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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.

Spodoptera frugiperda (J E Smith) (fall armyworm) (Lepidoptera: Noctuidae), is a key pest of maize that has recently entered in India causing damage and yield loss. A biocontrol-based integrated pest management (IPM) strategy was designed and evaluated in farmer’s field during rabi and kharif season (2018–2019). IPM strategy comprising installation of controlled release FAW pheromone traps, four releases of Trichogramma pretiosum Riley, two sprays of neem oil, one spray of each Bacillus thuringiensis (NBAIR-BT25) and Metarizium anisopliae (NBAIR Ma-35) resulted in 76 and 71.64% egg mass; 80 and 74.44% larval population reduction at 60 days after treatment during rabi and kharif season, respectively. Cob yield per acre in biocontrol-based IPM field was higher than the farmer’s practice (6–7 sprays of emamectin benzoate 5% SG) during both the seasons, and it resulted in 38.3 and 42.29% gain in yield per acre during rabi and kharif, respectively. Therefore, this module forms a base to manage the fall armyworm in an eco-friendly and farmer friendly manner. Future research with other alternatives has also been discussed.

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.

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.

Inheritance of monocrotophos resistance was studied in the laboratory population of T. chilonis. After 10 cycles of selection pressure under laboratory condition, the resistant strain acquired LC50 value of 0.346mL compared toLC50 value of 0.114 mL in the susceptible strain. Evidence from bioassay of F1 reciprocal hybrid crosses backcrossed with respective resistant 'R' and susceptible 'S'parentalstrains of T. chilonis, aimed to determine mode of inheritance of insecticide tolerance indicated that F1 crosses exhibited a complete dominant response to monocrotophos, with degree of dominance value (D) of 1.62. The resistance factor (Rf) of resistant strain was 3.04 folds and of F1 crosses were 3.675 folds over susceptible strain. Result of this study suggests resistance to the insecticide was probably controlled by a single gene. These results provide the basic information for designing successful management programmes for the control of Lepidopteran pests using resistant strain as a component of IPM.

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.

In today's commercial world, multilevel inverters is playing a significant role from power failure. Harmonics is a major problem in power systems that have become serious recently owing to the wide use of power electronics related equipment. In this process, there is a possibility of generation of harmonic peaks because majority of the power utilities are non-linear loads. A high performance multilevel inverter should have a clean output voltage with low total harmonic distortion (THD) for both linear and non linear loads. Harmonic distortion is the most important power quality problem occurring in multilevel inverter, the harmonics can be eliminated by an optimal selection of switching angles. A hybrid evaluation technique evaluates the obtained optimal switching angles that are attained from the fuzzy inference system as well as neural network. The proposed technique is tested with a seven level cascaded H-bridge inverter. The proposed method will be implemented in MATLAB working platform and the harmonic elimination performance will be evaluated.

BACKGROUND: Genetically engineered corn (Bt corn) expressing Bacillus thuringiensis Berliner insecticidal protein Cry1Ab is a biotechnological option being considered for management of lepidopteran corn pests in India. As a resistance management practice it was essential to determine the sensitivity of multiple populations of the stalk borer Chilo partellus (Swinhoe), pink borer Sesamia inferens (Walker) and the cob borer Helicoverpa armigera (Hubner) to Cry1Ab protein through bioassays. The insect populations were collected during growing seasons of Rabi 2005 (October 2005 to February 2006) and Kharif 2006 (May to September 2006). RESULTS: Multiple populations of the three lepidopteran corn pests were found to be susceptible to Cry1Ab. Median lethal concentrations (LC50) ranged between 0.008 and 0.068 µg Cry1Ab mL−1 diet for 18 populations of C. partellus (across two seasons), between 0.12 and 1.99 µg mL−1 for seven populations of H. armigera and between 0.46 and 0.56 µg mL−1 for two populations of S. inferens. CONCLUSION: Dose–response concentrations for lethality and growth inhibition have been determined to mark baseline sensitivity of multiple populations of key lepidopteran corn pests in India to Cry1Ab protein. These benchmark values will be referenced while monitoring resistance to Cry1Ab should Bt corn hybrids expressing Cry1Ab be approved for commercial cultivation in India. Copyright © 2010 Society of Chemical Industry

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.

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.

The host egg preference studies revealed that Trichogramma chilonis, which was collected from 8 crops, preferred the eggs of Corcyra cephalonica most (84.8% parasitism), followed by Chilo partellus (55.1%) and Helicoverpa armigera (47.9% parasitism) and Samia ricini eggs were least preferred, T. achaeae was recorded from eggs collected from 3 crops only. The parasitoids obtained from rice, sugarcane, cabbage and dolichos were more robust rather than other 4 crops. The parasitoids collected from sugarcane showed strong recognition to the crop when released back on sugarcane, while parasitoids from other crops did not show any pattern of host-plant recognition. Sugarcane appeared to be the most preferred crop for T. chilonis releases with parasitism of 30.5%, followed by paddy (18.9%), cotton (18.3%) and tomato was the least preferred host plant.

