19 research outputs found
Electrophysiological and behavioral response of red palm weevil, Rhynchophorus ferrugineus (Olivier) (Coleoptera: Dryophthoridae) to fermented coconut sap neera
Red palm weevil (RPW) (Coleoptera: Curculionidae) is a lethal pest of coconut in India and various palms across the world. Fermenting toddy has been traditionally used for trapping RPW. The traditional method of collecting neera, the coconut inflorescent sap, in an open earthen pot emanates volatiles that attract these insects. In this study, the volatile compounds released from fermenting neera were characterized and the compounds that cause physiological and behavioral response to RPW were established using electrophysiological and behavioural assays. Acetoin, which caused the neuronal response in adult RPW antennae, was present in head space volatiles of fermenting neera from day one onwards. Fermenting neera, when used in tandem with aggregation pheromone, trapped a high number of weevils (53.2 per trap) suggesting possibilities of its use in RPW management
Olfactory response of red palm weevil, Rhynchophorous ferrugineus (Olivier) (Coleoptera: Dryophthoridae), to host / food volatiles
Red palm weevil, Rhynchophorus ferrugineus (Olivier), is a destructive pest of palms across the globe. Concealed nature of the pest is a hurdle in its management. Pheromone traps are a vital component in integrated management of the pest. Previous experiences reveal that use of pheromone, in isolation, trapped lower number of weevils as compared to their use in tandem with food baits. Attempts were made to study physiological and behavioral response of RPW to food baits viz., banana, pineapple and coconut petiole. Electrophysiological responses revealed that head space volatiles trapped from banana elicited the highest EAG response of 0.7 mV followed by pineapple (0.65 mV) and coconut petiole (0.2 mV). Behaviourally, orientation of adult weevils to banana, pineapple and coconut petiole volatiles ranged from 70 to 75 per cent. In field assay, banana volatiles compounds with aggregation pheromone attracted a higher mean number of adult weevils of 55.3, followed by 51.7 with pineapple and 40.6 with coconut petiole volatiles
Foraging specificity of Tetralonia (Thygatina) macroceps (Hymenoptera: Apidae: Anthophorinae) on Argyreia cuneata (Convolvulaceae)
Floral specificity is a behavior that evolved due to mutualistic interactions between the plant-pollinator community. Flowers advertise themselves using visual or chemical cues to attract pollinators and gain reproductive success through pollination. Pollinators forage for rewards such as nectar or pollen produced by the flowers. We found that an anthophorid bee, Tetralonia macroceps, foraged specifically on Argyreia cuneata flowers. No visitation was observed on the flowers of A. nervosa though both belong to Convolvulaceae. T. macroceps was the most abundant floral visitor (5.21 bees/flower/5 min) on A. cuneata and did not visit A. nervosa. Mass flowering and narrow tubular flower structure with easy access to pollen in A. cuneata were the traits that accounted for the foraging specificity of T. macroceps. The present study investigates the preference of T. macroceps for the flowers and floral extracts of A. cuneata and A. nervosa. The bee visited 10.16 flowers/5 min of A. cuneata. T. macroceps were highly attracted to the flowers of A. cuneata. No bees were attracted to A. nervosa. The floral abundance of A. cuneata was relatively higher compared to A. nervosa. Pollen analysis of foraging bees of T. macroceps revealed the selective preference towards the pollen of A. cuneata. The highest number of bees preferred the extract of A. cuneata (7.75) compared to A. nervosa (0.50) in the Y-olfactory maze. Floral extract of A. cuneata caused the highest neuronal electroantennogram (EAG) response (1.48 mV) than A. nervosa (0.36 mV). Our preliminary studies indicated the presence of specific volatile organic compounds (VOCs) nonacosane (13.26%), hexatriacontane (12.06%), and beta farnesene (6.19%) observed in A. cuneata were absent in congener A. nervosa
Controlled delivery of essential oils for the management of rhinoceros beetle (Oryctes rhinoceros L.) in coconut
Rhinoceros beetle, Oryctes rhinoceros L. (Coleoptera: Scarabaeidae), causes damage to coconut palms by feeding on the unopened fronds affecting photosynthesis. Management measures adopted include use of chemical insecticides and bioagents. Though chemical insecticides are effective, the undesirable effect on human and non-target organisms have led to dependence on botanochemicals for pest management. Essential oils derived from plant parts have the ability to cause desired control on insect pest. The limitation for use at field level is attributed to quick decline in its efficacy due to evaporation and photo degradation. Hence, this study aims to develop a polymer based delivery matrix for the release of essential oils more effectively. Essential oils (citriodora, basil and ajowan) and major constituent thymol, caused growth regulating effect in O. rhinoceros at 0.1 per cent. Among the essential oils screened, matrix loaded with basil and citriodora oils were superior with only 18 and 22 per cent incidence of spindle damage, respectively. Pest infestation in the control plots were over 74 per cent. The physical properties of the polymer matrix and dissipation pattern of actives loaded into the sheet were determined. This offers a potential to be incorporated as a component in IPM measures of rhinoceros beetle
Human-wildlife Conflict
the rise globally, and is one of the significant
environmental problems in India.
