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Termites, being a major subterranean insect pest of sugarcane, are generally managed through insecticidal applications, although multiple non-chemical options are available. In the present study, attempt was made to evaluate different entomopathogens, insecticides and a cultural method against termites under field condition. Four entomopathogens (Beauveria bassiana, Metarhizium anisopliae, Purpureocillium lilacinum and Bacillus subtilis), four insecticides (Chlorantraniliprole, Imidacloprid, Bifenthrin and Chlorpyrifos) and one treatment of cultural practice of weekly irrigation for 4 weeks from planting onwards along with untreated control were evaluated as treatments for the management of termites. Although insecticides were found most effective tools in managing termites in sugarcane, the entomopathogens were also found to be quite successful and surprisingly weekly irrigation failed to check the termite infestation. A significant diversity and abundance of different taxon of micro-arthropods were recorded in different treatments. Environmental impact quotient (EIQ) and EIQ-Field use rating (EIQ-FUR) of different chemical pesticides revealed a significant impact on diversity and abundance of micro-arthropods in sugarcane agro-ecosystem. In order to minimise the use of chemical insecticides, the present study indicates a possibility of integrated approach in managing termites in sugarcane agro-ecosystem.

Termites, being serious pests of sugarcane, have been posing threat to its cultivation in Indo-Gangetic plains of North-West zone of India. Monthly observations round the year revealed a highest per cent incidence of termites in the month of August to the tune of 25.45% followed by 22.73, 21.82, 18.18 and 15.45% in the months of July, September, October and June, respectively. The incidence was lower in winter months, i.e. January, February and March with 4.55, 5.45 and 7.27%, respectively. It is evident from the weather data that monsoon season with high relative humidity and moderate temperature was favourable for the build-up of the population of termites, while winter season was unfavourable. Study on relative abundance of different species of termites in sugarcane revealed that termite species, Odontotermes obesus, occupied the maximum percentage of occurrence to the tune of 28.57% followed by that was 21.42, 14.28, 14.28, 14.28 and 7.14% of Microtermes obesi, O. horni, O. vaishno, O. bellahunisensis and Odontotermes sp., respectively. Of the total species recorded during the course of study, three species, viz. Odontotermes horni (Wasmann), O. vaishno Bose and O. bellahunisensis Holmgren and Holmgren, were recorded for the first time to infest sugarcane in India. An illustrated key was developed for easy and quick identification of termite species collected from sugarcane. The study holds promise for strategic planning for the management of termites in sugarcane agro-ecosystem.

Utilization of plant defence mechanism against insect pests is considered to be a viable and environmentally safe strategy. In the present study, attempt was made to decipher the morphological and biochemical factors contributing towards resistance/susceptibility of sugarcane genotypes against top borer, Scirpophaga excerptalis Walker, a major insect pest in subtropical region of India. The experiment was conducted at the experimental farm of ICAR-Indian Institute of Sugarcane Research, Lucknow, India. Nine sugarcane varieties, viz. CoS 94257, CoSe 92423, CoPant 97222, CoS 96268, CoS 767, Co 0238, CoLk 94184, CoJ 64 and CoLk 8102 were selected from a diverse group in terms of growth period, degree of pest infestation and other morphological characters. Observations taken on various morphological characters of different sugarcane varieties showed a significant difference on pest incidence. Out of these morphological parameters studied, the thickness of leaf midrib (r = − 0.56) and plant height (r = − 0.44) recorded significant and negative linear correlation with incidence of top borer. However, leaf breadth showed significant and positive correlation (r = 0.52) with incidence of top borer. Amongst the biochemical parameters, such as reducing sugar, total phenol, poly phenol oxidase-specific activity, proteinase inhibitory activity, total soluble protein, nitrogen, phosphorus, potassium contents, correlation study revealed that the reducing sugar was significantly positively correlated (r = 0.77) while proteinase inhibitor activity (r = − 0.82) showed significantly negative correlation. It is noteworthy that the total phenol and polyphenol oxidase activity were significantly positively correlated to proteinase inhibitory activity. The study holds promise for future varietal development programme.

