New protocol for colchicine induced efficient doubled haploidy in haploid regenerants of tetraploid and hexaploid wheats at In vitro level

An investigation to standardize the protocol for in vitro application of colchicine for enhancing the doubled haploid production in wheat was done. Two tetraploid (PDW-314 and A-9-30-1); and two hexaploid (DH-40 and C-306) wheat genotypes were used as maternal parents, whereas, the pollen sources involved Zea mays (cv. Bajaura Makka) and Imperata cylindrica. During the rabi seasons of years 2013–14 and 2014–15, wheat × maize and wheat × I. cylindrica hybridization was carried out followed by treatment of their haploids produced as a result of elimination of chromosomes of maize and I. cylindrica respectively, with varied doses of colchicine for different durations The various doses of colchicine were categorized into two groups: lower doses for longer durations (0.01, 0.025, 0.05% each for 5, 7, 9, 11 hrs) and higher doses for shorter durations (0.05, 0.075, 0.10, 0.15, 0.20, 0.25% each for 5, 4, 3, 2 hrs). The response of different concentrations of colchicine applied for varied durations revealed significant differences for various doubled haploidy parameters viz., per cent survived plants, per cent doubled haploid formation and per cent doubled haploid seed formation. In hexaploid and tetraploid wheats, colchicine doses of 0.075% for 4 hrs and 0.15% for 4 hrs, respectively were established as optimum for enhanced doubled haploid production

Bioprospecting and molecular characterization of laccase producing bacteriafrom industrial contaminated sites

Laccases have vast prospective for biotechnological applications due to their outstanding bioremediation potential. These include abundant applications in effluent detoxification, enzymatic conversion of chemical intermediates, wine clarification degradation of textile dyes etc. In the present study, two potential microbes were isolated on solid medium containing guaiacol and ABTS for laccase activity out of 10 microbes. Two cultures PHP7 and PKD5 were selected for molecular characterization was carried out using 16S rRNA gene technology of PHP7 revealed as Bacillus cereus (KU878970.1).Partial amplification of laccase gene contain conserved domain of multicopper oxidase family. The biomass produced by PHP7 was 0.053 mg/5 mL, while PKD5 was 0.058 mg/5 mL. While dye degradation of PHP7dye of 64.28% after incubation of 6 days at pH7 whereas  PKD5 shows highest degradation of dye i.e. 61.90% after incubation of 8 days at pH8. PHP7 showed highest Laccase activity of 0.489 U/L at pH 7 while PKD5 showed 0.404 U/L Laccase activity at pH 8 at 8th day of incubation. Using laccase from PHP7 and PKD5 isolates, explored at industrial level for decolorization of coloured effluents that significance in  environmentally friendly and play critical role as bioremediation at commercial scale

Haploid Induction in Triticale × Wheat and Wheat × Rye Derivatives Following Imperata cylindrica-Mediated Chromosome Elimination Approach

The present research endeavor was undertaken to depict the response of different generations viz., F1, F2, BC1F1, BC1F2, BC1F3, BC1F4 and BC1F5 of triticale × wheat and wheat × rye hybrids towards the different parameters of haploid induction. The experimental material included the different generations obtained utilizing five genotypes of triticale (DT-123, DT-126, TL-2900, TL-2908 and TL-9335), four genotypes of Himalayan rye (Karoki rye, shanoor rye, tino rye and triloki rye) with various elite bread wheat genotypes as parents in wide hybridization programme. The triticale × wheat and wheat × rye recombinants were further subjected to Imperata cylindrica-mediated chromosome elimination approach of doubled haploidy breeding. The variability in the haploid induction parameters was observed to be under genetic control for embryo formation and regeneration, while pseudoseed formation was only affected by auxin treatment. Among the different generations, the backcross generations viz., BC1F1 and BC1F2 were found to exhibit significant positive response towards haploid induction parameters in both triticale × wheat and wheat × rye hybridization. Knowledge of effective generation for haploid induction in triticale × wheat and wheat × rye hybridization not only saved the time and energy but also enhanced the efficiency of haploid induction