Trichogrammatids are being mass reared and released in different ecosystems for control of lepidopterous pests for the past seven decades in India. Indiscriminate use of pesticides often results in decline in the natural enemy population besides development of tolerance in the pests and their resurgence and secondary pest outbreaks. With intensification of agriculture, pesticide consumption has increased drastically from 1950–1951 to 1990–1991 and later decreased from 1991–1992 to 2000–2001 mainly due to integrated approach, environmental concerns, and introduction of newer molecules. Among the major groups of pesticides in India – insecticides are consumed more, followed by herbicides and fungicides. Cotton receives more quantity of the pesticides (52–55 %) followed by paddy (17–18 %) and horticultural crops (13–14 %) as in 2001–2002. In the IPM program, chemical pesticides are integrated with biocontrol methods like release of egg parasitoids and biopesticides. Among 36 species of trichogrammatids described from India, only a few are being commercially mass reared and released. About ten such species have been tested for sensitivity to different pesticide groups. Those already tested include 4 in organochlorine group, 13 in organophosphates group, 12 in synthetic pyrethroid group, 32 in biopesticide group, and 21 in combination compounds for safety to biocontrol agents including trichogrammatids. Out of ten species screened for toxicity to various chemicals, T. chilonis has been more intensively screened against various pesticides by several researchers followed by T. japonicum and T. (= brasiliense) pretiosum. One of the main reasons for T. chilonis being the most widely screened against various pesticides and by various workers is due to its most dominant position in various ecosystems in India and its integration in IPM modules. In the future, studies should be oriented towards the safety of newly introduced pesticides, including combination compounds and biopesticides. Efforts should also be made to better understand the mechanism of populations building up tolerance, besides persistence by using different modern toxicological tools.

The South American tomato moth Tuta absoluta (Meyrick) is a devastating pest of tomato. In the present study Tuta-adapted strains of Trichogramma were evaluated. Amongst the three species, Trichogramma achaeae Nagaraja and Nagarkatti, Trichogramma pretiosum Riley and Trichogrammatoidea bactrae Nagaraja could parasitise T. absoluta eggs and the parasitism rates were 5.0%, 51.1% and 68.2% respectively. Adults emerged from the parasitized T. absoluta eggs (4.8%, 97.5% and 90.0% adult emergence respectively). The F1 generation adults of T. pretiosum could parasitise 29% of Corcyra cephalonica Stainton eggs, while the other two species were not successful in parasitizing. In addition, four 'hymenopteran' parasitoids, viz. T. achaeae , Neochrysocharis formosa (Westwood), Habrobracon sp. and Goniozus sp. were also observed to be associated with T. absoluta in the fields during the surveys undertaken in southern India.

This paper presents an investigation of seven level cascaded H-bridge (CHB) inverter in power system for compensation of harmonics.For power quality control a Fuzzy Logic Control (FLC) giving comparatively better harmonic reduction than the conventional controllers. Harmonic distortion is the most important power quality problem stirring in multilevel inverter, the harmonics can be eliminated by an optimal selection of switching angles. A hybrid evaluation technique evaluates the obtained optimal switching angles that are attained from the fuzzy inference system as well as neural network. The proposed method will be implemented in MATLAB working platform and the harmonic elimination performance will be evaluated.

The declining activity of the growth hormone--insulin-like growth factor I (IGF-I) axis with advancing age may contribute to the decrease in lean body mass and the increase in mass of adipose tissue that occur with aging.To test this hypothesis, we studied 21 healthy men from 61 to 81 years old who had plasma IGF-I concentrations of less than 350 U per liter during a six-month base-line period and a six-month treatment period that followed. During the treatment period, 12 men (group 1) received approximately 0.03 mg of biosynthetic human growth hormone per kilogram of body weight subcutaneously three times a week, and 9 men (group 2) received no treatment. Plasma IGF-I levels were measured monthly. At the end of each period we measured lean body mass, the mass of adipose tissue, skin thickness (epidermis plus dermis), and bone density at nine skeletal sites.In group 1, the mean plasma IGF-I level rose into the youthful range of 500 to 1500 U per liter during treatment, whereas in group 2 it remained below 350 U per liter. The administration of human growth hormone for six months in group 1 was accompanied by an 8.8 percent increase in lean body mass, a 14.4 percent decrease in adipose-tissue mass, and a 1.6 percent increase in average lumbar vertebral bone density (P less than 0.05 in each instance). Skin thickness increased 7.1 percent (P = 0.07). There was no significant change in the bone density of the radius or proximal femur. In group 2 there was no significant change in lean body mass, the mass of adipose tissue, skin thickness, or bone density during treatment.Diminished secretion of growth hormone is responsible in part for the decrease of lean body mass, the expansion of adipose-tissue mass, and the thinning of the skin that occur in old age.

A strain of T. chilonis, an egg parasitoid of lepidopteran pests tolerant to the most commonly used cyclodiene insecticide--endosulfan was developed in the laboratory. Tolerance to endosulfan was induced by exposing adult parasitoids sequentially from a sub-lethal concentration (0.004%) to the field recommended concentration (0.09%). The strain acquired tolerance to the insecticide after 341 generation of continuous exposure with LC50 values of 1074.96 ppm as compared to LC50 of (70.91 ppm) in susceptible strain. The genetical study showed that F1 crosses exhibited a semi-dominant response to endosulfan with degree of dominance value (D) of 0.58. The resistant factor of tolerant strain was 15.1 folds and of F1 cross were 8.53 folds over susceptible strain. Under net house conditions, the tolerant strain parasitised 56% Helicoverpa armigera eggs on potted cotton plants immediately after an insecticide spray, compared to 3% by the susceptible strain. High percentage survival of the immature stages of the tolerant strain proved their ability to withstand the insecticide load. Breakdown of insecticide tolerance in the strain occurred after four generations in absence of insecticide load. Use of the tolerant strain as a component of bio-intensive IPM in various crops where insecticide use is higher is discussed.