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Aims: The current study was conducted to know the compatibility of natural enemies and botanical for management bhendi fruit borers in the bhendi field. Study Design: Randomized Complete Block Design (RCBD). Place and Duration of Study: Experiment conducted during 2019-20 and 2020-21 at ICAR- National Bureau of Agricultural Insect Resources, Hebbal, Bengaluru, Karnataka, India. Methodology: Two field tests were conducted at the entomological research farm, ICAR-NBAIR Bengaluru, Karnataka, India, to know the compatibility of the natural enemies (Trichogramma chilonis Ishii (Hymenoptera:Trichogrammatidae) , Chelonus blackburni (Cameron) and Bracon brevicornis (Wesmael) (Hymenoptera: Braconidae) and botanical (Neem oil 0.5%) for management of E. vittella and H. armigera on bhendi. Arka Nikita (IIHR) bhendi variety was used for the two trials with different treatments in four replication. The release rates of parasitoids were decided based on the previous parasitic potential studies. Results: In the first trial, among the treatments, a combination of T. chilonis + C. blackburni + B. brevicornis and C. blackburni + B. brevicornis recorded the lowest pooled mean larval population reduction over pre-treatment count of E. vittella and were on par with each other, recording 40.19% and 37.27%, respectively followed by T. chilonis + B. brevicornis (31.28%), C. blackburni (30.90%), B. brevicornis (28.64%), Neem oil 0.5% (27.71%), Neem oil 0.5% + B. brevicornis (25.46%) and T. chilonis (25.32%). A similar trend was also observed in combination of T. chilonis + C. blackburni + B. brevicornis and C. blackburni + B. brevicornis against H. armigera, which accounted for 47.19% and 37.22% of reduction over pre-treatment count in the respective treatment combination of parasitoids. The next best treatments were T. chilonis + B. brevicornis (28.21%), C. blackburni (26.56%), B. brevicornis (22.21%), Neem oil 0.5% (20.37%), T. chilonis (17.31%) and Neem oil 0.5% + B. brevicornis (16.07%) Conclusion: From this study we recommend that, for bhendi fruit borers management, release of parasitoids like T. chilonis + C. blackburni + B. brevicornis at 50,000+1000+1000 adults/ha, respectively in bhendi field starting from 35 DAS at 15 days’ intervals of duration, two-time release of parasitoids is enough later, they have augmented and reduce the population of fruit borer larvae effectively.

Aims: The current study was carried out to investigate the parasitic potential of density of two important parasitoids against the age of two important bhendi fruit borer pests. Study Design: Completely Random Design (CRD). Place and Duration of Study: The study was conducted during 2019-20 and 2020-21 at bio control laboratory of National Bureau of Agricultural Insect Resources (ICAR) Hebbal, Bengaluru (Latitude: 13.097221 Longitude: 77.568291) by adopting standard methodology and materials. Methodology: An experiment was designed to examine the effects of parasitoid densities of Bracon brevicornis and Chelonus blackburni on the host age (different instars) larvae of fruit borers two important fruit borers by checking the the percent parasitization. The second, third, and fourth instar larvae of E. vittella were introduced separately at different ratios of Bracon brevicornis parasitoids and host viz., 1:10, 2:10, 3:10, 4:10, and 5:10. Mated female parasitoids were utilised in all cases, and the experiment was carried out in a glass jar of 18 x 12 cm, using the sandwich approach. [1] with four replications. After 24 h, the larvae were observedand the percent parasitization was calculated. The same parasitoids were used for thesecond, third, fourth, and fifth instars larvae of H. armigera. To examine the parasitic potential of C. blackburni, another experiment was conducted with various ratios of its adults and eggs of E. vittella and H. armigera by adopting the procedure of Swamiappan and Balasubramanian [2]. The parasitoid and host eggs were maintained at a ratio of 1:100, 2:100, 3:100, 4:100, and 5:100 with four replications. The observation of percent parasitization was recorded after the egg incubation period. Results: The parasitic potential studies showed that the parasitoid host ratio of 5:10 (100%) was the best for E. vittella (II, III and IV instar larvae) with the highest parasitization followed by 4:10 (96.83 %), 3:10 (85.08 %), 2:10 (61.71 %) and least parasitization was observed in 1:10 parasitoid host ratio (52.71 %). Similarly, for H. armigera (II, III, IV and V instar larvae) parasitoid host ratio of 5:10 was recorded the highest parasitization (96.75 %), followed by 4:10 (93.69 %), 3:10 (84.11 %), 2:10 (64.75 %) and least parasitization was observed in 1:10 parasitoid host ratio (45.07 %) The parasitic potential of C. blackburni revealed that the 5:100 parasitoid host ratio resulted in the maximum parasitization of 64.75% against E. vittella, followed by 4:100 (60.50%), 3:100 (52.55%), 2:100 (38.27%), and 1:100 (25.60%). Similarly, for H. armigera, parasitization was highest at a parasitoid host ratio of 5:100, followed by 4:100 (64.50%), 3:100 (58.25%), 2:100 (43.45%), and 1:100 (28.50%). Conclusion: The parasitoids: host ratio of 5:10 for B. brevicornis and 5:100 for C. blackburni is optimal for managing the bhendi fruit borer complex at the IV instar level.

