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Housefly, Musca domestica is used as an alternate host to rear a eulophid, Nesolynx thymus (Girault), a pupal parasitoid of the tachinid fly, Exorista bombyci s (Louis) which in turn is an endolarval parasitoid of Bombyx mo ri (L.). An attempt was made to evaluate the host factors like pupal size, age and exposure periods of N. thymus for developing robust mass multiplication methods. The host size had significant effect on mean parasitism by N. thymus . Mated females of N. thymus when exposed to host pupae of varying size, revealed that mean per cent parasitisation was significantly higher (74%) in large sized pupae having a volume of 263.89 mm3. Regarding host age, 24 - 48 h old host pupae had higher level of parasitism (65%) by N. thymus . The parasitism rate declined with an increase in host age after 72 h. In field evaluation, release of N. thymus at weekly interval resulted in the reduction of housefly population as evinced from the higher parasitism (56 %) of the sentinel cards placed in the treated poultry sheds. The information on host factors generated will help to enhance the mass multiplication of parasitoid for the release of which would aid to bring down the M. domestica population in poultry and dairy units.

The present study was conducted to collect and identify the species of trichogrammatids from eggs of lepidopteran pests infesting the diverse cropping systems in the country. A total of 28 plant species were inspected for the collection of lepidopteran eggs either through collection of insect eggs or by placing sentinel egg cards. The species such as Trichogramma chilonis Ishii, T. achaeae Nagaraja and Nagarkatti, T. danausicida Nagaraja, Trichogrammatoidea bactrae Nagaraja and Tr. armigera Manjunath were recorded naturally occurring with 12 species of lepidopteran insect pests. In nature, the parasitism rate varied from 5.35 to 82.25% by the associated trichogrammatids. A total of 596 sentinel trap cards were placed in the agricultural, vegetables, fruits crops, and grasses on the bunds of fields to trap the egg parasitoids present in the different habitat. Through sentinel cards, three species, viz. , T. chilonis , T. achaeae and Tr. bactrae were found inhabit the vegetables and ornamental crops. The percentage of adult emergence from the sentinel trap cards ranged from 70.59 to 100.0%. Natural parasitism of Tr. bactrae recorded for the first time on the eggs of Lampides boeticus L. infesting wild species of Crotalaria . In addition, the natural parasitism of Tr. armigera and Tr. bactrae on the eggs of L. boeticus laid on either cultivated or wild relatives of Crotalaria in undisturbed habitat had higher natural parasitism due to their bright yellow flower attracts parasitoids to parasitize the eggs and conserve these egg parasitoids. Recently, natural parasitism of Trichogramma sp. was recorded on invasive fall armyworm, Spodoptera frugiperda (J.E. Smith) infesting maize in Karnataka. Based on the present work, there could be choice of selecting right species which occur naturally on individual crops.

Host-insect and host-plant associated differentiation of genetically divergent microbiota were recorded from economically important egg parasitoid collected from 26 locations in India, Trichogramma chilonis constituted 86.8% of the populations collected. It was recorded from 14 host-insects, 14 different crops and weed plants from 12 states. Nine species of yeast were recorded from parasitoid from 5 host-insects with Wickerhamomyces anamalus was isolated from 36.4% samples and highest numbers were recorded from parasitoid collected on sugarcane. Bacillus cereus, Pseudomonas sp. and Stenotrophomonas maltophilia from T. chilonis constitute 64.3% of bacterial diversity based on their 16S rDNA sequences. For taxonomic identification using 16s rDNA and ITS sequences, we performed taxonomic classification of total 33 ITS isolates against UNITE Fungal ITS database and assigned taxonomy hierarchy to the sequences. Also, a total of 13 isolates 16s rDNA sequences were taxonomically assigned against RDP 16s rDNA database using RDP Naive Bayesian rRNA Classifier Version 2.1. Most of the species are correctly identified in the respective species members with high confidence threshold value support.