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Host searching behavior and potential of an aquatic ichneumonid pupal parasitoid of rice caseworm (Parapoynx stagnalis) in an upland rice paddy agro-ecosystem of the Western Ghats, India
No full textParapoynx stagnalis (Zeller) (Nymphula depunctalis (Guene´e)) is a sporadic rice paddy pest of south and southeast Asian rice paddy fields, and widely known as rice caseworm. A recent outbreak of the pest was observed in the upland rice paddy agro-ecosystem of the central
Western Ghats, India. No potential natural enemies of this pest have so far been reported, mainly due to the semi-aquatic behavior of the larvae and pupae. However, an undescribed aquatic ichneumonid wasp species (belonging to a genus near Litochila) is reported as a
potentially useful early stage pupal parasitoid of this pest in our study. The host searching behavior and potential of the parasitoid wasp was studied in detail using both field and laboratory experiments. The adult female wasps usually dive into the water in search of the host pupae, remaining under water for a maximum of 90.2 s, while searching for rice caseworm pupae. In field and laboratory experiments, we found 73% of the parasitized pupae of P. stagnalis kept under water yielded adult parasitic wasps. However, no parasitoids emerged from
parasitized host pupae maintained in dry terrariums. Sex ratio was 2.8:1. The present discovery of the semi aquatic parasitoid wasp could aid in better management of the rice caseworm population in rice paddy fields
Cross-Species Amplification of Coconut Microsatellite Markers in Rattans
No full textCross-species amplification of microsatellite loci is
considered to be a time-saving as well as a cost effective approach for developing locus specific markers for new species. In an attempt to identify molecular markers to determine gene flow events and genetic differentiation of populations in rattans, microsatellite primer pairs developed for Cocos nucifera (Arecaceae) were examined for cross-species amplification in rattans. Of the six microsatellite primer pairs screened, two (CNZ34 and CN2A5) yielded good cross-species amplification across different rattan genera and species from South and Southeast Asia. Based on microsatellite-specific PCR amplification products, cluster analysis was performed. The dendrogram indicated a clear grouping of rattans based on their genera and species. The coconut locus specific primer pairs could be successfully used to construct molecular differentiation of rattan genera across different geographical locations
DNA barcoding: An exercise in futility or utility?
No full textTaxonomy, the science of naming and classifying organisms, is the foundation of all biology. Unfortunately, over the past few decades, taxonomy is being completely overshadowed by seemingly spectacular
and glamorous branches of biology.However, in the last few years some of these subjects such as molecular biology have rejuvenated taxonomy as a fashionable
science once again. The advent of powerful DNA-based marker systems for identifying species has brought back the charm of 18th century biology and promises a less painstaking path for identification and discovery of new species on the ‘PCR-desk’ by ‘lay-taxonomists’ who
need not necessarily be ‘naturalists’.DNA barcoding, a tool that obtains species specific DNA signature, is based on the simple premise that sequence diversity within small stretches of the organism’s genome can provide a ‘biological barcode’ to enable identification of any organism at the species level1,2. As a result,scientists are hoping that DNA barcoding will provide a ‘universal key’ that will allow identification of a species by running unknown DNA sequences through a DNA barcode database
Pollination biology of large cardamom (Amomum subulatum)
Get PDFAmomum subulatum Roxb. (family Zingiberaceae) is
the large cardamom of commerce cultivated in tropical
wet evergreen forests of the Eastern Himalayas of
India, Nepal and Bhutan. This study seeks to identify
floral visitors and pollinators, examine floral adaptations for pollination and evaluate pollination efficiency. Studies were carried out in two flowering seasons (2005, 2006) in a 6-ha plantation located adjacent to a degraded reserve forest in the Sikkim part of the Himalayas. Only two flower visitor species, a bumble-bee (Bombus haemorrhoidalis Smith) and a honey bee species (Apis cerana F.) were recorded. The bumble-bee
was the effective and only pollinator, but A. ceranawas the pollen robber. Major flower adaptations for pollination by the bumble-bee are the length of the
nectar tube, which is not accessible to short-tongued
bees and a narrow passage in the fresh flower between
the anther–stigma column and the labellum. The narrow
passage forces the bumble-bee to push the anther–stigma column to enter the flower, which brings the body of the bumble-bee in contact with the anther and the stigma, and effects pollination. A. cerana does not come in contact with the stigma during pollen foraging and hence is unable to bring about pollination. Thus, structural features of the flower of A. subulatum differentiate the pollinator and the pollen robber. Pollination efficiency in the plantation was low due to the low population density of wild native pollinator, B. haemorrhoidalis
Biological Diversity Act, 2002: Shadow of permit-raj over research
Get PDFIt is too late in history of the world to think that there is time to produce ordered classifications of all plants, animals, fungi and micro-organisms, and then to employ
these classifications to seek new kinds of generalities while these organisms are still extant.