Six insecticides were evaluated for their toxicity against nymphs and adults of assassin bug, Sycanus collaris (Fab.) through contact and stomach mode. The studies revealed that emamectin benzoate (0.4g/L), chlorantraniliprole (0.25ml/L), flubendiamide (0.25 ml/L) and thiamethoxam (0.25 g/L) were considered as relatively safer insecticides for all the nymphal instars and adults of S. collaris. Fenazaquin (1.25ml/L) and quinalphos (2ml/L) caused higher mortality (85-100%) in all the stages of S. collaris. The higher mortality observed in nymphs and relatively lesser mortality rate of adults indicate that the application of the chemical should not be carried out immediately after the release of nymphal instars of S. collaris and adult releases would be ideal in Integrated Pest Management (IPM).

Rugose spiralling whitefly (RSW), Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae), an invasive pest to the Oriental region was found infesting several plantation crops like coconut, banana, guava, Indian almond, sapota, oil palm, mango, cashew, custard apple and several ornamental plants in southern states of India as well as Assam, West Bengal, Maharashtra, Meghalaya, Odisha, Chhattisgarh and Gujarat. Intensive surveys across different agroclimatic zones of Karnataka revealed that infestation of the pest was severe in coastal and southern region of Karnataka compared to northern region. Molecular characterization of partial mitochondrial cytochrome c oxidase–I gene (658 bp) and morphological characters of the pest and its natural enemies confirms its identity. During the study, 35 host plants were recorded, and several natural enemies viz., parasitoids, Encarsia guadeloupae, Encarsia dispersa (Hymenoptera: Aphelinidae), predators, Pseudomallada astur (Neuroptera: Chrysopidae), Jauravia pallidula, Cheilomenes sexmaculata (Coleoptera: Coccinellidae) and Cybocephalus indicus (Coleoptera: Cybocephalidae) were also observed feeding on RSW. The parasitoid E. guadeloupae was the major parasitoid associated with the pest. Natural parasitism by the parasitoids was ranging from 7–80% in the study area.

The cassava mealybug, Phenacoccus manihoti Matile-Ferrero is one of the most serious pests of cassava worldwide, which got recently introduced into India (traced in Kerala) as a potential invasive pest. Studies were carried out to record the incidence of mealybug, P. manihoti and its natural enemies on different varieties of cassava in Namakkal dt. of Tamil Nadu during June 2020. The observations were taken in the field in situ as well in the collected mealybug infested twigs in the laboratory. Results revealed that all the three surveyed cassava varieties viz. , Mulluvadi, Thailand white and Shree Atulya were found severely infested with cassava mealybug. A huge number of coccinellid beetles were collected from the P. manihoti colonies, which were identified as Hyperaspis maindroni Sicard, 1929 (Coccinellidae:Coccinellinae:Hyperaspidini). Molecular characterization of both grub and adult beetle of H. maindroni was carried out to confirm its identity.

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.