In India, HWC manifests itself in several
ways, such as wildlife poaching, retaliatory
killing of/injury to wildlife species,
crop raiding and livestock predation by
wildlife species, injury to humans or
human mortality, and destruction of
property, houses and buildings by wildlife.
Of these, wildlife conflict in agropastoral
contexts has been a subject of
debate and great concern nationally, not
only for its impact on the farmers, but
also for the consequences regarding
wildlife conflict. In India, HWC involves
multiple stakeholders and multitudinous
socio-cultural and environmental issues.
Hence any study on this topic must encompass
a multi-disciplinary effort that
provides a holistic understanding of the
history of wildlife, crop and livestock
raiding, its nature and consequences and
discuss various techniques that have been
used or recommended to mitigate the effects
of this crisis
A Sustainable Technique for Colony Multiplication by Eduction of Wild Nests of the Stingless Bee Tetragonula iridipennis Smith
Colony multiplication of stingless bees, Tetragonula iridipennis, largely relies on the eduction of wild colonies from their natural nesting sites in India. During the hiving of wild colonies, colonies were destroyed with the loss of robust wild foragers and built-in storage reserves over the years. The present study was conducted to devise a technique to sustainably multiply the colonies of stingless bees from the wild colony and the colony establishment and development during the eduction process. The annexure hives provided for eduction were accepted in a shorter time (3.25 ± 1.18 days), with the construction of storage pots observed at 7.75 ± 1.59 days after hive acceptance by the bees. The movement of foragers between the wild colony and the annexure hives was noticed for 13.80 ± 4.20 days. The foragers settled in the annexure hives and started foraging after 18.20 ± 2.49 days. The advancing fronts were observed at 26.67 ± 2.58 days after the addition of the laying queen in the established annexure hives. There was a significant increase in the number of inhive workers after the queen seeding in the annexure hives. This technique is the easiest and most sustainable non-
destructive way of multiplication of stingless bee colonies without loss in viability of the perennial wild colony
Framework For a Collective Definition of Regenerative Agriculture in India
The concept of regenerative agriculture has received increasing attention worldwide as a method to restore and conserve natural resources while maintaining crop productivity. However, there remains a lack of consensus as to what conditions define regenerative agriculture, making it difficult for decision-makers, researchers, the agricultural sector, and the public to adopt regenerative agriculture practices. Here, we present the initial process to create a unified, cross-sectoral definition for regenerative agriculture in India that considers the viewpoints of multiple stakeholders and addresses the current challenges faced by the Indian agricultural sector. To this end, we compiled interactions with individuals from across India to identify the most pressing concerns for India's human and environmental ecosystems. We conducted over 30 hours of workshops to discuss these concerns with 50 experts from five sectors and four countries
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Not AvailableRed palm weevil, Rhynchophorus ferrugineus (Olivier),is a destructive pest of palms across the globe. Concealed nature of the pest is a hurdle in its management. Pheromone traps are a vital component in integrated management of the pest. Previous experiences reveal that use of pheromone, in isolation, trapped lower number of weevils as compared to their use in tandem with food baits. Attempts were made to study physiological and behavioral response of RPWto food baits viz.,banana, pineapple and coconut petiole. Electrophysiological responses revealed that head space volatiles trapped from banana elicited the highest EAG response of 0.7 mVfollowed by pineapple (0.65 mV) and coconut petiole (0.2 mV). Behaviourally, orientation of adult weevils to banana, pineapple and coconut petiole volatiles ranged from 70 to 75 per cent. In field assay, banana volatiles compounds with aggregation pheromone attracted a higher mean number of adult weevils of 55.3, followed by 51.7 with pineapple and 40.6 with coconut petiole volatiles.Not Availabl
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Not AvailableSurvival and infectivity of entomopathogenic nematodes (EPNs), Steinernema carpocapsae and Heterorhabditis indica were studied after passing the nematodes through the earthworm's, Eudrilus eugeniae gut. Infectivity was evaluated against first instar grubs of rhinoceros beetle, Oryctes rhinoceros. Both the species of EPNs had no deleterious effects on earthworms. S. carpocapsae and H.indica were recovered from the casts of earthworms. Infective juveniles (IJs) of both the EPNs species were successfully transmitted by young and adults of E. eugeniae. More than 50% of IJs recovered from the earthworm casts were viable and pathogenic to first instar grubs of O. rhinoceros. Although entomopathogenic nematodes had no deleterious effects on earthworms, their passage through E. eugeniae gut affected their mobility but not their virulence. Combined application of earthworms with entomopathogenic nematodes may enhance levels of inundative or inoculative biocontrol.Not Availabl
Electrophysiological responses of chafer beetle, Holotrichia serrata (F.) (Coleoptera: Scarabaeidae)
The chafer beetle, Holotrichia serrata F. (Coleoptera: Scarabaeidae) in its larval stage is a serious pest on sugarcane, vegetables, groundnut and coconut in many parts of India. The antennal response of adults to host volatiles and pheromone gland extracts was assessed by electroantennography. Among the preferred host of H. serrata, the volatiles from neem, Azadirachta indica A. Juss leaf extract elicited higher antennal response than gulmohar Delonix regia L. flowers and Ailanthus excelsa (Roxb) leaf extracts. The order of response was the same irrespective of the sex. In general the antennal response to pheromone gland and host extracts was higher in males than in females