–Peter Rave
Insights on linking forests, trees, and people from the air, on the ground, and in the laboratory
No full textGoverning natural resources sustainably is a continuing struggle. Major debates occur over what types of policy “interventions” best protect forests, with choices of property and land tenure systems being central issues. Herein, we provide an overview of findings from a long-term interdisciplinary, multiscale, international research program that analyzes the institutional factors affecting forests managed under a variety of tenure arrangements. This program analyzes satellite images, conducts social-ecological measurements on the ground, and tests the impact of structural variables on human decisions in experimental laboratories. Satellite images track the landscape dimensions of forest-cover change within different management regimes over time. On-the-ground social-ecological studies examine relationships between forest conditions and types of institutions. Behavioral studies under controlled laboratory conditions enhance our understanding of explicit changes in structure that affect relevant human decisions. Evidence from all three research methods challenges the presumption that a single governance arrangement will control overharvesting in all settings. When users are genuinely engaged in decisions regarding rules affecting their use, the likelihood of them following the rules and monitoring others is much greater than when an authority simply imposes rules. Our results support a frontier of research on the most effective institutional and tenure arrangements for protecting forests. They move the debate beyond the boundaries of protected areas into larger landscapes where government, community, and comanaged protected areas are embedded and help us understand when and why deforestation and regrowth occur in specific regions within these larger landscapes
Biodiversity in Agricultural Landscapes: Saving Natural Capital without Losing Interest
No full textWhile species extinctions continue to be a matter of extreme concern, changes in biodiversity in the world's agricultural landscapes have largely escaped attention. Implicitly, the world community has traded off biodiversity in these landscapes against the conservation of threatened endemics in protected areas. But biodiversity loss in agricultural landscapes also has an opportunity cost. It affects not just the production of food, fuels, and fibers, but also a range of ecological services supporting, for example, water supplies, habitat, and health. Although increasing attention is being paid to the environmental context of modern agriculture, its role in biodiversity conservation has been largely ignored
Introduction to the special issue: Are parks working? Exploring human–environment tradeoffs in protected area conservation
No full textProtected areas, or parks, remain a major focus for biodiversity conservation globally. The goal of this special issue is to bring together a broad-based set of papers that examine the human dimensions of forest conservation in protected areas across the world. Park
landscapes are often characterized by biological and socio-political dilemmas due to conflicts between biodiversity goals and local livelihood strategies. To best inform policy, research should seek to document the livelihoods of people in the landscapes around parks
and investigate the impacts that parks and biodiversity outside the parks have on their livelihoods and activities in turn. Given the current debate on the effectiveness of protected area management, there is an urgent need for careful, quantitative evaluations that analyze the impact of exclusionary policies of protected area management on forest cover over time. Each of the four papers in this issue deals with a distinct case study, using different methods and questions. This research illustrates the utility of remote sensing, spatial statistics, fragmentation analyses and modeling for the study of parks, and for evaluation of the potential effectiveness of different management strategies in protected areas. These studies also underline the need for satellite image analysis to be supplemented by detailed field research to provide insights into the social and institutional processes that impact land cover change and forest conservation
People within parks—forest villages, land-cover change and landscape fragmentation in the Tadoba Andhari Tiger Reserve, India
No full textThere has been extensive debate on the conservation impact of people located within protected
areas. In a tiger reserve in central India, we find that the densely populated villages located outside
the park boundary are better connected to regional markets by road networks, and are associated
with greater deforestation rates and more forest fragmentation compared to the more isolated
villages in the park interior. The park itself however appears well protected in terms of forest cover
and connectivity. Instead of focusing on resettlement of forest villages, forest protection needs may
be better served by working with these surrounding communities to develop alternate mechanisms
for income generation
Feeding Fauna and Foraging Habits of Tiger Beetles Found in Agro-ecosystems in Western Ghats, ndia
No full textCicindela (Calochroa) whithilli (Hope) and Cicindela (Calochroa) flavomaculata Hope (Cicindelidae: Coleoptera) are seasonally dominant predatory insects in the cultivated, and irrigated rice paddy fields of the South Indian peninsula. While studying the feeding ecology of these tiger beetles in rice paddy agro-ecosystems in
Sringeri area of the central Western Ghats, we examined their potential as biocontrols on the major rice paddy pest populations available in this region. Earthworms
and tadpoles were significant prey organisms during the early cultivation period, while other traditional prey organisms like ants and spiders (mainly wolf and jumping
spiders) were more common as prey organisms toward the mid-season. The results showed that the feeding fauna of tiger beetles can extend to prey items beyond arthropods, to include vertebrates. Cicindela (Calochroa) duponti Dejean is another common species that occurs abundantly in the Areca orchards and on the bunds that separate rice paddy fields from adjacent uncultivated lands.We performed laboratory tests to determine the feeding guild of these beetles, and to investigate their possible role as a predator of the rice paddy pests. Although preliminary in nature, the results suggest that both C. whithilli and C. flavomaculata are ineffective as biocontrol agents of rice paddy agro-ecosystems. They appear to have only a marginal impact on the larvae of Leptocorisa acuta, a major insect pest of paddy rice, but
further experimental and observational studies are needed to firmly establish the significance of this observation