Studies on the biology and feeding potential of Eocanthecona furcellata (Wolff) on Spodoptera frugiperda (Smith) were carried out at NBAIR, Bengaluru. Experimental results revealed that the total developmental period from egg to adult for male and female were 27.92±2.87 and 39.62±3.28 d, respectively. The life cycle of male and female passed through first, second, third, fourth and fifth nymphal instars (male: 2.42±0.51 d, 3.25±0.45 d, 3.25±0.45 d, 4.00±0.60 d, 4.42±0.51 d) and (female: 2.54±0.52 d, 3.46±0.52 d, 4.00±0.71 d, 4.38±0.65 d, 5.08±0.49 d), respectively. Total nymphal period is about 17.83±1.34 d for male and 19.46±1.20 days for female, respectively. Adult longevity of male is lower (10.25±2.96 d) compared to that of female (20.15±3.39 d). The premating period and mating period of adult E. furcellata was 2.33±0.50 days and 6.44±2.24 hrs, respectively. The pre-oviposition period, oviposition period of adult female was 2.89±0.60 and 11.22±1.72 days, respectively. The average number of eggs laid by the female was 209.29±28.11 in a single mated system. Egg incubation period was about 5.42±0.51 days. The predation rates of second, third, fourth, fifth instar nymphs, adult female and male on 2 nd , 4 th , 6 th instar prey of E. furcellata were (16 ±0.95, 27 ±4.06, 55±4.67, 68 ±5.41, 126 ± 4.76, 97 ± 2.85), (7±1.34, 24±2.77, 40±3.39 45±0.71, 88±1.37, 51±1.60) and (4±0.82, 9±1.64, 21±2.81, 38±1.03, 69±1.32, 36±2.73), respectively.

The present experiment was aimed at safety evaluation of different insecticides to Cryptolaemus montrouzieri Mulsant, a major predator of mealybugs. In order to understand the impact of chemical insecticides on this predator, different bioassays were carried out. The results of the study showed that the Percent mortality of C. montrouzieri at 24 HAT was highest in profenophos 50% EC (49.33%) followed by thiamethoxam (36.00%) and dinotefuran (30.67%). However, azadirachtin, buprofezin and pymetrozine were found comparatively safer insecticide to C. montrouzieri . Therefore, both of these insecticides, need to be evaluated further under different agro-climatic zones to confirm their suitability, for mealybug management in cotton ecosystem without adversely affecting the performance of C. montrouzieri .

High percentage of Homalotylus turkmenicus Myartseva (Hymenoptera: Encyrtidae) parasitizing Hyperaspis maindroni Sicard (Coleoptera: Coccinellidae) predating on the colonies of the Cassava Mealybug (CMB) Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae) is observed in southern India. In the present study, cautionary note on the presence of H. turkmenicus in the food web of insects associated with the CMB and brief diagnosis of the parasitoid is presented for quick identification. The parasitism of Hy. maindroni grubs by H. turkmenicus ranged from 65.67 to 80.95 per cent. However, no primary parasitoid of the cassava mealybug was observed so far.

The search for new Bacillus thuringiensis ( Bt ) strains is a continuous process and researchers are now focusing on finding toxin proteins that are toxic to pests of insect orders that are not reported. In the present study soil and insect cadaver samples were collected from North East India comprising the states of Assam, Tripura and Mehhalaya and native Bt were isolated using standard protocols. At total of 30 Bt isolates were purified and characterized. Various types of crystal morphology were encountered that included bipyramidal, cuboidal, square, rhomboid, spherical and irregular. PCR analysis showed that diverse cry genes were expressed. The cry genes identified were Lepidoptera, Coleoptera and Diptera specific. Detected genes included cry1Ac , cry2A , cry4A , cry10A , cry16A , cry17A , cry19A , cry30Aa , cry44Aa , cry11A , cry4B , cry12A , cry8A and cry7A . Many of them were positive for Vip3A protein. The coleopteran specific Bt were evaluated against Sitophilus oryzae and Callosobruchus chinensis and NBAIR-AgBt6 was found to be toxic. The isolates are being further evaluated for use as biopesticides.

During the surveys undertaken in July-September 2020, a braconid solitary koinobiont endoparasitoid, Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae: Euphorinae) was found parasitizing the invasive pest, fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in maize. Meteorus pulchricornis is a new addition to the known and rapidly expanding parasitoid complex of FAW in India. The present study provides morphological identification details of M. pulchricornis along with comparison notes of other closely allied and confusing species.

Occurrence of Spodoptera frugiperda (J. E. Smith) (Insecta: Lepidoptera: Noctuidae), commonly known as fall armyworm, in southern India is reported along with associated natural enemies. Severe damage was noticed in Chikkaballapur, Hassan, Shivamogga, Davanagere and Chitradurga during July-August 2018. The incidence ranged from 9.0 to 62.5 percent at various locations, maximum incidence was recorded in Hassan district followed by Chikkaballapur, Davanagere, Shivamogga and Chitradurga. Morphology and molecular based taxonomic tools were used for the identification of this pest. The GenBank accession number MH704433 of Chikkaballapur population was released on 1 st August, 2018 and Barcode obtained from BOLD System-ID: AGIMP054-18. The survey also revealed natural parasitism by egg parasitoids viz., Telenomus sp. (Hymenoptera: Platygastridae) and Trichogramma sp. (Hymenoptera: Trichogrammatidae), gregarious larval parasitoid, Glyptapanteles creatonoti (Viereck) (Hymenoptera: Braconidae) solitary larval parasitoid, Campoletis chlorideae Uchida (Hymenoptera: Ichneumonidae), and a solitary indeterminate larval-pupal (Hymenoptera: Ichneumonidae: Ichneumoninae) parasitoid. Spodoptera frugiperda is the first host record for G. creatonoti across the globe. Glyptapanteles creatonoti , being a well established parasitoid of various noctuids in India and Malaysia, was capable of parasitizing S. frugiperda . Besides these, other commonly found bioagents viz., Forficula sp. (Dermaptera: Forficulidae) and entomopathogenic fungus Nomuraea rileyi (Farl.) Samson was also collected in large numbers. We report the natural enemy complex of S. frugiperda for the first time from India. The electro physiological response of Indian population of S. frugiperda male adults to pheromone was established. The studies to manage this pest by any/all means are in progress.

New challenges appear with every biological invasion and presses need to probe their ecological interactions. In the comprehensive yet complicated food web associated with the niche of the recently invaded cassava mealybug (CMB) Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae), there was a multitrophic interaction structured vertically as well as horizontally. Altogether 45 species: thirty four species of insects from six orders (Coleoptera, Diptera, Hemiptera, Hymenoptera, Lepidoptera, and Neuroptera) and eleven species of spiders (Araneae) were grouped under four trophic levels into 11 guilds. The analysis of trophic guild structure and interaction indicated that many indigenous parasitoid species, which qualified to be placed under the fourth trophic level, actively parasitized the potential native predators of cassava mealybug (CMB) and thereby negatively impacted the natural biological control of CMB. Most of these resident hyperparasitoid species were recorded for the first time, to be associated directly or indirectly with CMB. The species diversity at fourth trophic level could be viewed as a bioindicator and one of the most important determinant factors on the success rate of any biological control program. No indigenous primary parasitoids were documented on CMB from any of the sites sampled. In the absence of any indigenous parasitoids and high level of parasitization of the potential CMB predators, the long-term and indirect ecosystem risks will be significant until the introduction and establishment of the proven classical biological control agent, Anagyrus lopezi (De Santis) (Encyrtidae: Hymenoptera) from other countries.

Eocanthecona furcellata (Wolff) is a potential native predator of lepidopteran larvae that can be easily reared under laboratory conditions and released in augmentative biocontrol for management of pests in various crops. For successful mass production of any predator cannibalism under crowded rearing conditions is the major limiting factor. In the present study, attempts were made to know the ideal population considered for group rearing with minimal or no cannibalism. It was recorded that the predator population of 5 to 25 on Corcyra cephalonica (S.) and Galleria mellonella L. and 5 to 30 on Samia cynthia ricini Boisd. and Spodoptera litura F. was feasible for group rearing with higher percent survival rate when reared in different group arenas. The survival percent was higher on hosts, C. cephalonica, G. mellonella, S. litura and recorded lower on S. cynthia ricini under group rearing condition.Â

Two species of predacious bugs, Eocanthecona furcellata (Wolff) and Andrallus spinidens (Fabr.) (Hemiptera:Pentatomidae) were found effectively preying on Spodoptera frugiperda (Smith) in organically grown maize from 28 to 56 days at GKVK, Bangalore. Population of E. furcellata in one square metre was more than A. spinidens during the 38 th and 39 th standard meteorological weeks. Adults and nymphs of both the species preyed on different stages of S. frugiperda larvae. These two species being initial colonizers has a potential in integrated management of fall army worm.

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.

Inostemma indicum Mani, a parasitoid of Neolasioptera cephalandrae Mani (Diptera: Cecidomyiidae), collected from stem galls of ivy gourd (Coccinia grandis (L.) Voigt (Cucurbitaceae)) was described by Mani in 1941. The original description is scanty and ambiguous, with little diagnostic value. The holotype, a dissected female mounted on a slide, is lost. It is redescribed with illustrations and a neotype is designated. The previously unknown male is also described.

The Grey Weevil, Myllocerus subfasciatus Guerin, is an important emerging pest of quarantine significance in Solanaceae crops including the eggplant, Solanum melongena. Entomopathogenic nematodes (EPNs) have been shown to be a potential source of safe and effective control of M. subfasciatus. In this study, we determined the virulence of seven strains of EPNs (Nematoda: Rhabditida) viz. Heterorhabditis bacteriophora NBAIIHb105, H. indica NBAIIHi101, H. indica NBAIIHiMah, Steinernema abbasi NBAIISa01, Steinernema abbasi NBAIISa04, S. carpocapsae NBAIISc04 and S. glaseri NBAIISg01, with different foraging behaviour, against larvae of eggplant grey weevil, M. subfasciatus (Coleoptera: Curculionidae), and their suitability in five representative soils from the eggplant grown areas under laboratory conditions. All seven nematode strains caused80% mortality of M. subfasciatus larvae at 40 IJs/cm2. LC90 values ranged between 21.18 and 46.41 IJs/cm2 at 96 h post-application, which corresponded to field concentrations between 2.1-4.6×109 IJs/ha. H. indica NBAIIHi101, S. glaseri NBAIISg01, S. abbasi NBAIISa01 and S. carpocapsae NBAIISc04 recorded higher grub mortality, compared to H. indica NBAIIHiMah, H. bacteriophora NBAIIHb05 and S. abbasi NBAIISa04 indicating existence of inter- and intra-specific variation in virulence. Response Surface Modelling (RSM) optimized LC and LT values for maximised larval mortality. RSM predicted a concentration of 58.05-62.54 IJs/cm2 of these EPN (corresponding to a field dose of 5.8-6.2×109 IJs/ha) required for effecting 97.10-99.67% grub mortality, at 90-97 h of exposure. EPN strains performed better in terms of larval mortality in loamy sand, alluvial, mountain soil, red laterite compared to black cotton soils. Efficacy of EPN was positively correlated with the content of sand, and negatively with the clay content. It is possibly the first report that established the potential of local strains of EPNs with different foraging ability and their dosages for suppression of subterranean root feeding larvae of M. subfasciatus in five broad soil types of eggplant grown areas. Validation of this baseline data in real-time eggplant crop situations may help in evolving EPN-based viable management schedules for M. subfasciatus.

The present study was carried out to assess the field efficacy of endophytic isolates of Beauveria bassiana (Bb-5a, Bb-23 and Bb-45) and Metarhizium anisopliae (Ma-35) against maize stem borer (Chilo partellus Swinoe) during kharif seasons of 2015 and 2016 at ICAR-National Bureau of Agricultural Insect Resources (NBAIR), Attur Farm, Bengaluru, Karnataka. All the tested isolates showed suppression of maize stem borer damage during both seasons. Pooled data indicated that lesser dead hearts (9.5-12.71%), stem tunnelling (3.98-4.36 cm/plant) and exit holes (2.59-2.79 /plant) in the treated plants compared to untreated control which showed 21.38% dead hearts, 8.01 cm/plant of stem tunnelling and 6.99 exit holes/plant. Among the four isolates tested, Bb-5a isolate of B. bassiana and Ma-35 isolate of M. anisopliae showed significantly superior effect in lowering the incidence of dead hearts (9.50 and 12.71%), stem tunnelling (3.98 and 4.36 cm/plant) and exit holes (2.59 and 2.79/plant) with higher yields of 72 and 70.0 tonnes/ha respectively.

