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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.

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...

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 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.

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.