A conceptual model of habitat augmentation for subtropical sugarcane ecosystem has been established to enhance its self-regulatory capacity for pest protection by linking species interrelationships and their trophic interactions. In order to ensure adequate number of predators and parasitoids to deliver the desired level of pest control, strategic approach is needed to support natural enemies. The provisioning of food for their adults, alternate hosts in the vicinity, shelter, etc., through habitat alteration may be the sustainable answer. The innovative design in this model that is integration of lac cultivation in the neighborhood of sugarcane is expected to prolong food availability to adult parasitoids, alternate host and shelter. The lac insect and its host plant are excellent source of honey dew, nectar and is available almost year round. The associated insect fauna of lac is not only potential natural biocontrol agents but also lac cultivation supports honey bee population. It is believed that such a model of habitat augmentation in conjunction with the presently available tools in biological insect management will be more effective with a lower cost of operation. The additional cash income through lac is another benefit to sugarcane farmers. We anticipate that the ecological and economic benefits of the suggested model may add value to the sugarcane ecosystem and will attract attention of all the stakeholders associated with this commercial crop.

White grubs are polyphagous subterranean insect pests which have recently emerged as a major threat to sugarcane cultivation. For effective management of these pests in sugarcane, studies were undertaken to evaluate various locally isolated as well as commercially available microbial biocontrol agents, entomopathogenic nematodes and novel chemical pesticides against white grubs. Attempts were made to isolate effective bio-agents associated with white grubs in indo-gangetic plains of India. Altogether, nine local bacterial isolates associated with infected white grubs were isolated and tested for their bio-efficacy under laboratory condition. However, none of the isolates were found effective against the predominant species, Holotrichia consanguinea. Hence, attempt was made to assess the field efficacy of already available five microbial bio-agents, viz., Metarhizium anisopliae, Beauveria bassiana, Bacillus cereus strain WGPSB-2, Heterorhabditis indica, Steinernema carpocapsae and three insecticides, viz., Chlorantraniliprole 0.4 G, Fipronil + Imidacloprid 80 G and Chlorpyriphos 10 G at their recommended doses. Results of the experiments conducted for 2 years under randomized block design revealed that treatment of Bacillus cereus strain WGPSB-2 @10 kg/ha (1 × 1013 cfu/ha) could reduce the white grub damage to the extent of 59.8%, while other bio-agents could reduce the damage in the range of 24.3–39.5% over untreated control. All the insecticides were found effective in reducing white grub damage, and in most of the observations, difference in reduction in the white grub damage was statistically non-significant. However, Chlorantraniliprole 0.4 G @ 20 kg/ha was most effective, which could reduce the grub damage to the extent of 89.10% over untreated control.

The impact of planned honeybee pollination on the seed production of three Brassica vegetables, Brassica oleacea var. italica, B. rapa pekinensis and B. oleracea var. gongylodes and the pollination behaviour of Apis mellifera was studied under Indian Himalayan conditions. Among the three crops tested, more number of bees were found visiting broccoli crop under net house condition (6.05 bees/plant) followed by kohlrabi (5.35 bees/plants) and Chinese cabbage (5.05 bees/plant). Bees spent more time in Chinese cabbage flower (6.92 sec) while it was 6.50 sec in broccoli and 5.54 sec in kohlrabi. Bees in the open conditions were found to spend less time in a flower as compared to the net house conditions. Honeybees played an important role in enhancing the seed production of all the crops under study. Planned honeybee pollination was found to inflict maximum impact on the seed production of broccoli with an increase in seed yield of 29.2 per cent. The net profit was also more in case of broccoli, which was calculated to be 1324.60$ per ha in honeybee pollinated broccoli crop when compared to the natural pollinated crop.

We describe the isolation, biochemical characterization, phylogenetic analysis, and pathogenecity of a novel entomopathogenic bacterium Brevibacterium frigoritolerans to first instar larvae of Anomala dimidiata and Holotrichia longipennis. The almost full length 16S rRNA sequence of the bacterium has 99% identity with the type strain of B. frigoritolerans, while phylogenetic analysis revealed that the isolate formed a tightly linked branch with the type strain of B. frigoritolerans. Under in vitro bioassay conditions, the isolate infected and caused 89±5.4 and 74±7.7% mortality, in first instar larvae of A. dimidiata and H. longipennis, respectively. The infected larvae exhibited bacteremia like symptoms and mortality occurred between the second and fifth weeks after inoculation. This is an early report on the entomopathogenic potential of the hitherto lesser-known bacterium Brevibacterium frigoritolerans.