Seed coat mediated resistance against Aspergillus flavus infection in peanut

Toxic metabolites known as aflatoxins are produced via certain species of the Aspergillus genus, specifically A. flavus, A. parasiticus, A. nomius, and A. tamarie. Although various pre- and post-harvest strategies have been employed, aflatoxin contamination remains a major problem within peanut crop, especially in subtropical environments. Aflatoxins are the most well-known and researched mycotoxins produced within the Aspergillus genus (namely Aspergillus flavus) and are classified as group 1 carcinogens. Their effects and etiology have been extensively researched and aflatoxins are commonly linked to growth defects and liver diseases in humans and livestock. Despite the known importance of seed coats in plant defense against pathogens, peanut seed coat mediated defenses against Aspergillus flavus resistance, have not received considerable attention. The peanut seed coat (testa) is primarily composed of a complex cell wall matrix consisting of cellulose, lignin, hemicellulose, phenolic compounds, and structural proteins. Due to cell wall desiccation during seed coat maturation, postharvest A. flavus infection occurs without the pathogen encountering any active genetic resistance from the live cell(s) and the testa acts as a physical and biochemical barrier only against infection. The structure of peanut seed coat cell walls and the presence of polyphenolic compounds have been reported to inhibit the growth of A. flavus and aflatoxin contamination; however, there is no comprehensive information available on peanut seed coat mediated resistance. We have recently reviewed various plant breeding, genomic, and molecular mechanisms, and management practices for reducing A. flavus infection and aflatoxin contamination. Further, we have also proved that seed coat acts as a physical and biochemical barrier against A. flavus infection. The current review focuses specifically on the peanut seed coat cell wall-mediated disease resistance, which will enable researchers to understand the mechanism and design efficient strategies for seed coat cell wall-mediated resistance against A. flavus infection and aflatoxin contamination

Intrinsic efficiency limits in low-bandgap non-fullerene acceptor organic solar cells

In bulk heterojunction (BHJ) organic solar cells (OSCs) both the electron affinity (EA) and ionization energy (IE) offsets at the donor–acceptor interface should equally control exciton dissociation. Here, we demonstrate that in low-bandgap non-fullerene acceptor (NFA) BHJs ultrafast donor-to-acceptor energy transfer precedes hole transfer from the acceptor to the donor and thus renders the EA offset virtually unimportant. Moreover, sizeable bulk IE offsets of about 0.5 eV are needed for efficient charge transfer and high internal quantum efficiencies, since energy level bending at the donor–NFA interface caused by the acceptors’ quadrupole moments prevents efficient exciton-to-charge-transfer state conversion at low IE offsets. The same bending, however, is the origin of the barrier-less charge transfer state to free charge conversion. Our results provide a comprehensive picture of the photophysics of NFA-based blends, and show that sizeable bulk IE offsets are essential to design efficient BHJ OSCs based on low-bandgap NFAs

Remediation of salt-affected soil by the addition of organic matter: an investigation into improving glutinous rice productivity

Soil salinity may limit plant growth and development, and cause yield loss in crop species. This study aimed at remediating saline soil using organic matter (OM) treatment, before the cultivation of RD6 rice (Oryza sativa L. spp. indica). Physiological and morphological characters of rice plants, as well as crop yield, were evaluated from salt-affected soil with varying levels of salinity. The chlorophyll a and total chlorophyll pigments of rice plants grown in salt-affected soil (2% salt level) with the application of OM were maintained better than in plants grown without OM treatment. The degree of reduced photosynthetic pigments in rice plants was dependent on the level of salt contamination. Pigment content was positively related to maximum quantum yield of PSII (Fv/Fm) and quantum efficiency of PSII (ΦPSII), leading to reduced net photosynthetic rate (Pn) and reduced total grain weight (TGW). Photosynthetic abilities, including chlorophyll a and total chlorophyll pigments and ΦPSII, in rice plants grown with OM treatment were greater than in those cultivated in soil without the OM treatment, especially in high salt levels (1-2% salt). The remediation of salt-affected soil in paddy fields using OM should be applied further, as an effective way of enhancing food crop productivity

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe