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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 diversity and population structure. The analysis of mtCOI sequence revealed 14 unique haplotypes and a low level of nucleotide diversity. mtCOI gene sequence analysis also revealed that A. atkinsoni specimens were clearly differentiated from other closely related species with a high level of accuracy.

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 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.

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 projected increase in temperatures during future climate change scenarios.

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.

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.