An endophytic Serratia marcescens strain SRM (MTCC 8708) isolated from the flowers of summer squash was found to be entomopathogenic against the larvae of Helicoverpa armigera. Natural epizootic of this bacterial strain on the larvae collected from summer squash flowers ranged from 19.9 to 72.3%. Under laboratory conditions, a dose of 6 × 1010 c.f.u./ml diet induced 66.3% mortality of first instar H. armigera larvae. Similarly all other growth and development parameters of the insect were severely retarded in a dose-dependent manner. The bacterium invaded the entire alimentary canal and haemolymph with successful replacement of all other gut-associated microflora. There was a great reduction in midgut proteinase activity due to inhibition of five major proteinase isozymes by S. marcescens infection. Further, a synergistic interaction between chitinases isolated from this strain and Bacillus thuringiensis Cry1Ac toxin was observed. The present findings suggest that this plant-associated S. marcescens strain SRM could be suitably exploited for the management of H. armigera.

BACKGROUND: Diamondback moth, Plutella xylostella (L.), is a major insect pest of crucifers in the biodiversity-rich north-western Indian Himalayan hills. The present investigation was aimed at determining the susceptibility pattern of P. xylostella populations collected from different locations of this region to autochthonous and standard Bacillus thuringiensis strains. RESULTS: Among the reference as well as indigenous B. thuringiensis strains tested, sub spp. kurstaki HD-1, kurstaki HD-73, galleriae HD-8, local galleriae/colmeri strain BtOa1 and some of their Cry1 class toxins were found to be highly toxic. Surprisingly, the sub sp. tolworthi HD-125, local tolworthi strain BtHa1 and Cry9 class toxins were found to be non-toxic. Midgut homogenate from fourth-instar larvae was found to activate 130 kDa protoxin from the local tolworthi strain BtHa1 into 68 kDa toxin, but failed to exert any larval mortality, probably owing to lack of receptor binding. CONCLUSION: The present study provides valuable baseline susceptibility data for the deployment of B. thuringiensis-based control methods, as well as for future monitoring of development of resistance in P. xylostella to B. thuringiensis in this ecologically sensitive region. Copyright © 2008 Society of Chemical Industry

The north-western Indian Himalayan hill region contains around 40 phytophagous species of white grub (Coleoptera: Scarabaeidae). Anomala dimidiata and Holotrichia seticollis are the predominant species. Under natural conditions, up to one-fifth of the population of the grubs was found to exhibit symptoms of bacterial infection. Therefore, we attempted to isolate and characterize the most potent bacterium for the management of white grubs. Of 27 bacterial isolates tested against A. dimidiata, WGPSB-2 was found to be highly toxic. Based on morphology, physiology, biochemistry and sequencing of the 16S rRNA gene, the isolate WGPSB-2 was identified as Bacillus cereus. A dose determination bioassay indicated that first instar grubs of A. dimidiata and H. seticollis were more susceptible than second instars. Although the LT90 values for second instar grubs exceeded 8 weeks, the grubs stopped feeding after ingestion of spores, mostly after the third week. In outdoor microplots, a dose of 1.7 × 1010 spores/m2 app...

White grubs (Coleoptera: Scarabaeidae) are cosmopolitan and polyphagous insect pests of agricultural crops, forests and pastures around the world. The lack of an environmentally sound approach for white grub management has prompted the exploration and detection of a novel microbial biocontrol agent against these sub-terranean insect pests. In this study we describe the isolation, establishment of pathogenesis, biochemical characterization and phylogenetic analysis of an entomopathogenic Bacillus cereus strain WGPSB-2 (MTCC 7182), isolated from an atrophied pupa of Anomala dimidiata, collected from the N.W. Indian Himalayas. The sequencing and subsequent comparison of the 16S rDNA revealed that the strain has100% similarity with Bacillus cereus sequences. Phylogenetic analysis of the 16S rDNA sequence revealed that the isolate is closely related to Bacillus thuringiensis and Bacillus sphaericus. In vitro bioassays showed that the isolate was able to infect and cause 92 and 67% mortality in second ...

