Native Philippine Heterorhabditis indica isolates from banana and rice fields and preliminary results of their virulence against the larvae of super worm (Zophobas morio Fabricius Coleoptera: Tenebrionidae)

Background: Entomopathogenic nematodes (EPNs) of the families Heterorhabditidae and Steinernematidae are used as biological control agents of several insect pests in lieu of synthetic pesticides. Results: Using an insect-baiting technique, naturally occurring EPN isolates were collected from banana and rice fields in the municipality of Hagonoy, the Philippines. A total of 4 isolates were recovered from all the sites namely, HBP1, HBP2, HR3 and HR4. By combining morphometrical and ITS rDNA data, all the isolates were identified as Heterorhabditis indica. To initially assess their infectivity, virulence tests were conducted on the last instar larvae of the super worm, Zophobas morio Fabricius (Coleoptera: Tenebrionidae), the model insect. HR3 isolate had the highest percentage mortality (56%), followed by HBP1 and HBP2 (33%), which were comparable to the available nematode in the market, Heterorhabditis bacteriophora (44%), whereas the lowest was obtained in HR4 isolate (11%). Conclusions: This study accounted 4 more H. indica isolates in addition to pre-existing isolates in the country, expanding its habitat range and geographic distribution. This also provides baseline information on the potential biocontrol utilization of native EPNs against soil-dwelling insect pests of agricultural crops. Further investigations are required to assess their efficacy against several other insect pests of economic importance for the integrated pest management (IPM) programmes in the country

Entomopathogenic Nematodes: Their Characterization, Bio-Control Properties and New Perspectives

The insect parasitoid nematodes are a means boon to agronomy and serve as important bio-pesticides for controlling crop damaging insect pests. These nematodes inhabit moist soils and have been to exist in all the continents excluding Polar Regions. These nematodes have 3rd larval stage infective which is the only free living stage existing outside the host. These infective stages are mutually associated with bacteria which reside in their alimentary canal and duo are responsible for mortality of the insect host. These nematodes are currently given great attention by scientific community because of their insect killing properties and can be used to replace hazardous pesticides. These nematodes include various species belonging to genus Heterorhabditis and Steinernema, and members of insectivorous group of genus Oscheius. Before their use as bio-control agents, these nematodes need to be properly identified. Currently, these nematodes are characterized by using morphological and morphometrical parameters and advanced molecular tools including cross hybridization and scanning electron microscope studies. Their associated bacterial partners are studied through advanced molecular and biochemical techniques. The properly characterized nematodes having more entomopathogenic properties can be easily mass produced through in vitro and in vivo methods. They can be formulated in various carrier materials and supplied to farmers for effective control of damaging insect pests. Several countries have formulated various useful products of entomopathogenic nematodes which are available in markets for use by the farmer community and some have given very effective results. India is still at the early stage in the use of these nematodes for bio-control of insects in agronomy. More research in this field needs to be carried, especially in India to produce effective indigenous nematode products which may prove a boon for agriculture

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum