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Trichogramma chilonis Ishii is an endoparasitic wasp widely used as a biological control agent of economically important pests. However, absence of genetic information on T. chilonis hampers further research, especially at the molecular level. Here, we performed the first RNA-Seq of the adult T. chilonis. A total of 18,372,639 high-quality reads were generated using Illumina pair-ended sequencing platform. De novo assembly resulted into 24,488 transcripts, with mean length and N50 values of 1444.2 bp and 2667 bp, respectively. Of the transcripts, 14,643 exhibited putative homology with class Insecta proteins from UniPROT database. To understand the contig functions, gene descriptions, gene ontology and cluster of orthologous group annotations were analyzed. Following functional annotation, a number of transcripts encoding detoxification, target receptor action and olfaction- related proteins were identified and analyzed. In addition, 4520 transcripts containing simple sequence repeats, ranging from dinucleotide to hexanucleotide repeats were discovered, with trinucleotide being the most enriched repeats. This new sequence resource will shed light on various molecular mechanisms in T. chilonis and related species.

Fall armyworm, Spodoptera frugiperda (J.E. Smith), is a polyphagous pest invaded India and seriously threatened maize and other crops. The detailed information on its occurrence and damage severity in the invaded regions are limited. In this study, we assessed the occurrence, incidence and damage severity of fall armyworm in 126 maize fields in 10 districts of Karnataka during the rainfed condition. Further, potential co-occurrence of this pest with native stem borers and its natural enemies explored to tackle this pest. Survey reports revealed that the fall armyworm was well distributed across the maize growing regions of Karnataka with 44–100% field infestation. The damage incidence of S. frugiperda was 22.13–46.83% with damage severity 0 to 4.9 on the 0 to 9 scale. The larval count was 0.93 ± 0.17 to 3.07 ± 0.58 per 10 plants across the locations. The co-occurrence of S. frugiperda with the native maize stem borers, Chilo partellus (Swinhoe) and Sesamia inferens (Walker) was less than 5% of the plants. It shows that S. frugiperda had dominated the native stem borers causing significant damage to maize. This study found five parasitoids parasitizing the egg, egg-larval, larval and larval-pupal stages of S. frugiperda. Trichogramma chilonis Ishii and Telenomus remus Nixon egg parasitism rates were 15.81–23.87% and 5.44–8.78%, respectively. The larval parasitoids caused 9.18% parasitism of S. frugiperda larvae. Trichogramma chilonis appeared as a major natural enemy. These data provide an important baseline for the development of sustainable management strategies for S. frugiperda.

Trichogrammatids (Hymenoptera: Trichogrammatidae) are the most important egg parasitoids widely used in different biocontrol programs worldwide. Since there are several species, strains, and ecotypes available, correct identification is the first step for successful biological control programs. Morphological identification remains complex due to subtle difference in male genetalia, therefore alternative molecular techniques were employed for rapid and reliable identification of this group of parasitoids. Furthermore, many of the field collected specimens are females, which are not identifiable using morphological keys. This study was carried out to unravel the discrimination success in the two molecular marker loci cytochrome oxidase I (COI) and internal transcribed spacer-2 (ITS-2) region of trichogrammatids. In achieving these objectives, the single specimen of 22 trichogrammatids belonging to 19 species were subjected to DNA extraction, PCR amplification, and sequencing. Additionally, we obtained homologous sequences from GenBank and sequences in BOLD database to understand internal relationships between the trichogrammatids. Bayesian inference phylogenetic analysis conducted with 84 and 76 sequences of COI and ITS-2 loci respectively and studied discrimination among the different species. Based on trees in comparison, we observed that there was a total of 10 and 6 out of 19 species correctly discriminate with COI and ITS-2 respectively. Our result revealed that the ITS-2 gene was less divergent than the COI gene in the majority of species and failed to differentiate all terminal clades. Therefore, we recommend that COI is suitable as the primary DNA barcode locus in trichogrammatids. Overall, we suggest that COI gene has higher discrimination power and can be considered as an appropriate molecular marker for species identification in trichogrammatids.