Campoletis chlorideae Uchida (Hymenoptera: Ichneumonidae) is an important solitary larval endoparasitoid of the tomato fruit borer Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) in India. The interaction between Bacillus thuringiensis subspecies kurstaki (Btk) HD-1 and C. chlorideae was studied under laboratory condition to explore their compatibility in managing H. armigera. The results had indicated that the growth and development of H. armigera was affected in a dose-dependent manner upon feeding on sublethal doses of Btk HD-1-treated diets. There were no larval survivors in lethal doses of Btk HD-1 (LC70 and LC90). The growth and survival of the parasitoid were normal when the host larvae were fed with sublethal doses or subjected to short time exposure to lethal doses of Btk HD-1. However, the parasitoid offsprings developed slowly and pupal as well as adult period, adult weight and adult emergence rate were reduced significantly if the parasitoid was developing inside a severely Bt intoxicated host larvae. There were no evident differences in longevity of parasitoid adults that were fed on honey solution containing different concentrations of Btk HD-1 as compared to adults fed only on honey solution. This indicates no direct adverse effect of Btk HD-1 on C. chlorideae. Further, the gravid female parasitoid did not discriminate Btk HD-1 intoxicated and normal H. armigera larvae for oviposition. The result implies that spore crystal formulation of Btk HD-1 can be effectively used in a synergistic manner along with existing natural or prereleased population of C. chlorideae in organic farming or as components in biointensive IPM module for managing H. armigera.

A series of experiments were carried out to determine the acute toxicity of pesticides in the laboratory, toxicity through spray on flowering plants of mustard (Tier II evaluation) and field on both Apis cerana and A. mellifera bees. The overall mortality of honey bees through topical (direct contact) were found significantly higher than that of indirect filter paper contamination assays. Insecticides viz., chlorpyriphos, dichlorvos, malathion, profenofos, monocrotophos and deltamethrin when exposed directly or indirectly at their field recommended doses caused very high mortality up to 100% to both the bees at 48 HAT. The insecticides that caused less mortality through filter paper contamination viz., flubendiamide, methyl demeton, imidacloprid and thiamethoxam caused very high morality through direct exposure. Apart from all the fungicides tested, carbendazim, mancozeb, chlorothalonil and propiconazole, insecticides acetamiprid and endosulfan were found safer to both the bees either by direct or indirect exposures. Tier II evaluation by spray of pesticides at their field recommended doses on potted mustard plants showed monocrotophos as the highly toxic insecticide with 100% mortality even with 1h of exposure followed by thiamethoxam, dichlorvos, profenofos and chlorpyriphos which are not to be recommended for use in pollinator attractive flowering plants. Acetamiprid and endosulfan did not cause any repellent effect on honey bees in the field trials endorse the usage of acetamiprid against sucking pest in flowering plants.

A new trivoltine lac insect species, Kerria sharda, sp. nov. (Homnoptera: Tachardiidae) infesting Schleichera oleosa (Lour.) Oken is reported from eastern ghat region of Orissa, India. It differs from the closest species K. albizzae (Green), by having marginal ducts numbering 24–30 in each of 6 clusters, subequal branchial and supra-anal plates and 3–4 segmented antennae, as against 10–15 marginal ducts, branchial plate longer than supra anal plate and 2 segmented antennae of albizzae.

Scale insects are notorious pests but humans have successfully exploited some of them to their advantage. The Indian lac insect, Kerria lacca (Homoptera) is one such insect which is purposely cultured in some Asian countries such as India, Thailand, China and Vietnam for its various products of commercial importance (resin, wax and dye).

White grubs, a group of destructive insect pests of polyphagous nature, cause severe damage to crop plants in hill ecosystem. The grubs with subterranean habitat feed extensively on the roots and the adults defoliate the plants. A two pronged strategies involving an efficient, light weight, eco-friendly, low cost, light based insect trap for capturing the adults and a novel entomo-pathogen, Bacillus cereus strain WGPSB-2 for the management of grubs were developed. Large scale deployment of the above technologies were done on community basis in 5 locations including 4 villages and one experimental farm of Krishi Vigyan Kendra, Uttarkashi district of Uttarakhand. Three years experimentations revealed drastic reduction in beetle population to the tune of 75.8% in low, altitude villages. A significant reduction of the grub population was recorded from 74.11% to 85.17% in three years across the different villages. As a result of reduction in grub population, per cent increase in yield of different crops was recorded from 39.0% to 59.2% in different villages and experimental farm of low hills. The technology is thus, capable of managing white grubs at different altitudes of hills in general and North Western Himalayas in particular.

The American serpentine leaf miner, Liriomyza trifolii (Burgess) was observed as an important pest of tomato crop. Studies were conducted on the efficacy of selected insecticides against this pest. Larval mining cause greater injury. Among eight insecticides tested for their efficacy against L. trifolii on variety Avinash of tomato, Profenophos 40% + Cypermethrin 4% was found to be the most effective over control, while other insecticides were also showed significant result on the leaf miner infestation.