Comparative biology of invasive rugose spiralling whitefly (RSW) Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae) was studied on three host plants viz., coconut (Cocos nucifera L), banana (Musa spp. L) and Indian shot (Canna indica) under caged as well as field conditions. The RSW life cycle was shorter on coconut as compared to that of banana and Indian shot plant. Thus, coconut is the preferred host for its growth and development with a fecundity of 49.50± 4.09 eggs and total duration of the nymphal instars being of 23.2± 1.38 days. Duration to lifestages on banana was less under field conditions as compared to that under caged conditions. These results on the comparative biology and growth will help to develop suitable IPM strategies for this invasive pest.

Laboratory and field evaluation of some insecticides (buprofezin 25 SC, pymetrozine 50 WG, flonicamid 50 WG, dinotefuran 20 SG, thiamethoxam 25 WG, profenophos 50 EC), botanical (azadirachtin 10000 ppm) and entomopathogenic fungus (Isaria fumosorosea Wize) were carried out against the invasive rugose spiralling whitefly Aleurodicus rugioperculatus Martin on banana. The results revealed that azadirachtin 10000 ppm (86.49%), dinotefuran 20 SG (82.64%), pymetrozine 50 WG (72.72%) and thiamethoxam 25 WG (79.59%) caused significant mortality of first and second instar nymphs at 2 days after treatment (DAT). Profenophos 50 EC (77.61%) and azadirachtin 10000 ppm (71.53%) were significantly effective and on par with mortality at 2 DAT of third and fourth instar nymphs. Flonicamid 50 WG was the most toxic with the least LC50 value (507.8 and 646.1) and buprofezin 25 SC was the least toxic with maximum value (1245.1 and 1752.0) for early and late instar nymphs, respectively. Profenophos 50 EC and LC50 buprofezin 25 SC also showed maximum ovicidal effect. Under field conditions, I. fumosorosea with 100% mortality was significantly superior compared to dinotefuran 20 SG (97.23%), thiamethoxam 25 WG (95.02%) and azadirachtin 10000 ppm (94.98%) at 6 DAT.

Mealybugs are found attacked by various natural enemies in nature. The outbreak of mealybugs was observed in many instances with the application of broad-spectrum insecticides, which might have disturbed the activity of natural enemies particularly parasitoids and predators. This clearly indicates the importance of natural enemies in the regulatory role of the mealybug population. In fact, there is a very rich natural complex on arboreal mealybugs, but there is a poor natural enemy complex, particularly natural predators or parasites on root mealybugs. Withdrawal of insecticides results in the reappearance of natural enemies, thereby regulating the mealybug population. The natural enemies of the pests can be divided into three categories depending on how they feed on the pests. They are predators, parasitoids or pathogens.

During last decade many invasive mealybugs were reported as major threat to agriculture in India. Among these, the recently introduced mealybug, Phenacoccus madeirensis Green (Hemiptera: Pseudococcidae) was observed expanding its horizons to cotton growing areas of South Karnataka and Maharashtra. Since it is necessary to study its lifecycle, so as to identify the vulnerable stage, the present study was undertaken during 2014–15 under laboratory conditions on cotton. The results revealed that its males had a slightly longer nymphal period (22.4± 1.49 days) compared to females (20.96± 1.03 days) due to additional pupal stage. Fecundity of female ranged from 215–398 eggs/female. The pre-ovipositional, ovipositional and post-ovipositional periods lasted for 9.6± 0.93, 5.56± 0.69 and 4.12± 0.81days, respectively. Adult female lived for 25.04± 1.50 days, while its adult males lived for only 2.48± 0.49 days. The total developmental period of females lasted for 48.28± 2.12 days and in males 24.88± 1.98 days.