ITS-2-RFLP method was employed to distinguish 12 different trichogrammatids consisting of indigenous and exotic species such as Trichogrammatoidea armigera and Tr. bactrae , Trichogramma achaeae , T. chilonis , T. japonicum , T. embryophagum , T. pretiosum (Thelytokous Form—TF), T. brassicae , T. dendrolimi , T. evanescens and T. mwanzai . ITS-2 region was amplified; complete ITS-2 sequences of nine species were deposited in Genbank. The size of the amplified product ranged from 500 to 900 bp. Restriction enzyme digestion of ITS-2 region showed different banding profiles for these 12 species. Dichotomous keys using the size of the ITS-2 product and the restriction fragment length polymorphism for the enzymes (EcoRI, MseI, MvaI, and TaqI) allowed quick species identification of these trichogrammatids.

The eggs of the factitious host insect, Corcyra cephalonica (Stainton), are used for production of several natural enemies in many countries across the world. Trichogramma spp. are used widely for the biological control of lepidopterous pests on various crops in more than 30 countries covering a total area of 3.2 million ha of agricultural and forest land. A novel and simple technique for storage of eggs of C. cephalonica by vacuum packing at 500 Hg−1 and stored at 8 ± 1 °C in refrigerator was developed to enhance egg viability for production of Trichogramma species, and assessed and compared with the traditional method. The percent parasitism of vacuum packed eggs was 100.0–75.0% after storing for 7–42 days and declined to 10.0% after 70 days storage compared to 100.0, 50.0, 40.0 and 5.0% parasitism after 7, 14, 21 and 28 days, respectively, in the traditional method. The percent emergence from parasitized eggs was identical in both vacuum and non-vacuum packed eggs indicating suitability of vacuum packing eggs. The percent females ranged 50.0–59.0% in vacuum-packed eggs and 48.4–55.8% in non-vacuum packed eggs. Vacuum packing enhanced storability of C. cephalonica eggs by 3- to 4-fold as compared to the traditional method of storage.

The baseline-susceptibility of Indian populations of Helicoverpa armigera (Hubner) to the insecticidal protein Cry1Ac, from Bacillus thuringiensis (Berliner) was determined through bioassays conducted in 1999 and 2001. Populations of H. armigera were collected from cotton fields of nine major cotton growing states in India, which included (field locations in parentheses) Punjab (Bathinda), Haryana (Sirsa), Rajasthan (Sriganganagar), Madhya Pradesh (Barwah and Khandwa), Gujarat (Rajkot, Vadodra and Anand), Maharashtra (Jalgoan, Jalna, Akola and Yavatmal), Andhra Pradesh (Adilabad, Warangal, Khammam and Guntur), Karnataka (Raichur, Davangere and Ranebennur) and Tamil Nadu (Coimbatore and Dindigul). All populations were susceptible to Cry1Ac. The mean lethal concentrations, LC50—ranged from 0.14 to 0.71 and from 0.11 to 0.61; LC90 ranged from 1.17 to 6.94 and from 1.02 to 6.70 μg of Cry1Ac / ml of diet in 1999 and 2001 populations, respectively. Similarly, moult inhibitory concentrations, MIC50—ranged from 0.05 to 0.27 and from 0.05 to 0.14; MIC90—values ranged from 0.33 to 1.58 and from 0.25 to 0.91 μg of Cry1Ac in 1999 and 2001 populations, respectively. The effective concentrations (weight stunting related) EC50 ranged from 0.003 to 0.008 and from 0.0003 to 0.004; EC90 ranged from 0.029 to 0.076 and from 0.009 to 0.054 μg of Cry1Ac in 1999 and 2001 populations, respectively. These values form the baseline data for susceptibility of H. armigera to Cry1Ac and can be used as benchmarks for monitoring resistance to Cry1Ac. Bt cotton, expressing Cry1Ac, was approved for commercial cultivation in India in 2002.