal hyphae is hyaline, septate and profusely branched, and conidiogenous (phialides) cells are hyaline, pear-shaped and smooth-walled with single or double sterigmata and rarely, multiple sterigmata. Each sterigmata bears single conidia which are hyaline, oval to pear-shaped.

The litchi stink bug Tessaratoma javanica (Thunberg) (Hemiptera: Tessaratomidae) is a minor insect pest of litchi (Litchi chinensis Sonn.) in India. Recently, an outbreak of litchi stink bug was observed in the Chotanagpur plateau of Jharkhand, India, during February–April 2011. A description of the outbreak is given in this report. Females were found to be highly fecund and caused severe damage to the litchi crop (>80%) in the region. Incubation period of eggs was found to be 12.80 days. The mean nymph population was 45.66 nymphs per 30-cm shoot length, and the maximum was159 nymphs, observed during March and April 2012 on litchi trees. The outbreak of the pest may be due to the migration of bugs from wild kusum (Schleichera oleosa (Lour.) Oken) plants (a host plant of the litchi stink bug) to the cultivated litchi crop. During the course of the investigation, two natural enemies were found on litchi stink bug, viz., Anastatus bangalorensis Mani & Kurian and Ooencyrtus sp. However, the natural parasitization by the parasitoids was very low, 3.5%. Considering the damage caused to the litchi crop in this region, the recent outbreak created an alarming situation for the pest management researchers of the country to develop suitable integrated pest management strategies in the near future. Otherwise this will become a major problem to the litchi growers as well as to industries associated with this delicious fruit in India.

An anamorphic entomopathogenic fungus Neozygites sp. belonging to the Family Neozygitaceae was found infecting the tetranychid mites Tetranychus urticae Koch (Acari: Tetranychidae) of French bean (Phaseolus vulgaris L.) for the first time in Eastern Plateau and Hill region of India in the month of October 2011. The report of entomopathogenic fungus could be of help in managing acaricide resistant mites.

An entomopathogenic fungus belonging to the genus Hirsutella was found infecting the mango hopper, Idioscopus clypealis (Lethierry) (Hemiptera: Cicadellidae), for the first time in India in September 2011. The report of a natural control agent of mango hopper during the off season has special significance because its outbreak depends upon its residual hibernating population.

Intensification of agricultural yield losses due to pest aggravation in the context of global climate change has been the key focus of ecological research. In this regard, interest in forecasting models is now days growing radically among entomologists to predict the environmental suitability for new and invading agricultural insect pests. This chapter describes the approaches for development of temperature-based phenology models that helps in understanding insect behaviour and physiology under diverse environmental conditions. A few suitable illustrations are provided on how phenology models can be used for simulating variability in insect development times through stochastic and deterministic simulation functions with inclusion of temperature as a main predictor of insect development. Further, discussions were also included on linking of phenology models with geographic information systems (GIS) for mapping pest population growth potentials according to real-time or interpolated temperature data, as a tool for pest risk assessments in different agro-ecological regions and to support the development of management strategies. The concepts and approaches underlying simulation of age-stage-structured populations using cohort-updating and rate summation principle and the use of geostatistical algorithms integrated in GIS for risk mapping are described briefly.

Tessaratoma javanica (Thunberg) (Hemiptera: Tessaratomidae) an important sucking pest of litchi is studied for supplementing information on its biology, morphometrics of life stages and mtCOI (DNA barcodes). More details generated on the study add to the description of stages namely egg, 1st to 5th nymphal instars and adults. The evaluation of morphometrics of the life stages reveal that the progression of growth is more during 2nd to 3rd nymphal stages, and these are critical as far as the growth and development is concerned. The life cycle takes about 141.7±4.25 days; eggs last for 12.81±1.4 days with 97.14±2.86% hatchability; and duration of 1st , 2nd, 3rd, 4th and 5th nymphal instars were 11.69±0.58, 7.23±0.2, 8.63±0.55, 13.04±0.55 and 26.31±0.97 days, respectively. In addition mtCOI analyses have been done employing standard 658 bp barcode fragments facilitating molecular diagnostics of the adults and other life stages and the phylogenetic tree with available sequence in the GenBank.